4.3.1

* When using C++11, we could violate the one definition rule

* fix

* simplifying

* disabling new 'test' when using shared libs

.github/pull_request_template.md

@@ -6,6 +6,7 @@ Description
 
 Type of change
 - [ ] Bug fix
+- [ ] Optimization
 - [ ] New feature
 - [ ] Refactor / cleanup
 - [ ] Documentation / tests

.github/workflows/rvv-1024-clang-18.yml

@@ -19,11 +19,11 @@ jobs:
         sudo apt-get install -y cmake make g++-riscv64-linux-gnu qemu-user-static clang-18
     - name: Build
       run: |
-        CXX=clang++-18 CXXFLAGS="--target=riscv64-linux-gnu -march=rv64gcv_zvbb" \
-        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DCMAKE_BUILD_TYPE=Release -B build
-        cmake --build build/ -j$(nproc)
+        CC=clang-18 CXX=clang++-18 CFLAGS="--target=riscv64-linux-gnu -march=rv64gcv_zvbb" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build
+        cmake --build build/ -j$(nproc) --config Release
     - name: Test VLEN=1024
       run: |
-        export QEMU_LD_PREFIX="/usr/riscv64-linux-gnu"
-        export QEMU_CPU="rv64,v=on,zvbb=on,vlen=1024,rvv_ta_all_1s=on,rvv_ma_all_1s=on"
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,zvbb=on,vlen=1024,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
         ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)

.github/workflows/rvv-128-clang-17.yml

@@ -19,11 +19,6 @@ jobs:
         sudo apt-get install -y cmake make g++-riscv64-linux-gnu qemu-user-static clang-17
     - name: Build
       run: |
-        CXX=clang++-17 CXXFLAGS="--target=riscv64-linux-gnu -march=rv64gcv" \
-        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DCMAKE_BUILD_TYPE=Release -B build
-        cmake --build build/ -j$(nproc)
-    - name: Test VLEN=128
-      run: |
-        export QEMU_LD_PREFIX="/usr/riscv64-linux-gnu"
-        export QEMU_CPU="rv64,v=on,vlen=128,rvv_ta_all_1s=on,rvv_ma_all_1s=on"
-        ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)
+        CC=clang-17 CXX=clang++-17 CFLAGS="--target=riscv64-linux-gnu -march=rv64gcv" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build
+        cmake --build build/ -j$(nproc) --config Release

.github/workflows/rvv-128-clang-20.yml

@@ -0,0 +1,39 @@
+name: Ubuntu rvv VLEN=128 (clang 20)
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install packages
+      run: |
+        sudo apt-get update -q -y
+        sudo apt-get install -y cmake make g++-riscv64-linux-gnu qemu-user-static clang-20
+    - name: Build
+      run: |
+        CC=clang-20 CXX=clang++-20 CFLAGS="--target=riscv64-linux-gnu -march=rv64gcv" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build
+        cmake --build build/ -j$(nproc) --config Release
+    - name: Test VLEN=128
+      run: |
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,vlen=128,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
+        ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)
+    - name: Build VLS
+      run: |
+        CC=clang-20 CXX=clang++-20 CFLAGS="--target=riscv64-linux-gnu -march=rv64gcv_zvl128b_zba_zbb_zbc -mrvv-vector-bits=zvl" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build-vls
+        cmake --build build-vls/ -j$(nproc) --config Release
+    - name: Test VLEN=128 VLS
+      run: |
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,zba=on,zbb=on,zbc=on,vlen=128,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
+        ctest --timeout 1800 --output-on-failure --test-dir build-vls -j $(nproc)

.github/workflows/rvv-256-gcc-14.yml

@@ -19,11 +19,21 @@ jobs:
         sudo apt-get install -y cmake make g++-14-riscv64-linux-gnu qemu-user-static
     - name: Build
       run: |
-        CXX=riscv64-linux-gnu-g++-14 CXXFLAGS=-march=rv64gcv \
-        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DCMAKE_BUILD_TYPE=Release -B build
-        cmake --build build/ -j$(nproc)
+        CC=riscv64-linux-gnu-gcc-14 CXX=riscv64-linux-gnu-g++-14 CFLAGS=-march=rv64gcv CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build
+        cmake --build build/ -j$(nproc) --config Release
     - name: Test VLEN=256
       run: |
-        export QEMU_LD_PREFIX="/usr/riscv64-linux-gnu"
-        export QEMU_CPU="rv64,v=on,zvbb=on,vlen=256,rvv_ta_all_1s=on,rvv_ma_all_1s=on"
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,zvbb=on,vlen=256,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
         ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)
+    - name: Build VLS
+      run: |
+        CC=riscv64-linux-gnu-gcc-14 CXX=riscv64-linux-gnu-g++-14 CFLAGS="-march=rv64gcv_zvl256b -mrvv-vector-bits=zvl" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build-vls
+        cmake --build build-vls/ -j$(nproc) --config Release
+    - name: Test VLEN=256 VLS
+      run: |
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,zvbb=on,vlen=256,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
+        ctest --timeout 1800 --output-on-failure --test-dir build-vls -j $(nproc)

.github/workflows/rvv-512-clang-19.yml

@@ -0,0 +1,39 @@
+name: Ubuntu rvv VLEN=512 (clang 19)
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install packages
+      run: |
+        sudo apt-get update -q -y
+        sudo apt-get install -y cmake make g++-riscv64-linux-gnu qemu-user-static clang-19
+    - name: Build
+      run: |
+        CC=clang-19 CXX=clang++-19 CFLAGS="--target=riscv64-linux-gnu -march=rv64gcv" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build
+        cmake --build build/ -j$(nproc) --config Release
+    - name: Test VLEN=512
+      run: |
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,vlen=512,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
+        ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)
+    - name: Build VLS
+      run: |
+        CC=clang-19 CXX=clang++-19 CFLAGS="--target=riscv64-linux-gnu -march=rv64gcv_zvl512b_zba_zbb_zbc -mrvv-vector-bits=zvl" CXXFLAGS="${CFLAGS}" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DSIMDJSON_DEVELOPER_MODE=ON -B build-vls
+        cmake --build build-vls/ -j$(nproc) --config Release
+    - name: Test VLEN=512 VLS
+      run: |
+        QEMU_LD_PREFIX="/usr/riscv64-linux-gnu" \
+        QEMU_CPU="rv64,v=on,zba=on,zbb=on,zbc=on,vlen=512,rvv_ta_all_1s=on,rvv_ma_all_1s=on" \
+        ctest --timeout 1800 --output-on-failure --test-dir build-vls -j $(nproc)

CMakeLists.txt

@@ -1,9 +1,18 @@
 cmake_minimum_required(VERSION 3.14)
 
+# Build performance optimizations
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON CACHE BOOL "Export compile commands for faster IDE integration")
+set_property(GLOBAL PROPERTY USE_FOLDERS ON)
+
+# Enable parallel compilation on MSVC
+if(MSVC)
+  add_compile_options(/MP)
+endif()
+
 project(
     simdjson
     # The version number is modified by tools/release.py
-    VERSION 4.2.4
+    VERSION 4.3.1
     DESCRIPTION "Parsing gigabytes of JSON per second"
     HOMEPAGE_URL "https://simdjson.org/"
     LANGUAGES CXX C
@@ -20,8 +29,8 @@ string(
 # ---- Options, variables ----
 
 # These version numbers are modified by tools/release.py
-set(SIMDJSON_LIB_VERSION "29.0.0" CACHE STRING "simdjson library version")
-set(SIMDJSON_LIB_SOVERSION "29" CACHE STRING "simdjson library soversion")
+set(SIMDJSON_LIB_VERSION "30.0.0" CACHE STRING "simdjson library version")
+set(SIMDJSON_LIB_SOVERSION "30" CACHE STRING "simdjson library soversion")
 
 option(SIMDJSON_BUILD_STATIC_LIB "Build simdjson_static library along with simdjson (only makes sense if BUILD_SHARED_LIBS=ON)" OFF)
 if(SIMDJSON_BUILD_STATIC_LIB AND NOT BUILD_SHARED_LIBS)
@@ -83,10 +92,36 @@ add_library(simdjson ${SIMDJSON_SOURCES})
 add_library(simdjson::simdjson ALIAS simdjson)
 set(SIMDJSON_LIBRARIES simdjson)
 
+# Enable precompiled headers for faster builds
+if(CMAKE_VERSION VERSION_GREATER_EQUAL "3.16")
+  target_precompile_headers(simdjson PRIVATE
+    <algorithm>
+    <array>
+    <atomic>
+    <bit>
+    <cassert>
+    <cctype>
+    <cerrno>
+    <cstddef>
+    <cstdint>
+    <cstdlib>
+    <cstring>
+    <memory>
+    <string>
+    <utility>
+    <vector>
+  )
+endif()
+
 if(SIMDJSON_BUILD_STATIC_LIB)
   add_library(simdjson_static STATIC ${SIMDJSON_SOURCES})
   add_library(simdjson::simdjson_static ALIAS simdjson_static)
   list(APPEND SIMDJSON_LIBRARIES simdjson_static)
+
+  # Reuse precompiled headers for static library
+  if(CMAKE_VERSION VERSION_GREATER_EQUAL "3.16")
+    target_precompile_headers(simdjson_static REUSE_FROM simdjson)
+  endif()
 endif()
 
 set_target_properties(
@@ -112,6 +147,14 @@ simdjson_add_props(
     PRIVATE "$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src>"
 )
 
+# Optimize linker settings for faster builds
+if(MSVC)
+  target_link_options(simdjson PRIVATE /INCREMENTAL)
+  if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+    target_link_options(simdjson PRIVATE /DEBUG:FASTLINK)
+  endif()
+endif()
+
 if(SIMDJSON_STATIC_REFLECTION)
   # We would like to require C++26, but no compiler supports that!
   # This is a hack:
@@ -140,24 +183,6 @@ if(SIMDJSON_MINUS_ZERO_AS_FLOAT)
   simdjson_add_props(target_compile_definitions PRIVATE SIMDJSON_MINUS_ZERO_AS_FLOAT=1)
 endif(SIMDJSON_MINUS_ZERO_AS_FLOAT)
 
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^(loongarch64)$")
-    option(SIMDJSON_PREFER_LSX "Prefer LoongArch SX" ON)
-    include(CheckCXXCompilerFlag)
-    check_cxx_compiler_flag(-mlasx COMPILER_SUPPORTS_LASX)
-    check_cxx_compiler_flag(-mlsx COMPILER_SUPPORTS_LSX)
-    if(COMPILER_SUPPORTS_LASX AND NOT SIMDJSON_PREFER_LSX)
-        simdjson_add_props(
-            target_compile_options PRIVATE
-            -mlasx
-        )
-    elseif(COMPILER_SUPPORTS_LSX)
-        simdjson_add_props(
-            target_compile_options PRIVATE
-            -mlsx
-        )
-    endif()
-endif()
-
 # GCC and Clang have horrendous Debug builds when using SIMD.
 # A common fix is to use '-Og' instead.
 # bug https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54412
@@ -171,7 +196,12 @@ if(
       target_compile_options PRIVATE
       $<$<CONFIG:DEBUG>:-Og>
   )
-endif()
+  # We still want to enable development checks in Debug mode
+  simdjson_add_props(
+      target_compile_definitions PUBLIC
+      SIMDJSON_DEVELOPMENT_CHECKS
+  )
+  endif()
 
 if(SIMDJSON_ENABLE_THREADS)
   find_package(Threads REQUIRED)

Doxyfile

@@ -38,7 +38,7 @@ PROJECT_NAME           = simdjson
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = "4.2.4"
+PROJECT_NUMBER         = "4.3.1"
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a

HACKING.md

@@ -110,6 +110,24 @@ workflows used by simdjson.
 Directory Structure and Source
 ------------------------------
 
+Before diving into the directory structure, here are key concepts used in the codebase:
+
+- **Amalgamated File**: A file that is conditionally included in the amalgamation process. These are wrapped in `#ifndef SIMDJSON_CONDITIONAL_INCLUDE` blocks and are included based on the target implementation (e.g., ARM64, x86). They include implementation-specific files (e.g., `arm64.h`) and generic files (e.g., under `generic/`). Amalgamated files have associated dependency files (`dependencies.h`) to track includes.
+
+- **Amalgamator File**: A file that orchestrates the inclusion of amalgamated files. Examples: `arm64.h`, `arm64/implementation.h`, `generic/amalgamated.h`. These are not themselves amalgamated but control conditional inclusions.
+
+- **Free Dependency File**: A top-level header that is always included unconditionally. These do not have dependency files and represent the public API (e.g., main headers).
+
+- **Implementation-Specific File**: A file tied to a specific CPU architecture or instruction set (e.g., `arm64/`, `haswell/`). These must be amalgamated.
+
+- **Generic File**: A shared file (under `generic/` or `simdjson/generic/`) that contains common code included once per implementation.
+
+- **Builtin File**: Special files under `simdjson/builtin/` that handle the builtin implementation, a fallback/default implementation used when no optimized implementation is available.
+
+- **Conditional Include Block**: A section wrapped in `#ifndef SIMDJSON_CONDITIONAL_INCLUDE` for editor-only or implementation-specific content.
+
+The script `singleheader/amalgation_helper.py` will generate an HTML report which you can use to visualize the status of each file.
+
 simdjson's source structure, from the top level, looks like this:
 
 * **CMakeLists.txt:** The main build system.
@@ -133,6 +151,12 @@ simdjson's source structure, from the top level, looks like this:
     * simdjson/generic/ondemand/*.h: individual On-Demand classes, generically written.
       * simdjson/generic/ondemand/dependencies.h: dependencies on common, non-implementation-specific simdjson classes. This will be included before including amalgamated.h.
       * simdjson/generic/ondemand/amalgamated.h: all generic ondemand classes for an implementation.
+  * simdjson/builder.h: the `simdjson::builder` namespace. Includes all public builder classes.
+    * simdjson/builtin/builder.h: the `simdjson::builtin::builder` namespace.
+    * simdjson/arm64|fallback|haswell|icelake|ppc64|westmere/builder.h: the `simdjson::<implementation>::builder` namespace. Builder compiled for the specific implementation.
+    * simdjson/generic/builder/*.h: individual Builder classes, generically written.
+      * simdjson/generic/builder/dependencies.h: dependencies on common, non-implementation-specific simdjson classes. This will be included before including amalgamated.h.
+      * simdjson/generic/builder/amalgamated.h: all generic builder classes for an implementation.
 * **src:** The source files for non-inlined functionality (e.g. the architecture-specific parser
   implementations).
   * simdjson.cpp: A "main source" that includes all implementation files from src/. This is
@@ -147,6 +171,7 @@ Other important files and directories:
 * **.github/workflows:** Definitions for GitHub Actions (CI).
 * **singleheader:** Contains generated `simdjson.h` and `simdjson.cpp` that we release. The files `singleheader/simdjson.h` and `singleheader/simdjson.cpp` should never be edited by hand.
 * **singleheader/amalgamate.py:** Generates `singleheader/simdjson.h` and `singleheader/simdjson.cpp` for release (python script). If you add a new implementation (e.g., rvv), you need to edit this file (IMPLEMENTATIONS).
+* **singleheader/amalgation_helper.py:** Generates and `amalgamation_report.html` that helps you understand the status of each file.
 * **benchmark:** This is where we do benchmarking. Benchmarking is core to every change we make; the
   cardinal rule is don't regress performance without knowing exactly why, and what you're trading
   for it. Many of our benchmarks are microbenchmarks. We are effectively doing controlled scientific experiments for the purpose of understanding what affects our performance. So we simplify as much as possible. We try to avoid irrelevant factors such as page faults, interrupts, unnecessary system calls. We recommend checking the performance as follows:

README.md

@@ -6,7 +6,8 @@
 simdjson : Parsing gigabytes of JSON per second
 ===============================================
 
-<img src="images/logo.png" width="10%" style="float: right">
+<img src="images/official_logo/logo_noir/SVG/logo_simdjson_noir.svg" width="40%" style="float: right">
+
 JSON is everywhere on the Internet. Servers spend a *lot* of time parsing it. We need a fresh
 approach. The simdjson library uses commonly available SIMD instructions and microparallel algorithms
 to parse JSON 4x  faster than RapidJSON and 25x faster than JSON for Modern C++.
@@ -63,6 +64,7 @@ Real-world usage
 - [RonDB](https://github.com/logicalclocks/rondb)
 - [GreptimeDB](https://github.com/GreptimeTeam/greptimedb)
 - [mamba](https://github.com/mamba-org/mamba)
+- [Ladybird Browser](https://ladybird.org)
 
 
 If you are planning to use simdjson in a product, please work from one of our releases.
@@ -212,6 +214,21 @@ For the video inclined, <br />
 [![simdjson at QCon San Francisco 2019](http://img.youtube.com/vi/wlvKAT7SZIQ/0.jpg)](http://www.youtube.com/watch?v=wlvKAT7SZIQ)<br />
 (It was the best voted talk, we're kinda proud of it.)
 
+Citing this work
+-----------------
+
+If you use simdjson in published research, please cite the software library. A suitable BibTeX entry is:
+
+```bibtex
+@misc{simdjson,
+  title={{The simdjson library: Parsing Gigabytes of JSON per Second}},
+  author={Daniel Lemire and Geoff Langdale and John Keiser and Paul Dreik and Francisco Thiesen and others},
+  year={2019},
+  howpublished={Software library},
+  note={https://github.com/simdjson/simdjson}
+}
+```
+
 Funding
 -------
 

benchmark/apple/apple_arm_events.h

@@ -245,7 +245,7 @@ static u32 (*kpc_get_counter_count)(u32 classes);
 
 /// Get counter accumulations.
 /// If `all_cpus` is true, the buffer count should not smaller than
-/// (cpu_count * counter_count). Otherwize, the buffer count should not smaller
+/// (cpu_count * counter_count). Otherwise, the buffer count should not smaller
 /// than (counter_count).
 /// @see kpc_get_counter_count(), kpc_cpu_count().
 /// @param all_cpus true for all CPUs, false for current cpu.
@@ -374,7 +374,7 @@ static int kperf_lightweight_pet_set(u32 enabled) {
 // These functions do not require root privileges.
 // -----------------------------------------------------------------------------
 
-// KPEP CPU archtecture constants.
+// KPEP CPU architecture constants.
 #define KPEP_ARCH_I386 0
 #define KPEP_ARCH_X86_64 1
 #define KPEP_ARCH_ARM 2
@@ -414,7 +414,7 @@ typedef struct kpep_db {
   usize fixed_counter_count;
   usize config_counter_count;
   usize power_counter_count;
-  u32 archtecture; ///< see `KPEP CPU archtecture constants` above.
+  u32 architecture; ///< see `KPEP CPU architecture constants` above.
   u32 fixed_counter_bits;
   u32 config_counter_bits;
   u32 power_counter_bits;

benchmark/static_reflect/CMakeLists.txt

@@ -8,7 +8,7 @@ CPMAddPackage(
 
 option(SIMDJSON_USE_RUST "Build the static_reflect benchmark" OFF)
 
-if(SIMDJSON_USER_RUST)
+if(SIMDJSON_USE_RUST)
   if(NOT WIN32)
   # We want the check whether Rust is available before trying to build a crate.
   CPMAddPackage(
@@ -39,9 +39,9 @@ if(SIMDJSON_USER_RUST)
       message(STATUS "curl https://sh.rustup.rs -sSf | sh")
     endif()
   endif()
-else(SIMDJSON_USER_RUST)
+else(SIMDJSON_USE_RUST)
   message(STATUS "We will not benchmark serde-benchmark." )
-endif(SIMDJSON_USER_RUST)
+endif(SIMDJSON_USE_RUST)
 
 # Add the benchmark executable targets
 add_subdirectory(twitter_benchmark)

benchmark/static_reflect/citm_catalog_benchmark/CMakeLists.txt

@@ -1,4 +1,5 @@
 add_executable(benchmark_serialization_citm_catalog benchmark_serialization_citm_catalog.cpp)
+add_executable(benchmark_parsing_citm benchmark_parsing_citm.cpp)
 
 # Link with Rust benchmarking code if available
 if(TARGET serde-benchmark)
@@ -11,4 +12,29 @@ target_link_libraries(benchmark_serialization_citm_catalog PRIVATE simdjson::sim
 target_link_libraries(benchmark_serialization_citm_catalog PRIVATE reflectcpp)
 target_compile_definitions(benchmark_serialization_citm_catalog PRIVATE SIMDJSON_BENCH_CPP_REFLECT=1)
 
-target_compile_definitions(benchmark_serialization_citm_catalog PRIVATE JSON_FILE="${BENCH_CITM_JSON}")
+if(TARGET yyjson)
+    target_link_libraries(benchmark_serialization_citm_catalog PRIVATE yyjson)
+    target_compile_definitions(benchmark_serialization_citm_catalog PRIVATE SIMDJSON_COMPETITION_YYJSON)
+endif()
+
+target_compile_definitions(benchmark_serialization_citm_catalog PRIVATE JSON_FILE="${BENCH_CITM_JSON}")
+
+# Configuration for parsing benchmark
+if(TARGET serde-benchmark)
+    target_link_libraries(benchmark_parsing_citm PRIVATE serde-benchmark)
+    target_compile_definitions(benchmark_parsing_citm PRIVATE SIMDJSON_RUST_VERSION="${Rust_VERSION}")
+endif()
+
+target_link_libraries(benchmark_parsing_citm PRIVATE simdjson::simdjson nlohmann_json)
+
+if(TARGET rapidjson)
+    target_link_libraries(benchmark_parsing_citm PRIVATE rapidjson)
+    target_compile_definitions(benchmark_parsing_citm PRIVATE SIMDJSON_COMPETITION_RAPIDJSON)
+endif()
+
+if(TARGET yyjson)
+    target_link_libraries(benchmark_parsing_citm PRIVATE yyjson)
+    target_compile_definitions(benchmark_parsing_citm PRIVATE SIMDJSON_COMPETITION_YYJSON)
+endif()
+
+target_compile_definitions(benchmark_parsing_citm PRIVATE JSON_FILE="${BENCH_CITM_JSON}")

benchmark/static_reflect/citm_catalog_benchmark/benchmark_parsing_citm.cpp

@@ -0,0 +1,563 @@
+#include <cassert>
+#include <cstdlib>
+#include <ctime>
+#include <format>
+#include <fstream>
+#include <iostream>
+#include <nlohmann/json.hpp>
+#include <simdjson.h>
+#include <string>
+#include "citm_catalog_data.h"
+#include "nlohmann_citm_catalog_data.h"
+#include "../benchmark_utils/benchmark_helper.h"
+
+#ifdef SIMDJSON_COMPETITION_RAPIDJSON
+#include "rapidjson_citm_catalog_data.h"
+#endif
+
+#ifdef SIMDJSON_COMPETITION_YYJSON
+#include "yyjson_citm_catalog_data.h"
+#endif
+
+#ifdef SIMDJSON_RUST_VERSION
+#include "../serde-benchmark/serde_benchmark.h"
+
+void bench_rust_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_rust_parsing",
+               bench([&json_str, &result]() {
+                 serde_benchmark::CitmCatalog *catalog = serde_benchmark::citm_from_str(json_str.c_str(), json_str.size());
+                 result = (catalog != nullptr);
+                 if (catalog) {
+                   serde_benchmark::free_citm(catalog);
+                 }
+                 if (!result) {
+                   printf("parse error\n");
+                 }
+               }));
+}
+#endif
+
+template <class T> void bench_simdjson_static_reflection_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  // Pre-allocate padded buffer outside the benchmark loop
+  std::string mutable_json = json_str;
+  simdjson::pad(mutable_json);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_simdjson_static_reflection_parsing",
+               bench([&mutable_json, &result]() {
+                 simdjson::ondemand::parser parser;
+                 simdjson::ondemand::document doc;
+                 if(parser.iterate(mutable_json).get(doc)) {
+                   result = false;
+                   return;
+                 }
+                 T my_struct;
+                 if(doc.get<T>().get(my_struct)) {
+                   result = false;
+                 }
+                 if (!result) {
+                   printf("parse error\n");
+                 }
+               }));
+}
+
+#if SIMDJSON_STATIC_REFLECTION
+template <class T> void bench_simdjson_from_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  // Pre-allocate padded buffer outside the benchmark loop
+  simdjson::padded_string padded = simdjson::padded_string(json_str);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_simdjson_from_parsing",
+               bench([&padded, &result]() {
+                 T my_struct;
+                 auto err = simdjson::from(padded).get(my_struct);
+                  if (err) {
+                    result = false;
+                    printf("parse error: %s\n", simdjson::error_message(err));
+                    return;
+                  }
+               }));
+}
+#endif
+
+// nlohmann::json deserialization functions
+void from_json(const nlohmann::json &j, CITMPrice &p) {
+    j.at("amount").get_to(p.amount);
+    j.at("audienceSubCategoryId").get_to(p.audienceSubCategoryId);
+    j.at("seatCategoryId").get_to(p.seatCategoryId);
+}
+
+void from_json(const nlohmann::json &j, CITMArea &a) {
+    j.at("areaId").get_to(a.areaId);
+    j.at("blockIds").get_to(a.blockIds);
+}
+
+void from_json(const nlohmann::json &j, CITMSeatCategory &s) {
+    j.at("areas").get_to(s.areas);
+    j.at("seatCategoryId").get_to(s.seatCategoryId);
+}
+
+void from_json(const nlohmann::json &j, CITMPerformance &p) {
+    j.at("id").get_to(p.id);
+    j.at("eventId").get_to(p.eventId);
+    if (j.contains("logo") && !j["logo"].is_null()) {
+        p.logo = j["logo"].get<std::string>();
+    }
+    if (j.contains("name") && !j["name"].is_null()) {
+        p.name = j["name"].get<std::string>();
+    }
+    j.at("prices").get_to(p.prices);
+    j.at("seatCategories").get_to(p.seatCategories);
+    if (j.contains("seatMapImage") && !j["seatMapImage"].is_null()) {
+        p.seatMapImage = j["seatMapImage"].get<std::string>();
+    }
+    j.at("start").get_to(p.start);
+    j.at("venueCode").get_to(p.venueCode);
+}
+
+void from_json(const nlohmann::json &j, CITMEvent &e) {
+    j.at("id").get_to(e.id);
+    j.at("name").get_to(e.name);
+    if (j.contains("description") && !j["description"].is_null()) {
+        e.description = j["description"].get<std::string>();
+    }
+    if (j.contains("logo") && !j["logo"].is_null()) {
+        e.logo = j["logo"].get<std::string>();
+    }
+    j.at("subTopicIds").get_to(e.subTopicIds);
+    if (j.contains("subjectCode") && !j["subjectCode"].is_null()) {
+        e.subjectCode = j["subjectCode"].get<std::string>();
+    }
+    if (j.contains("subtitle") && !j["subtitle"].is_null()) {
+        e.subtitle = j["subtitle"].get<std::string>();
+    }
+    j.at("topicIds").get_to(e.topicIds);
+}
+
+void from_json(const nlohmann::json &j, CitmCatalog &c) {
+    j.at("events").get_to(c.events);
+    j.at("performances").get_to(c.performances);
+}
+
+CitmCatalog nlohmann_deserialize(const std::string &json_str) {
+    nlohmann::json j = nlohmann::json::parse(json_str);
+    return j.get<CitmCatalog>();
+}
+
+void bench_nlohmann_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_nlohmann_parsing",
+               bench([&json_str, &result]() {
+                 try {
+                   CitmCatalog data = nlohmann_deserialize(json_str);
+                   result = true;
+                 } catch (...) {
+                   result = false;
+                   printf("parse error\n");
+                 }
+               }));
+}
+
+#ifdef SIMDJSON_COMPETITION_RAPIDJSON
+CitmCatalog rapidjson_deserialize(const std::string &json_str) {
+    rapidjson::Document doc;
+    doc.Parse(json_str.c_str());
+
+    if (doc.HasParseError()) {
+        throw std::runtime_error("RapidJSON parse error");
+    }
+
+    CitmCatalog catalog;
+
+    // Parse events
+    if (doc.HasMember("events") && doc["events"].IsObject()) {
+        for (auto& m : doc["events"].GetObject()) {
+            CITMEvent event;
+            const auto& e = m.value;
+
+            event.id = e["id"].GetUint64();
+            event.name = e["name"].GetString();
+            if (e.HasMember("description") && !e["description"].IsNull()) {
+                event.description = e["description"].GetString();
+            }
+            if (e.HasMember("logo") && !e["logo"].IsNull()) {
+                event.logo = e["logo"].GetString();
+            }
+
+            event.subTopicIds.clear();
+            for (auto& id : e["subTopicIds"].GetArray()) {
+                event.subTopicIds.push_back(id.GetUint64());
+            }
+
+            if (e.HasMember("subjectCode") && !e["subjectCode"].IsNull()) {
+                event.subjectCode = e["subjectCode"].GetString();
+            }
+            if (e.HasMember("subtitle") && !e["subtitle"].IsNull()) {
+                event.subtitle = e["subtitle"].GetString();
+            }
+
+            event.topicIds.clear();
+            for (auto& id : e["topicIds"].GetArray()) {
+                event.topicIds.push_back(id.GetUint64());
+            }
+
+            catalog.events[m.name.GetString()] = event;
+        }
+    }
+
+    // Parse performances
+    if (doc.HasMember("performances") && doc["performances"].IsArray()) {
+        for (auto& p : doc["performances"].GetArray()) {
+            CITMPerformance perf;
+
+            perf.id = p["id"].GetUint64();
+            perf.eventId = p["eventId"].GetUint64();
+            if (p.HasMember("logo") && !p["logo"].IsNull()) {
+                perf.logo = p["logo"].GetString();
+            }
+            if (p.HasMember("name") && !p["name"].IsNull()) {
+                perf.name = p["name"].GetString();
+            }
+
+            // Parse prices
+            for (auto& price : p["prices"].GetArray()) {
+                CITMPrice pr;
+                pr.amount = price["amount"].GetUint64();
+                pr.audienceSubCategoryId = price["audienceSubCategoryId"].GetUint64();
+                pr.seatCategoryId = price["seatCategoryId"].GetUint64();
+                perf.prices.push_back(pr);
+            }
+
+            // Parse seat categories
+            for (auto& sc : p["seatCategories"].GetArray()) {
+                CITMSeatCategory seatCat;
+                seatCat.seatCategoryId = sc["seatCategoryId"].GetUint64();
+
+                for (auto& area : sc["areas"].GetArray()) {
+                    CITMArea ar;
+                    ar.areaId = area["areaId"].GetUint64();
+                    for (auto& block : area["blockIds"].GetArray()) {
+                        ar.blockIds.push_back(block.GetUint64());
+                    }
+                    seatCat.areas.push_back(ar);
+                }
+                perf.seatCategories.push_back(seatCat);
+            }
+
+            if (p.HasMember("seatMapImage") && !p["seatMapImage"].IsNull()) {
+                perf.seatMapImage = p["seatMapImage"].GetString();
+            }
+            perf.start = p["start"].GetUint64();
+            perf.venueCode = p["venueCode"].GetString();
+
+            catalog.performances.push_back(perf);
+        }
+    }
+
+    return catalog;
+}
+
+void bench_rapidjson_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_rapidjson_parsing",
+               bench([&json_str, &result]() {
+                 try {
+                   CitmCatalog data = rapidjson_deserialize(json_str);
+                   result = true;
+                 } catch (...) {
+                   result = false;
+                   printf("parse error\n");
+                 }
+               }));
+}
+#endif
+
+#ifdef SIMDJSON_COMPETITION_YYJSON
+CitmCatalog yyjson_deserialize(const std::string &json_str) {
+    yyjson_doc *doc = yyjson_read(json_str.c_str(), json_str.size(), 0);
+    if (!doc) {
+        throw std::runtime_error("YYJson parse error");
+    }
+
+    yyjson_val *root = yyjson_doc_get_root(doc);
+    CitmCatalog catalog;
+
+    // Parse events
+    yyjson_val *events = yyjson_obj_get(root, "events");
+    if (events) {
+        size_t idx, max;
+        yyjson_val *key, *val;
+        yyjson_obj_foreach(events, idx, max, key, val) {
+            CITMEvent event;
+
+            event.id = yyjson_get_uint(yyjson_obj_get(val, "id"));
+            const char* name = yyjson_get_str(yyjson_obj_get(val, "name"));
+            if (name) event.name = name;
+
+            yyjson_val *desc = yyjson_obj_get(val, "description");
+            if (desc && !yyjson_is_null(desc)) {
+                const char* str = yyjson_get_str(desc);
+                if (str) event.description = str;
+            }
+
+            yyjson_val *logo = yyjson_obj_get(val, "logo");
+            if (logo && !yyjson_is_null(logo)) {
+                const char* str = yyjson_get_str(logo);
+                if (str) event.logo = str;
+            }
+
+            yyjson_val *subTopics = yyjson_obj_get(val, "subTopicIds");
+            if (subTopics) {
+                size_t sidx, smax;
+                yyjson_val *sval;
+                yyjson_arr_foreach(subTopics, sidx, smax, sval) {
+                    event.subTopicIds.push_back(yyjson_get_uint(sval));
+                }
+            }
+
+            yyjson_val *subjectCode = yyjson_obj_get(val, "subjectCode");
+            if (subjectCode && !yyjson_is_null(subjectCode)) {
+                const char* str = yyjson_get_str(subjectCode);
+                if (str) event.subjectCode = str;
+            }
+
+            yyjson_val *subtitle = yyjson_obj_get(val, "subtitle");
+            if (subtitle && !yyjson_is_null(subtitle)) {
+                const char* str = yyjson_get_str(subtitle);
+                if (str) event.subtitle = str;
+            }
+
+            yyjson_val *topics = yyjson_obj_get(val, "topicIds");
+            if (topics) {
+                size_t tidx, tmax;
+                yyjson_val *tval;
+                yyjson_arr_foreach(topics, tidx, tmax, tval) {
+                    event.topicIds.push_back(yyjson_get_uint(tval));
+                }
+            }
+
+            const char* keyStr = yyjson_get_str(key);
+            if (keyStr) {
+                catalog.events[keyStr] = event;
+            }
+        }
+    }
+
+    // Parse performances
+    yyjson_val *performances = yyjson_obj_get(root, "performances");
+    if (performances) {
+        size_t idx, max;
+        yyjson_val *val;
+        yyjson_arr_foreach(performances, idx, max, val) {
+            CITMPerformance perf;
+
+            perf.id = yyjson_get_uint(yyjson_obj_get(val, "id"));
+            perf.eventId = yyjson_get_uint(yyjson_obj_get(val, "eventId"));
+
+            yyjson_val *logo = yyjson_obj_get(val, "logo");
+            if (logo && !yyjson_is_null(logo)) {
+                const char* str = yyjson_get_str(logo);
+                if (str) perf.logo = str;
+            }
+
+            yyjson_val *name = yyjson_obj_get(val, "name");
+            if (name && !yyjson_is_null(name)) {
+                const char* str = yyjson_get_str(name);
+                if (str) perf.name = str;
+            }
+
+            // Parse prices
+            yyjson_val *prices = yyjson_obj_get(val, "prices");
+            if (prices) {
+                size_t pidx, pmax;
+                yyjson_val *pval;
+                yyjson_arr_foreach(prices, pidx, pmax, pval) {
+                    CITMPrice price;
+                    price.amount = yyjson_get_uint(yyjson_obj_get(pval, "amount"));
+                    price.audienceSubCategoryId = yyjson_get_uint(yyjson_obj_get(pval, "audienceSubCategoryId"));
+                    price.seatCategoryId = yyjson_get_uint(yyjson_obj_get(pval, "seatCategoryId"));
+                    perf.prices.push_back(price);
+                }
+            }
+
+            // Parse seat categories
+            yyjson_val *seatCats = yyjson_obj_get(val, "seatCategories");
+            if (seatCats) {
+                size_t scidx, scmax;
+                yyjson_val *scval;
+                yyjson_arr_foreach(seatCats, scidx, scmax, scval) {
+                    CITMSeatCategory seatCat;
+                    seatCat.seatCategoryId = yyjson_get_uint(yyjson_obj_get(scval, "seatCategoryId"));
+
+                    yyjson_val *areas = yyjson_obj_get(scval, "areas");
+                    if (areas) {
+                        size_t aidx, amax;
+                        yyjson_val *aval;
+                        yyjson_arr_foreach(areas, aidx, amax, aval) {
+                            CITMArea area;
+                            area.areaId = yyjson_get_uint(yyjson_obj_get(aval, "areaId"));
+
+                            yyjson_val *blocks = yyjson_obj_get(aval, "blockIds");
+                            if (blocks) {
+                                size_t bidx, bmax;
+                                yyjson_val *bval;
+                                yyjson_arr_foreach(blocks, bidx, bmax, bval) {
+                                    area.blockIds.push_back(yyjson_get_uint(bval));
+                                }
+                            }
+                            seatCat.areas.push_back(area);
+                        }
+                    }
+                    perf.seatCategories.push_back(seatCat);
+                }
+            }
+
+            yyjson_val *seatMapImage = yyjson_obj_get(val, "seatMapImage");
+            if (seatMapImage && !yyjson_is_null(seatMapImage)) {
+                const char* str = yyjson_get_str(seatMapImage);
+                if (str) perf.seatMapImage = str;
+            }
+
+            perf.start = yyjson_get_uint(yyjson_obj_get(val, "start"));
+            const char* venueCode = yyjson_get_str(yyjson_obj_get(val, "venueCode"));
+            if (venueCode) perf.venueCode = venueCode;
+
+            catalog.performances.push_back(perf);
+        }
+    }
+
+    yyjson_doc_free(doc);
+    return catalog;
+}
+
+void bench_yyjson_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_yyjson_parsing",
+               bench([&json_str, &result]() {
+                 try {
+                   CitmCatalog data = yyjson_deserialize(json_str);
+                   result = true;
+                 } catch (...) {
+                   result = false;
+                   printf("parse error\n");
+                 }
+               }));
+}
+#endif
+
+std::string read_file(std::string filename) {
+  printf("# Reading file %s\n", filename.c_str());
+  constexpr size_t read_size = 4096;
+  auto stream = std::ifstream(filename);
+  stream.exceptions(std::ios_base::badbit);
+
+  if (!stream) {
+    std::cerr << "Error: Failed to open file " << filename << std::endl;
+    exit(EXIT_FAILURE);
+  }
+
+  std::string out;
+  auto buf = std::string(read_size, '\0');
+  while (stream.read(&buf[0], read_size)) {
+    out.append(buf, 0, size_t(stream.gcount()));
+  }
+  out.append(buf, 0, size_t(stream.gcount()));
+  return out;
+}
+
+// Function to check if benchmark name matches any of the comma-separated filters
+bool matches_filter(const std::string& benchmark_name, const std::string& filter) {
+  if (filter.empty()) return true;
+
+  // Split filter by comma
+  size_t start = 0;
+  size_t end = filter.find(',');
+  while (end != std::string::npos) {
+    std::string token = filter.substr(start, end - start);
+    if (benchmark_name.find(token) != std::string::npos) {
+      return true;
+    }
+    start = end + 1;
+    end = filter.find(',', start);
+  }
+  // Check last token
+  std::string token = filter.substr(start);
+  return benchmark_name.find(token) != std::string::npos;
+}
+
+int main(int argc, char *argv[]) {
+  // Get the JSON file path from preprocessor or use default
+  std::string filename;
+#ifdef JSON_FILE
+  filename = JSON_FILE;
+#else
+  filename = "jsonexamples/citm_catalog.json";
+#endif
+
+  std::string json_str = read_file(filename);
+
+  // Parse command-line arguments for filter
+  std::string filter;
+  for (int i = 1; i < argc; i++) {
+    std::string arg = argv[i];
+    if (arg == "-f" && i + 1 < argc) {
+      filter = argv[i + 1];
+      printf("# Filter: %s\n", filter.c_str());
+      i++;
+    }
+  }
+
+  // If no filter provided, run all benchmarks
+  if (filter.empty()) {
+    printf("# Running all benchmarks (use -f <filter> to run specific ones)\n");
+  }
+
+  // Benchmarking the parsing
+  if (matches_filter("nlohmann", filter)) {
+    bench_nlohmann_parsing(json_str);
+  }
+#ifdef SIMDJSON_COMPETITION_RAPIDJSON
+  if (matches_filter("rapidjson", filter)) {
+    bench_rapidjson_parsing(json_str);
+  }
+#endif
+#ifdef SIMDJSON_COMPETITION_YYJSON
+  if (matches_filter("yyjson", filter)) {
+    bench_yyjson_parsing(json_str);
+  }
+#endif
+  if (matches_filter("simdjson_static_reflection", filter)) {
+    bench_simdjson_static_reflection_parsing<CitmCatalog>(json_str);
+  }
+#if SIMDJSON_STATIC_REFLECTION
+  if (matches_filter("simdjson_from", filter)) {
+    bench_simdjson_from_parsing<CitmCatalog>(json_str);
+  }
+#endif
+#ifdef SIMDJSON_RUST_VERSION
+  if (matches_filter("rust", filter)) {
+    printf("# Note: Rust/Serde parsing test\n");
+    bench_rust_parsing(json_str);
+  }
+#endif
+  return EXIT_SUCCESS;
+}

benchmark/static_reflect/citm_catalog_benchmark/benchmark_serialization_citm_catalog.cpp

@@ -11,6 +11,10 @@
 #include "nlohmann_citm_catalog_data.h"
 #include "../benchmark_utils/benchmark_helper.h"
 
+#ifdef SIMDJSON_COMPETITION_YYJSON
+#include "yyjson_citm_catalog_data.h"
+#endif
+
 #if SIMDJSON_BENCH_CPP_REFLECT
 #include <rfl.hpp>
 #include <rfl/json.hpp>
@@ -35,20 +39,15 @@ void bench_reflect_cpp(CitmCatalog &data) {
 #include "../serde-benchmark/serde_benchmark.h"
 
 void bench_rust(serde_benchmark::CitmCatalog *data) {
-  const char * output = serde_benchmark::str_from_citm(data);
-  size_t output_volume = strlen(output);
+  serde_benchmark::set_citm_data(data);
+  size_t output_volume = serde_benchmark::serialize_citm_to_string();
   printf("# output volume: %zu bytes\n", output_volume);
+
   volatile size_t measured_volume = 0;
   pretty_print(1, output_volume, "bench_rust",
-               bench([&data, &measured_volume, &output_volume]() {
-                 const char * output = serde_benchmark::str_from_citm(data);
-                 measured_volume = strlen(output);
-                 if (measured_volume != output_volume) {
-                   printf("mismatch\n");
-                 }
-                 serde_benchmark::free_str(const_cast<char*>(output));
+               bench([&measured_volume, &output_volume]() {
+                 measured_volume = serde_benchmark::serialize_citm_to_string();
                }));
-  serde_benchmark::free_str(const_cast<char*>(output));
 }
 #endif // SIMDJSON_RUST_VERSION
 
@@ -68,7 +67,55 @@ void bench_nlohmann(CitmCatalog &data) {
                }));
 }
 
+#ifdef SIMDJSON_COMPETITION_YYJSON
+void bench_yyjson(CitmCatalog &data) {
+  std::string output = yyjson_serialize_citm(data);
+  size_t output_volume = output.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(1, output_volume, "bench_yyjson",
+               bench([&data, &measured_volume, &output_volume]() {
+                 std::string output = yyjson_serialize_citm(data);
+                 measured_volume = output.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+#endif
+
+// Fair allocation variant: allocates fresh buffer each iteration (matches other libraries)
 void bench_simdjson_static_reflection(CitmCatalog &data) {
+  // First run to determine expected size
+  simdjson::builder::string_builder sb_init;
+  simdjson::builder::append(sb_init, data);
+  std::string_view p_init;
+  if(sb_init.view().get(p_init)) {
+    std::cerr << "Error!" << std::endl;
+  }
+  size_t output_volume = p_init.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_static_reflection",
+               bench([&data, &measured_volume, &output_volume]() {
+                 // Fresh allocation each iteration - fair comparison
+                 simdjson::builder::string_builder sb;
+                 simdjson::builder::append(sb, data);
+                 std::string_view p;
+                 if(sb.view().get(p)) {
+                   std::cerr << "Error!" << std::endl;
+                 }
+                 measured_volume = sb.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+
+// Optimized variant: reuses buffer across iterations (shows API potential)
+void bench_simdjson_static_reflection_reuse(CitmCatalog &data) {
   simdjson::builder::string_builder sb;
   simdjson::builder::append(sb, data);
   std::string_view p;
@@ -80,7 +127,7 @@ void bench_simdjson_static_reflection(CitmCatalog &data) {
   printf("# output volume: %zu bytes\n", output_volume);
 
   volatile size_t measured_volume = 0;
-  pretty_print(sizeof(data), output_volume, "bench_simdjson_static_reflection",
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_reuse_buffer",
                bench([&data, &measured_volume, &output_volume, &sb]() {
                  sb.clear();
                  simdjson::builder::append(sb, data);
@@ -95,25 +142,97 @@ void bench_simdjson_static_reflection(CitmCatalog &data) {
                }));
 }
 
-std::string read_file(const std::string &file_path, size_t read_size = 65536) {
+#if SIMDJSON_STATIC_REFLECTION
+// Fair allocation variant: allocates fresh string each iteration
+void bench_simdjson_to(CitmCatalog &data) {
+  // First run to determine size
+  std::string output_init;
+  if (simdjson::error_code err = simdjson::builder::to_json(data, output_init); err) {
+    std::cerr << "Error in to_json initialization!" << simdjson::error_message(err) << std::endl;
+    return;
+  }
+  size_t output_volume = output_init.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_to",
+               bench([&data, &measured_volume, &output_volume]() {
+                 // Fresh allocation each iteration - fair comparison
+                 std::string output;
+                 if (simdjson::error_code err = simdjson::builder::to_json(data, output); err) {
+                   std::cerr << "Error in to_json!" << simdjson::error_message(err) << std::endl;
+                   return;
+                 }
+                 measured_volume = output.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+
+// Optimized variant: reuses pre-allocated string
+void bench_simdjson_to_reuse(CitmCatalog &data) {
+  std::string output;
+  if (simdjson::error_code err = simdjson::builder::to_json(data, output); err) {
+    std::cerr << "Error in to_json initialization!" << simdjson::error_message(err) << std::endl;
+    return;
+  }
+  size_t output_volume = output.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  // Pre-allocate string with sufficient capacity to avoid reallocation
+  output.reserve(output_volume * 2);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_to_reuse",
+               bench([&data, &measured_volume, &output_volume, &output]() {
+                 // Reuse the pre-allocated string - avoids allocation
+                 if (simdjson::error_code err = simdjson::builder::to_json(data, output); err) {
+                   std::cerr << "Error in to_json!" << simdjson::error_message(err) << std::endl;
+                   return;
+                 }
+                 measured_volume = output.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+#endif
+
+simdjson::padded_string read_file(const std::string &file_path, size_t read_size = 65536) {
   std::ifstream stream(file_path, std::ios::binary);
   if(!stream) {
     std::cerr << "Could not open file '" << file_path << "'" << std::endl;
     exit(EXIT_FAILURE);
   }
   stream.exceptions(std::ios_base::badbit);
-  std::string out;
+  simdjson::padded_string_builder builder;
   std::string buf(read_size, '\0');
   while (stream.read(&buf[0], read_size)) {
-    out.append(buf, 0, size_t(stream.gcount()));
+    builder.append(buf.data(), size_t(stream.gcount()));
   }
-  out.append(buf, 0, size_t(stream.gcount()));
-  return out;
+  builder.append(buf.data(), size_t(stream.gcount()));
+  return builder.convert();
 }
 
-// Function to check if benchmark name contains filter substring
+// Function to check if benchmark name matches any of the comma-separated filters
 bool matches_filter(const std::string& benchmark_name, const std::string& filter) {
-  return filter.empty() || benchmark_name.find(filter) != std::string::npos;
+  if (filter.empty()) return true;
+
+  // Split filter by comma
+  size_t start = 0;
+  size_t end = filter.find(',');
+  while (end != std::string::npos) {
+    std::string token = filter.substr(start, end - start);
+    if (benchmark_name.find(token) != std::string::npos) {
+      return true;
+    }
+    start = end + 1;
+    end = filter.find(',', start);
+  }
+  // Check last token
+  std::string token = filter.substr(start);
+  return benchmark_name.find(token) != std::string::npos;
 }
 
 int main(int argc, char* argv[]) {
@@ -131,12 +250,12 @@ int main(int argc, char* argv[]) {
       }
   }
   // Testing correctness of round-trip (serialization + deserialization)
-  std::string json_str = read_file(JSON_FILE);
+  simdjson::padded_string json_str = read_file(JSON_FILE);
 
   // Loading up the data into a structure.
   simdjson::ondemand::parser parser;
   simdjson::ondemand::document doc;
-  if(parser.iterate(simdjson::pad(json_str)).get(doc)) {
+  if(parser.iterate(json_str).get(doc)) {
     std::cerr << "Error loading the document!" << std::endl;
     return EXIT_FAILURE;
   }
@@ -147,18 +266,37 @@ int main(int argc, char* argv[]) {
   }
 
   // Benchmarking the serialization
+  // Note: simdjson benchmarks include both "fair" (fresh allocation) and "reuse" (buffer reuse) variants
+  // The "fair" variants allocate fresh memory each iteration, matching other libraries' behavior
+  // The "reuse" variants demonstrate the API's potential when buffer reuse is possible
+
   if (matches_filter("nlohmann", filter)) {
     bench_nlohmann(my_struct);
   }
+#ifdef SIMDJSON_COMPETITION_YYJSON
+  if (matches_filter("yyjson", filter)) {
+    bench_yyjson(my_struct);
+  }
+#endif
   if (matches_filter("simdjson_static_reflection", filter)) {
     bench_simdjson_static_reflection(my_struct);
   }
+  if (matches_filter("simdjson_reuse", filter)) {
+    bench_simdjson_static_reflection_reuse(my_struct);
+  }
+#if SIMDJSON_STATIC_REFLECTION
+  if (matches_filter("simdjson_to", filter)) {
+    bench_simdjson_to(my_struct);
+  }
+  if (matches_filter("simdjson_to_reuse", filter)) {
+    bench_simdjson_to_reuse(my_struct);
+  }
+#endif
 #ifdef SIMDJSON_RUST_VERSION
   if (matches_filter("rust", filter)) {
-    printf("# WARNING: The Rust benchmark may not be directly comparable since it does not use an equivalent data structure.\n");
     // Create a Rust-compatible CitmCatalog structure from the JSON string
     serde_benchmark::CitmCatalog* rust_data =
-      serde_benchmark::citm_from_str(json_str.c_str(), json_str.size());
+      serde_benchmark::citm_from_str(json_str.data(), json_str.size());
 
     if (rust_data == nullptr) {
       printf("# Failed to initialize Rust data structure\n");

benchmark/static_reflect/citm_catalog_benchmark/citm_catalog_data.h

@@ -4,79 +4,65 @@
 #include <string>
 #include <vector>
 #include <map>
+#include <optional>
+#include <cstdint>
 
-struct Area {
-  int64_t id;
-  std::string name;
-  int64_t parent;
-  std::vector<int64_t> childAreas;
-  bool operator==(const Area &other) const = default;
+// Price structure - field names must match JSON keys for reflection
+struct CITMPrice {
+    uint64_t amount;
+    uint64_t audienceSubCategoryId;
+    uint64_t seatCategoryId;
+    bool operator==(const CITMPrice&) const = default;
 };
 
-struct AudienceSubCategory {
-  int64_t id;
-  std::string name;
-  int64_t parent;
-  bool operator==(const AudienceSubCategory &other) const = default;
+struct CITMArea {
+    uint64_t areaId;
+    std::vector<uint64_t> blockIds;
+    bool operator==(const CITMArea&) const = default;
 };
 
-struct Event {
-  int64_t id;
-  std::string name;
-  std::string description;
-  int64_t subTopic;
-  int64_t topic;
-  std::vector<int64_t> audience;
-  bool operator==(const Event &other) const = default;
+struct CITMSeatCategory {
+    std::vector<CITMArea> areas;
+    uint64_t seatCategoryId;
+    bool operator==(const CITMSeatCategory&) const = default;
 };
 
-struct Performance {
-  int64_t id;
-  std::string name;
-  int64_t event;
-  std::string start;
-  int64_t venueCode;
-  bool operator==(const Performance &other) const = default;
+struct CITMPerformance {
+    uint64_t id;
+    uint64_t eventId;
+    std::optional<std::string> logo;
+    std::optional<std::string> name;
+    std::vector<CITMPrice> prices;
+    std::vector<CITMSeatCategory> seatCategories;
+    std::optional<std::string> seatMapImage;
+    uint64_t start;
+    std::string venueCode;
+    bool operator==(const CITMPerformance&) const = default;
 };
 
-struct SeatCategory {
-  int64_t id;
-  std::string name;
-  std::vector<int64_t> areas;
-  bool operator==(const SeatCategory &other) const = default;
-};
-
-struct SubTopic {
-  int64_t id;
-  std::string name;
-  int64_t parent;
-  bool operator==(const SubTopic &other) const = default;
-};
-
-struct Topic {
-  int64_t id;
-  std::string name;
-  bool operator==(const Topic &other) const = default;
-};
-
-struct Venue {
-  int64_t id;
-  std::string name;
-  int64_t address;
-  bool operator==(const Venue &other) const = default;
+struct CITMEvent {
+    uint64_t id;
+    std::string name;
+    std::optional<std::string> description;
+    std::optional<std::string> logo;
+    std::vector<uint64_t> subTopicIds;
+    std::optional<std::string> subjectCode;
+    std::optional<std::string> subtitle;
+    std::vector<uint64_t> topicIds;
+    bool operator==(const CITMEvent&) const = default;
 };
 
 struct CitmCatalog {
-  std::map<std::string, Area> areas;
-  std::map<std::string, AudienceSubCategory> audienceSubCategory;
-  std::map<std::string, Event> events;
-  std::map<std::string, Performance> performances;
-  std::map<std::string, SeatCategory> seatCategory;
-  std::map<std::string, SubTopic> subTopic;
-  std::map<std::string, Topic> topic;
-  std::map<std::string, Venue> venue;
-
-  bool operator==(const CitmCatalog &other) const = default;
+    std::map<std::string, CITMEvent> events;
+    std::vector<CITMPerformance> performances;
+    bool operator==(const CitmCatalog&) const = default;
 };
 
-#endif
+// Type aliases
+using Event = CITMEvent;
+using Performance = CITMPerformance;
+using Price = CITMPrice;
+using SeatArea = CITMArea;
+using SeatCategoryInfo = CITMSeatCategory;
+
+#endif

benchmark/static_reflect/citm_catalog_benchmark/nlohmann_citm_catalog_data.h

@@ -8,164 +8,72 @@
 
 using json = nlohmann::json;
 
-// ---- Area ----
-inline void to_json(json &j, const Area &a) {
+// ---- CITMPrice ----
+inline void to_json(json &j, const CITMPrice &p) {
     j = json{
-      {"id", a.id},
-      {"name", a.name},
-      {"parent", a.parent},
-      {"childAreas", a.childAreas}
+      {"amount", p.amount},
+      {"audienceSubCategoryId", p.audienceSubCategoryId},
+      {"seatCategoryId", p.seatCategoryId}
     };
 }
-inline void from_json(const json &j, Area &a) {
-    j.at("id").get_to(a.id);
-    j.at("name").get_to(a.name);
-    j.at("parent").get_to(a.parent);
-    j.at("childAreas").get_to(a.childAreas);
-}
 
-// ---- AudienceSubCategory ----
-inline void to_json(json &j, const AudienceSubCategory &asc) {
+// ---- CITMArea ----
+inline void to_json(json &j, const CITMArea &a) {
     j = json{
-      {"id", asc.id},
-      {"name", asc.name},
-      {"parent", asc.parent}
+      {"areaId", a.areaId},
+      {"blockIds", a.blockIds}
     };
 }
-inline void from_json(const json &j, AudienceSubCategory &asc) {
-    j.at("id").get_to(asc.id);
-    j.at("name").get_to(asc.name);
-    j.at("parent").get_to(asc.parent);
-}
 
-// ---- Event ----
-inline void to_json(json &j, const Event &e) {
+// ---- CITMSeatCategory ----
+inline void to_json(json &j, const CITMSeatCategory &s) {
     j = json{
-      {"id", e.id},
-      {"name", e.name},
-      {"description", e.description},
-      {"subTopic", e.subTopic},
-      {"topic", e.topic},
-      {"audience", e.audience}
+      {"areas", s.areas},
+      {"seatCategoryId", s.seatCategoryId}
     };
 }
-inline void from_json(const json &j, Event &e) {
-    j.at("id").get_to(e.id);
-    j.at("name").get_to(e.name);
-    j.at("description").get_to(e.description);
-    j.at("subTopic").get_to(e.subTopic);
-    j.at("topic").get_to(e.topic);
-    j.at("audience").get_to(e.audience);
-}
 
-// ---- Performance ----
-inline void to_json(json &j, const Performance &p) {
+// ---- CITMPerformance ----
+inline void to_json(json &j, const CITMPerformance &p) {
     j = json{
       {"id", p.id},
+      {"eventId", p.eventId},
+      {"logo", p.logo},
       {"name", p.name},
-      {"event", p.event},
+      {"prices", p.prices},
+      {"seatCategories", p.seatCategories},
+      {"seatMapImage", p.seatMapImage},
       {"start", p.start},
       {"venueCode", p.venueCode}
     };
 }
-inline void from_json(const json &j, Performance &p) {
-    j.at("id").get_to(p.id);
-    j.at("name").get_to(p.name);
-    j.at("event").get_to(p.event);
-    j.at("start").get_to(p.start);
-    j.at("venueCode").get_to(p.venueCode);
-}
 
-// ---- SeatCategory ----
-inline void to_json(json &j, const SeatCategory &sc) {
+// ---- CITMEvent ----
+inline void to_json(json &j, const CITMEvent &e) {
     j = json{
-      {"id", sc.id},
-      {"name", sc.name},
-      {"areas", sc.areas}
+      {"id", e.id},
+      {"name", e.name},
+      {"description", e.description},
+      {"logo", e.logo},
+      {"subTopicIds", e.subTopicIds},
+      {"subjectCode", e.subjectCode},
+      {"subtitle", e.subtitle},
+      {"topicIds", e.topicIds}
     };
 }
-inline void from_json(const json &j, SeatCategory &sc) {
-    j.at("id").get_to(sc.id);
-    j.at("name").get_to(sc.name);
-    j.at("areas").get_to(sc.areas);
-}
-
-// ---- SubTopic ----
-inline void to_json(json &j, const SubTopic &st) {
-    j = json{
-      {"id", st.id},
-      {"name", st.name},
-      {"parent", st.parent}
-    };
-}
-inline void from_json(const json &j, SubTopic &st) {
-    j.at("id").get_to(st.id);
-    j.at("name").get_to(st.name);
-    j.at("parent").get_to(st.parent);
-}
-
-// ---- Topic ----
-inline void to_json(json &j, const Topic &t) {
-    j = json{
-      {"id", t.id},
-      {"name", t.name}
-    };
-}
-inline void from_json(const json &j, Topic &t) {
-    j.at("id").get_to(t.id);
-    j.at("name").get_to(t.name);
-}
-
-// ---- Venue ----
-inline void to_json(json &j, const Venue &v) {
-    j = json{
-      {"id", v.id},
-      {"name", v.name},
-      {"address", v.address}
-    };
-}
-inline void from_json(const json &j, Venue &v) {
-    j.at("id").get_to(v.id);
-    j.at("name").get_to(v.name);
-    j.at("address").get_to(v.address);
-}
 
 // ---- CitmCatalog ----
 inline void to_json(json &j, const CitmCatalog &c) {
     j = json{
-      {"areas", c.areas},
-      {"audienceSubCategory", c.audienceSubCategory},
       {"events", c.events},
-      {"performances", c.performances},
-      {"seatCategory", c.seatCategory},
-      {"subTopic", c.subTopic},
-      {"topic", c.topic},
-      {"venue", c.venue}
+      {"performances", c.performances}
     };
 }
-inline void from_json(const json &j, CitmCatalog &c) {
-    j.at("areas").get_to(c.areas);
-    j.at("audienceSubCategory").get_to(c.audienceSubCategory);
-    j.at("events").get_to(c.events);
-    j.at("performances").get_to(c.performances);
-    j.at("seatCategory").get_to(c.seatCategory);
-    j.at("subTopic").get_to(c.subTopic);
-    j.at("topic").get_to(c.topic);
-    j.at("venue").get_to(c.venue);
-}
 
-// Optional convenience functions for benchmarking
+// Serialization function
 inline std::string nlohmann_serialize(const CitmCatalog &catalog) {
     json j = catalog;
     return j.dump();
 }
-inline bool nlohmann_deserialize(const std::string &json_in, CitmCatalog &catalog) {
-    try {
-        catalog = json::parse(json_in);
-        return false; // success
-    } catch(...) {
-        return true;  // failure
-    }
-}
 
 #endif // NLOHMANN_CITM_CATALOG_DATA_H

benchmark/static_reflect/citm_catalog_benchmark/rapidjson_citm_catalog_data.h

@@ -0,0 +1,189 @@
+#ifndef RAPIDJSON_CITM_CATALOG_DATA_H
+#define RAPIDJSON_CITM_CATALOG_DATA_H
+
+#include "citm_catalog_data.h"
+#include <rapidjson/document.h>
+#include <rapidjson/writer.h>
+#include <rapidjson/stringbuffer.h>
+#include <rapidjson/error/en.h>
+
+using namespace rapidjson;
+
+// RapidJSON deserialization for CITM Catalog data
+CitmCatalog rapidjson_deserialize_citm(const std::string& json_str) {
+    Document doc;
+    doc.Parse(json_str.c_str());
+
+    if (doc.HasParseError()) {
+        throw std::runtime_error("RapidJSON parse error");
+    }
+
+    CitmCatalog catalog;
+
+    // Parse events
+    if (doc.HasMember("events") && doc["events"].IsObject()) {
+        const Value& events = doc["events"];
+        for (auto it = events.MemberBegin(); it != events.MemberEnd(); ++it) {
+            Event event;
+            const Value& ev = it->value;
+
+            if (ev.HasMember("description") && ev["description"].IsString())
+                event.description = ev["description"].GetString();
+            if (ev.HasMember("id") && ev["id"].IsUint64())
+                event.id = ev["id"].GetUint64();
+            if (ev.HasMember("logo") && ev["logo"].IsString())
+                event.logo = ev["logo"].GetString();
+            if (ev.HasMember("name") && ev["name"].IsString())
+                event.name = ev["name"].GetString();
+            if (ev.HasMember("subjectCode") && ev["subjectCode"].IsString())
+                event.subjectCode = ev["subjectCode"].GetString();
+            if (ev.HasMember("subtitle") && ev["subtitle"].IsString())
+                event.subtitle = ev["subtitle"].GetString();
+
+            if (ev.HasMember("topicIds") && ev["topicIds"].IsArray()) {
+                const Value& topics = ev["topicIds"];
+                for (SizeType j = 0; j < topics.Size(); j++) {
+                    if (topics[j].IsUint64())
+                        event.topicIds.push_back(topics[j].GetUint64());
+                }
+            }
+
+            if (ev.HasMember("subTopicIds") && ev["subTopicIds"].IsArray()) {
+                const Value& subtopics = ev["subTopicIds"];
+                for (SizeType j = 0; j < subtopics.Size(); j++) {
+                    if (subtopics[j].IsUint64())
+                        event.subTopicIds.push_back(subtopics[j].GetUint64());
+                }
+            }
+
+            catalog.events[it->name.GetString()] = event;
+        }
+    }
+
+    // Parse performances
+    if (doc.HasMember("performances") && doc["performances"].IsArray()) {
+        const Value& performances = doc["performances"];
+        for (SizeType i = 0; i < performances.Size(); i++) {
+            Performance perf;
+            const Value& p = performances[i];
+
+            if (p.HasMember("id") && p["id"].IsUint64())
+                perf.id = p["id"].GetUint64();
+            if (p.HasMember("eventId") && p["eventId"].IsUint64())
+                perf.eventId = p["eventId"].GetUint64();
+            if (p.HasMember("start") && p["start"].IsUint64())
+                perf.start = p["start"].GetUint64();
+            if (p.HasMember("venueCode") && p["venueCode"].IsString())
+                perf.venueCode = p["venueCode"].GetString();
+            if (p.HasMember("name") && p["name"].IsString())
+                perf.name = p["name"].GetString();
+
+            catalog.performances.push_back(perf);
+        }
+    }
+
+    // Parse other string maps
+    auto parseStringMap = [&doc](const char* key, std::map<std::string, std::string>& target) {
+        if (doc.HasMember(key) && doc[key].IsObject()) {
+            const Value& obj = doc[key];
+            for (auto it = obj.MemberBegin(); it != obj.MemberEnd(); ++it) {
+                if (it->value.IsString()) {
+                    target[it->name.GetString()] = it->value.GetString();
+                }
+            }
+        }
+    };
+
+    return catalog;
+}
+
+// RapidJSON serialization for CITM Catalog data
+std::string rapidjson_serialize_citm(const CitmCatalog& catalog) {
+    Document doc;
+    doc.SetObject();
+    Document::AllocatorType& allocator = doc.GetAllocator();
+
+    // Serialize events
+    Value events_obj(kObjectType);
+    for (const auto& [key, event] : catalog.events) {
+        Value event_obj(kObjectType);
+
+        if (event.description) {
+            Value desc;
+            desc.SetString(event.description->c_str(), allocator);
+            event_obj.AddMember("description", desc, allocator);
+        }
+
+        event_obj.AddMember("id", event.id, allocator);
+
+        if (event.logo) {
+            Value logo;
+            logo.SetString(event.logo->c_str(), allocator);
+            event_obj.AddMember("logo", logo, allocator);
+        }
+
+        Value name;
+        name.SetString(event.name.c_str(), allocator);
+        event_obj.AddMember("name", name, allocator);
+
+        if (event.subjectCode) {
+            Value subject;
+            subject.SetString(event.subjectCode->c_str(), allocator);
+            event_obj.AddMember("subjectCode", subject, allocator);
+        }
+
+        if (event.subtitle) {
+            Value subtitle;
+            subtitle.SetString(event.subtitle->c_str(), allocator);
+            event_obj.AddMember("subtitle", subtitle, allocator);
+        }
+
+        Value topicIds(kArrayType);
+        for (uint64_t id : event.topicIds) {
+            topicIds.PushBack(id, allocator);
+        }
+        event_obj.AddMember("topicIds", topicIds, allocator);
+
+        Value subTopicIds(kArrayType);
+        for (uint64_t id : event.subTopicIds) {
+            subTopicIds.PushBack(id, allocator);
+        }
+        event_obj.AddMember("subTopicIds", subTopicIds, allocator);
+
+        Value key_val;
+        key_val.SetString(key.c_str(), allocator);
+        events_obj.AddMember(key_val, event_obj, allocator);
+    }
+    doc.AddMember("events", events_obj, allocator);
+
+    // Serialize performances
+    Value performances_array(kArrayType);
+    for (const auto& perf : catalog.performances) {
+        Value perf_obj(kObjectType);
+        perf_obj.AddMember("id", perf.id, allocator);
+        perf_obj.AddMember("eventId", perf.eventId, allocator);
+        perf_obj.AddMember("start", perf.start, allocator);
+
+        Value venue;
+        venue.SetString(perf.venueCode.c_str(), allocator);
+        perf_obj.AddMember("venueCode", venue, allocator);
+
+        if (perf.name) {
+            Value name;
+            name.SetString(perf.name->c_str(), allocator);
+            perf_obj.AddMember("name", name, allocator);
+        }
+
+
+        performances_array.PushBack(perf_obj, allocator);
+    }
+    doc.AddMember("performances", performances_array, allocator);
+
+    StringBuffer buffer;
+    Writer<StringBuffer> writer(buffer);
+    doc.Accept(writer);
+
+    return buffer.GetString();
+}
+
+#endif // RAPIDJSON_CITM_CATALOG_DATA_H

benchmark/static_reflect/citm_catalog_benchmark/yyjson_citm_catalog_data.h

@@ -0,0 +1,231 @@
+#ifndef YYJSON_CITM_CATALOG_DATA_H
+#define YYJSON_CITM_CATALOG_DATA_H
+
+#include "citm_catalog_data.h"
+#include <yyjson.h>
+#include <string>
+#include <stdexcept>
+
+// yyjson deserialization for CITM Catalog data
+// Matches C++ CitmCatalog struct (only events + performances)
+CitmCatalog yyjson_deserialize_citm(const std::string &json_str) {
+    CitmCatalog catalog;
+
+    yyjson_doc *doc = yyjson_read(json_str.c_str(), json_str.size(), 0);
+    if (!doc) {
+        throw std::runtime_error("yyjson parse error");
+    }
+
+    yyjson_val *root = yyjson_doc_get_root(doc);
+    if (!root) {
+        yyjson_doc_free(doc);
+        return catalog;
+    }
+
+    // Parse events
+    yyjson_val *events_val = yyjson_obj_get(root, "events");
+    if (events_val && yyjson_is_obj(events_val)) {
+        size_t idx, max;
+        yyjson_val *key, *val;
+        yyjson_obj_foreach(events_val, idx, max, key, val) {
+            CITMEvent event;
+
+            yyjson_val *v;
+            v = yyjson_obj_get(val, "description");
+            if (v && yyjson_is_str(v)) event.description = yyjson_get_str(v);
+
+            v = yyjson_obj_get(val, "id");
+            if (v && yyjson_is_uint(v)) event.id = yyjson_get_uint(v);
+
+            v = yyjson_obj_get(val, "logo");
+            if (v && yyjson_is_str(v)) event.logo = yyjson_get_str(v);
+
+            v = yyjson_obj_get(val, "name");
+            if (v && yyjson_is_str(v)) event.name = yyjson_get_str(v);
+
+            v = yyjson_obj_get(val, "subjectCode");
+            if (v && yyjson_is_str(v)) event.subjectCode = yyjson_get_str(v);
+
+            v = yyjson_obj_get(val, "subtitle");
+            if (v && yyjson_is_str(v)) event.subtitle = yyjson_get_str(v);
+
+            // Parse topicIds array
+            v = yyjson_obj_get(val, "topicIds");
+            if (v && yyjson_is_arr(v)) {
+                size_t arr_idx, arr_max;
+                yyjson_val *arr_val;
+                yyjson_arr_foreach(v, arr_idx, arr_max, arr_val) {
+                    if (yyjson_is_uint(arr_val))
+                        event.topicIds.push_back(yyjson_get_uint(arr_val));
+                }
+            }
+
+            // Parse subTopicIds array
+            v = yyjson_obj_get(val, "subTopicIds");
+            if (v && yyjson_is_arr(v)) {
+                size_t arr_idx, arr_max;
+                yyjson_val *arr_val;
+                yyjson_arr_foreach(v, arr_idx, arr_max, arr_val) {
+                    if (yyjson_is_uint(arr_val))
+                        event.subTopicIds.push_back(yyjson_get_uint(arr_val));
+                }
+            }
+
+            if (yyjson_is_str(key))
+                catalog.events[yyjson_get_str(key)] = event;
+        }
+    }
+
+    // Parse performances (simplified - full parsing would need prices/seatCategories)
+    yyjson_val *performances_val = yyjson_obj_get(root, "performances");
+    if (performances_val && yyjson_is_arr(performances_val)) {
+        size_t idx, max;
+        yyjson_val *perf_val;
+        yyjson_arr_foreach(performances_val, idx, max, perf_val) {
+            CITMPerformance perf;
+
+            yyjson_val *v;
+            v = yyjson_obj_get(perf_val, "id");
+            if (v && yyjson_is_uint(v)) perf.id = yyjson_get_uint(v);
+
+            v = yyjson_obj_get(perf_val, "eventId");
+            if (v && yyjson_is_uint(v)) perf.eventId = yyjson_get_uint(v);
+
+            v = yyjson_obj_get(perf_val, "start");
+            if (v && yyjson_is_uint(v)) perf.start = yyjson_get_uint(v);
+
+            v = yyjson_obj_get(perf_val, "venueCode");
+            if (v && yyjson_is_str(v)) perf.venueCode = yyjson_get_str(v);
+
+            v = yyjson_obj_get(perf_val, "name");
+            if (v && yyjson_is_str(v)) perf.name = yyjson_get_str(v);
+
+            v = yyjson_obj_get(perf_val, "logo");
+            if (v && yyjson_is_str(v)) perf.logo = yyjson_get_str(v);
+
+            v = yyjson_obj_get(perf_val, "seatMapImage");
+            if (v && yyjson_is_str(v)) perf.seatMapImage = yyjson_get_str(v);
+
+            // Note: prices and seatCategories parsing omitted for brevity
+            // The serialization benchmark uses data loaded by simdjson
+
+            catalog.performances.push_back(perf);
+        }
+    }
+
+    yyjson_doc_free(doc);
+    return catalog;
+}
+
+// Helper to add optional string field
+static inline void yyjson_add_optional_str(yyjson_mut_doc *doc, yyjson_mut_val *obj,
+                                           const char *key, const std::optional<std::string> &val) {
+    if (val.has_value()) {
+        yyjson_mut_obj_add_str(doc, obj, key, val->c_str());
+    } else {
+        yyjson_mut_obj_add_null(doc, obj, key);
+    }
+}
+
+// yyjson serialization for CITM Catalog data
+// Matches C++ CitmCatalog struct exactly (only events + performances)
+std::string yyjson_serialize_citm(const CitmCatalog &catalog) {
+    yyjson_mut_doc *doc = yyjson_mut_doc_new(NULL);
+    yyjson_mut_val *root = yyjson_mut_obj(doc);
+    yyjson_mut_doc_set_root(doc, root);
+
+    // Create events object
+    yyjson_mut_val *events_obj = yyjson_mut_obj(doc);
+    for (const auto& [key, event] : catalog.events) {
+        yyjson_mut_val *event_obj = yyjson_mut_obj(doc);
+
+        yyjson_add_optional_str(doc, event_obj, "description", event.description);
+        yyjson_mut_obj_add_uint(doc, event_obj, "id", event.id);
+        yyjson_add_optional_str(doc, event_obj, "logo", event.logo);
+        // name is not optional in CITMEvent
+        yyjson_mut_obj_add_str(doc, event_obj, "name", event.name.c_str());
+
+        // Add subTopicIds array
+        yyjson_mut_val *subtopic_ids = yyjson_mut_arr(doc);
+        for (uint64_t id : event.subTopicIds) {
+            yyjson_mut_arr_add_uint(doc, subtopic_ids, id);
+        }
+        yyjson_mut_obj_add_val(doc, event_obj, "subTopicIds", subtopic_ids);
+
+        yyjson_add_optional_str(doc, event_obj, "subjectCode", event.subjectCode);
+        yyjson_add_optional_str(doc, event_obj, "subtitle", event.subtitle);
+
+        // Add topicIds array
+        yyjson_mut_val *topic_ids = yyjson_mut_arr(doc);
+        for (uint64_t id : event.topicIds) {
+            yyjson_mut_arr_add_uint(doc, topic_ids, id);
+        }
+        yyjson_mut_obj_add_val(doc, event_obj, "topicIds", topic_ids);
+
+        yyjson_mut_obj_add_val(doc, events_obj, key.c_str(), event_obj);
+    }
+    yyjson_mut_obj_add_val(doc, root, "events", events_obj);
+
+    // Create performances array
+    yyjson_mut_val *performances_array = yyjson_mut_arr(doc);
+    for (const auto& perf : catalog.performances) {
+        yyjson_mut_val *perf_obj = yyjson_mut_obj(doc);
+
+        yyjson_mut_obj_add_uint(doc, perf_obj, "eventId", perf.eventId);
+        yyjson_mut_obj_add_uint(doc, perf_obj, "id", perf.id);
+        yyjson_add_optional_str(doc, perf_obj, "logo", perf.logo);
+        yyjson_add_optional_str(doc, perf_obj, "name", perf.name);
+
+        // Add prices array
+        yyjson_mut_val *prices_array = yyjson_mut_arr(doc);
+        for (const auto& price : perf.prices) {
+            yyjson_mut_val *price_obj = yyjson_mut_obj(doc);
+            yyjson_mut_obj_add_uint(doc, price_obj, "amount", price.amount);
+            yyjson_mut_obj_add_uint(doc, price_obj, "audienceSubCategoryId", price.audienceSubCategoryId);
+            yyjson_mut_obj_add_uint(doc, price_obj, "seatCategoryId", price.seatCategoryId);
+            yyjson_mut_arr_append(prices_array, price_obj);
+        }
+        yyjson_mut_obj_add_val(doc, perf_obj, "prices", prices_array);
+
+        // Add seatCategories array
+        yyjson_mut_val *seat_cats_array = yyjson_mut_arr(doc);
+        for (const auto& seatCat : perf.seatCategories) {
+            yyjson_mut_val *seat_cat_obj = yyjson_mut_obj(doc);
+
+            // Add areas array
+            yyjson_mut_val *areas_array = yyjson_mut_arr(doc);
+            for (const auto& area : seatCat.areas) {
+                yyjson_mut_val *area_obj = yyjson_mut_obj(doc);
+                yyjson_mut_obj_add_uint(doc, area_obj, "areaId", area.areaId);
+
+                yyjson_mut_val *block_ids = yyjson_mut_arr(doc);
+                for (uint64_t blockId : area.blockIds) {
+                    yyjson_mut_arr_add_uint(doc, block_ids, blockId);
+                }
+                yyjson_mut_obj_add_val(doc, area_obj, "blockIds", block_ids);
+                yyjson_mut_arr_append(areas_array, area_obj);
+            }
+            yyjson_mut_obj_add_val(doc, seat_cat_obj, "areas", areas_array);
+            yyjson_mut_obj_add_uint(doc, seat_cat_obj, "seatCategoryId", seatCat.seatCategoryId);
+            yyjson_mut_arr_append(seat_cats_array, seat_cat_obj);
+        }
+        yyjson_mut_obj_add_val(doc, perf_obj, "seatCategories", seat_cats_array);
+
+        yyjson_add_optional_str(doc, perf_obj, "seatMapImage", perf.seatMapImage);
+        yyjson_mut_obj_add_uint(doc, perf_obj, "start", perf.start);
+        yyjson_mut_obj_add_str(doc, perf_obj, "venueCode", perf.venueCode.c_str());
+
+        yyjson_mut_arr_append(performances_array, perf_obj);
+    }
+    yyjson_mut_obj_add_val(doc, root, "performances", performances_array);
+
+    // Write to string
+    char *json_output = yyjson_mut_write(doc, 0, NULL);
+    std::string result(json_output);
+    free(json_output);
+    yyjson_mut_doc_free(doc);
+
+    return result;
+}
+
+#endif // YYJSON_CITM_CATALOG_DATA_H

benchmark/static_reflect/serde-benchmark/lib.rs

@@ -5,405 +5,165 @@ extern crate libc;
 use libc::{c_char, size_t};
 use serde::{Serialize, Deserialize};
 use std::{collections::HashMap, ffi::CString, ptr, slice};
-use serde::de::{self, Deserializer};
-/******************************************************/
-/******************************************************/
-/**
- * Warning: the C++ code may not generate the same JSON.
- */
- /******************************************************/
- /******************************************************/
 
-// This has no equivalent in C++:
-#[derive(Serialize, Deserialize)]
-pub struct Metadata {
-    result_type: String,
-    iso_language_code: String,
-}
+//==============================================================================
+// Twitter Benchmark Structures
+// These match the C++ TwitterData structures exactly
+//==============================================================================
 
 #[derive(Serialize, Deserialize)]
 pub struct User {
-    id: i64,
-    id_str: String,
+    id: u64,
     name: String,
     screen_name: String,
     location: String,
     description: String,
-    // C++ does not have those:
-    // url: Option<String>,
-    //protected: bool,
-    //listed_count: i64,
-    //created_at: String,
-    //favourites_count: i64,
-    //utc_offset: Option<i64>,
-    //time_zone: Option<String>,
-    //geo_enabled: bool,
     verified: bool,
-    followers_count: i64,
-    friends_count: i64,
-    statuses_count: i64,
-    // C++ does not have those:
-    //lang: String,
-    //profile_background_color: String,
-    //profile_background_image_url: String,
-    //profile_background_image_url_https: String,
-    //profile_background_tile: bool,
-    //profile_image_url: String,
-    //profile_image_url_https: String,
-    //profile_banner_url: Option<String>,
-    //profile_link_color: String,
-    //profile_sidebar_border_color: String,
-    //profile_sidebar_fill_color: String,
-    //profile_text_color: String,
-    //profile_use_background_image: bool,
-    //default_profile: bool,
-    //default_profile_image: bool,
-    //following: bool,
-    //follow_request_sent: bool,
-    //notifications: bool,
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct Hashtag {
-    text: String,
-
-    // C++ has those but D. Lemire does not know what they are, they don't appear in the JSON:
-    // int64_t indices_start;
-    // int64_t indices_end;
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct Url {
-    url: String,
-    expanded_url: String,
-    display_url: String,
-    // C++ has those but D. Lemire does not know what they are, they don't appear in the JSON:
-    // int64_t indices_start;
-    // int64_t indices_end;
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct UserMention {
-    id: i64,
-    name: String,
-    screen_name: String,
-    // Not in the C++ equivalent:
-    //id_str: String,
-    //indices: Vec<i64>,
-    // C++ has those but D. Lemire does not know what they are, they don't appear in the JSON:
-    // int64_t indices_start;
-    // int64_t indices_end;
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct Entities {
-    hashtags: Vec<Hashtag>,
-    urls: Vec<Url>,
-    user_mentions: Vec<UserMention>,
+    followers_count: u64,
+    friends_count: u64,
+    statuses_count: u64,
 }
 
 #[derive(Serialize, Deserialize)]
 pub struct Status {
     created_at: String,
-    id: i64,
+    id: u64,
     text: String,
     user: User,
-    entities: Entities,
-    retweet_count: i64,
-    favorite_count: i64,
-    favorited: bool,
-    retweeted: bool,
-    // None of these are in the C++ equivalent:
-    /*
-    metadata: Metadata,
-    id_str: String,
-    source: String,
-    truncated: bool,
-    in_reply_to_status_id: Option<i64>,
-    in_reply_to_status_id_str: Option<String>,
-    in_reply_to_user_id: Option<i64>,
-    in_reply_to_user_id_str: Option<String>,
-    in_reply_to_screen_name: Option<String>,
-    geo: Option<String>,
-    coordinates: Option<String>,
-    place: Option<String>,
-    contributors: Option<String>,
-    lang: String,
-    */
+    retweet_count: u64,
+    favorite_count: u64,
 }
 
 #[derive(Serialize, Deserialize)]
 pub struct TwitterData {
     statuses: Vec<Status>,
 }
+static mut TWITTER_DATA: *mut TwitterData = std::ptr::null_mut();
 
 #[no_mangle]
-pub unsafe extern "C" fn  twitter_from_str(raw_input: *const c_char, raw_input_length: size_t) -> *mut TwitterData {
-  let input = std::str::from_utf8_unchecked(slice::from_raw_parts(raw_input as *const u8, raw_input_length));
-  match serde_json::from_str(&input) {
-    Ok(result) => Box::into_raw(Box::new(result)),
-    Err(_) => std::ptr::null_mut(),
-  }
+pub unsafe extern "C" fn twitter_from_str(raw_input: *const c_char, raw_input_length: size_t) -> *mut TwitterData {
+    let input = std::str::from_utf8_unchecked(slice::from_raw_parts(raw_input as *const u8, raw_input_length));
+    match serde_json::from_str(&input) {
+        Ok(result) => Box::into_raw(Box::new(result)),
+        Err(_) => std::ptr::null_mut(),
+    }
 }
 
 #[no_mangle]
-pub unsafe extern "C" fn str_from_twitter(raw: *mut TwitterData) -> *const c_char {
-  let twitter_thing = { &*raw };
-  let serialized = serde_json::to_string(&twitter_thing).unwrap();
-  return std::ffi::CString::new(serialized.as_str()).unwrap().into_raw()
+pub unsafe extern "C" fn set_twitter_data(raw: *mut TwitterData) {
+    TWITTER_DATA = raw;
 }
 
+#[no_mangle]
+pub unsafe extern "C" fn serialize_twitter_to_string() -> usize {
+    if TWITTER_DATA.is_null() {
+        return 0;
+    }
+    let data = &*TWITTER_DATA;
+    serde_json::to_string(data).unwrap().len()
+}
 
 #[no_mangle]
 pub unsafe extern "C" fn free_twitter(raw: *mut TwitterData) {
-  if raw.is_null() {
-    return;
-  }
-
-  drop(Box::from_raw(raw))
+    if raw.is_null() {
+        return;
+    }
+    drop(Box::from_raw(raw))
 }
 
-
 #[no_mangle]
 pub unsafe extern fn free_string(ptr: *const c_char) {
     let _ = std::ffi::CString::from_raw(ptr as *mut _);
 }
 
-// Functions associated with the CitmCatalog benchmark
+//==============================================================================
+// CITM Catalog Benchmark Structures
+// These match the C++ CitmCatalog structures EXACTLY for fair comparison
+//==============================================================================
 
-#[derive(Serialize, Deserialize)]
-pub struct Area {
-    pub id: i64,
-    pub name: Option<String>,  // Changed to Option
-    pub parent: i64,
-    #[serde(rename = "childAreas")]
-    pub child_areas: Vec<i64>,
+/// Matches C++ CITMPrice struct exactly
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct CITMPrice {
+    pub amount: u64,
+    #[serde(rename = "audienceSubCategoryId")]
+    pub audience_sub_category_id: u64,
+    #[serde(rename = "seatCategoryId")]
+    pub seat_category_id: u64,
 }
 
-#[derive(Serialize, Deserialize)]
-pub struct AudienceSubCategory {
-    pub id: i64,
-    pub name: Option<String>,  // Changed to Option
-    pub parent: i64,
+/// Matches C++ CITMArea struct exactly
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct CITMArea {
+    #[serde(rename = "areaId")]
+    pub area_id: u64,
+    #[serde(rename = "blockIds")]
+    pub block_ids: Vec<u64>,
 }
 
-#[derive(Serialize, Deserialize, Debug)]
-pub struct Event {
-    #[serde(default)]
-    pub description: Option<String>,
-    pub id: i64,
+/// Matches C++ CITMSeatCategory struct exactly
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct CITMSeatCategory {
+    pub areas: Vec<CITMArea>,
+    #[serde(rename = "seatCategoryId")]
+    pub seat_category_id: u64,
+}
+
+/// Matches C++ CITMPerformance struct exactly
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct CITMPerformance {
+    pub id: u64,
+    #[serde(rename = "eventId")]
+    pub event_id: u64,
     #[serde(default)]
     pub logo: Option<String>,
     #[serde(default)]
     pub name: Option<String>,
+    pub prices: Vec<CITMPrice>,
+    #[serde(rename = "seatCategories")]
+    pub seat_categories: Vec<CITMSeatCategory>,
     #[serde(default)]
-    pub subTopicIds: Vec<i64>,
+    #[serde(rename = "seatMapImage")]
+    pub seat_map_image: Option<String>,
+    pub start: u64,
+    #[serde(rename = "venueCode")]
+    pub venue_code: String,
+}
+
+/// Matches C++ CITMEvent struct exactly
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct CITMEvent {
+    pub id: u64,
     #[serde(default)]
-    pub subjectCode: Option<String>,
+    pub name: Option<String>,
+    #[serde(default)]
+    pub description: Option<String>,
+    #[serde(default)]
+    pub logo: Option<String>,
+    #[serde(default)]
+    #[serde(rename = "subTopicIds")]
+    pub sub_topic_ids: Vec<u64>,
+    #[serde(default)]
+    #[serde(rename = "subjectCode")]
+    pub subject_code: Option<String>,
     #[serde(default)]
     pub subtitle: Option<String>,
     #[serde(default)]
-    pub topicIds: Vec<i64>,
-    // Add a catch-all for any other fields
-    #[serde(flatten)]
-    pub extra: HashMap<String, serde_json::Value>,
-}
-
-#[derive(Serialize, Deserialize, Debug)]
-pub struct Performance {
-    #[serde(default)]
-    pub id: i64,
-
-    #[serde(default)]
-    pub name: Option<String>,
-
-    #[serde(default)]
-    pub event: i64,
-
-    // This is the key fix - accept any JSON value type for timestamps
-    // This allows both string dates and integer timestamps (line 3511)
-    #[serde(default)]
-    pub start: serde_json::Value,
-
-    #[serde(rename = "venueCode")]
-    pub venue_code: String,
-
-    // Add a catch-all for any other fields
-    #[serde(flatten)]
-    pub extra: HashMap<String, serde_json::Value>,
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct SeatCategory {
-    pub id: i64,
-    pub name: Option<String>,  // Changed to Option
-    pub areas: Vec<i64>,
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct SubTopic {
-    pub id: i64,
-    pub name: Option<String>,  // Changed to Option
-    pub parent: i64,
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct Topic {
-    pub id: i64,
-    pub name: Option<String>,  // Changed to Option
-}
-
-#[derive(Serialize, Deserialize)]
-pub struct Venue {
-    pub id: i64,
-    pub name: Option<String>,  // Changed to Option
-    pub address: i64,
-}
-
-// Custom deserializers
-fn deserialize_string_to_area<'de, D>(deserializer: D) -> Result<HashMap<String, Area>, D::Error>
-where D: Deserializer<'de> {
-    let string_map: HashMap<String, String> = HashMap::deserialize(deserializer)?;
-    let mut result = HashMap::new();
-
-    for (id, name) in string_map {
-        let id_num = id.parse::<i64>().unwrap_or(0);
-        result.insert(id.clone(), Area {
-            id: id_num,
-            name: Some(name),
-            parent: 0,
-            child_areas: Vec::new(),
-        });
-    }
-
-    Ok(result)
-}
-
-fn deserialize_string_to_audience_subcategory<'de, D>(deserializer: D) -> Result<HashMap<String, AudienceSubCategory>, D::Error>
-where D: Deserializer<'de> {
-    let string_map: HashMap<String, String> = HashMap::deserialize(deserializer)?;
-    let mut result = HashMap::new();
-
-    for (id, name) in string_map {
-        let id_num = id.parse::<i64>().unwrap_or(0);
-        result.insert(id.clone(), AudienceSubCategory {
-            id: id_num,
-            name: Some(name),
-            parent: 0,
-        });
-    }
-
-    Ok(result)
-}
-
-fn deserialize_string_to_seat_category<'de, D>(deserializer: D) -> Result<HashMap<String, SeatCategory>, D::Error>
-where D: Deserializer<'de> {
-    let string_map: HashMap<String, String> = HashMap::deserialize(deserializer)?;
-    let mut result = HashMap::new();
-
-    for (id, name) in string_map {
-        let id_num = id.parse::<i64>().unwrap_or(0);
-        result.insert(id.clone(), SeatCategory {
-            id: id_num,
-            name: Some(name),
-            areas: Vec::new(),
-        });
-    }
-
-    Ok(result)
-}
-
-fn deserialize_string_to_subtopic<'de, D>(deserializer: D) -> Result<HashMap<String, SubTopic>, D::Error>
-where D: Deserializer<'de> {
-    let string_map: HashMap<String, String> = HashMap::deserialize(deserializer)?;
-    let mut result = HashMap::new();
-
-    for (id, name) in string_map {
-        let id_num = id.parse::<i64>().unwrap_or(0);
-        result.insert(id.clone(), SubTopic {
-            id: id_num,
-            name: Some(name),
-            parent: 0,
-        });
-    }
-
-    Ok(result)
-}
-
-fn deserialize_string_to_topic<'de, D>(deserializer: D) -> Result<HashMap<String, Topic>, D::Error>
-where D: Deserializer<'de> {
-    let string_map: HashMap<String, String> = HashMap::deserialize(deserializer)?;
-    let mut result = HashMap::new();
-
-    for (id, name) in string_map {
-        let id_num = id.parse::<i64>().unwrap_or(0);
-        result.insert(id.clone(), Topic {
-            id: id_num,
-            name: Some(name),
-        });
-    }
-
-    Ok(result)
-}
-
-fn deserialize_string_to_venue<'de, D>(deserializer: D) -> Result<HashMap<String, Venue>, D::Error>
-where D: Deserializer<'de> {
-    let string_map: HashMap<String, String> = HashMap::deserialize(deserializer)?;
-    let mut result = HashMap::new();
-
-    for (id, name) in string_map {
-        result.insert(id.clone(), Venue {
-            id: 0,
-            name: Some(name),
-            address: 0,
-        });
-    }
-
-    Ok(result)
+    #[serde(rename = "topicIds")]
+    pub topic_ids: Vec<u64>,
 }
 
+/// Matches C++ CitmCatalog struct exactly - ONLY events and performances
+/// This is the key fix: we serialize only what C++ serializes
 #[derive(Serialize, Deserialize, Debug)]
 pub struct CitmCatalog {
-    #[serde(rename = "areaNames")]
-    pub area_names: HashMap<String, String>,
-
-    #[serde(rename = "audienceSubCategoryNames")]
-    pub audience_subcategory_names: HashMap<String, String>,
-
-    #[serde(default)]
-    #[serde(rename = "blockNames")]
-    pub block_names: HashMap<String, String>,
-
-    pub events: HashMap<String, Event>,
-
-    #[serde(default)]
-    pub performances: Vec<Performance>,
-
-    #[serde(rename = "seatCategoryNames")]
-    pub seat_category_names: HashMap<String, String>,
-
-    #[serde(rename = "subTopicNames")]
-    pub subtopic_names: HashMap<String, String>,
-
-    #[serde(default)]
-    #[serde(rename = "subjectNames")]
-    pub subject_names: HashMap<String, String>,
-
-    #[serde(rename = "topicNames")]
-    pub topic_names: HashMap<String, String>,
-
-    #[serde(rename = "topicSubTopics")]
-    pub topic_subtopics: HashMap<String, Vec<i64>>,
-
-    #[serde(rename = "venueNames")]
-    pub venue_names: HashMap<String, String>,
-
-    // Catch-all for other fields
-    #[serde(flatten)]
-    pub extra: HashMap<String, serde_json::Value>,
+    pub events: HashMap<String, CITMEvent>,
+    pub performances: Vec<CITMPerformance>,
 }
 
+static mut CITM_DATA: *mut CitmCatalog = std::ptr::null_mut();
+
 /// Creates a CitmCatalog from a JSON string (UTF-8 encoded).
+/// Only extracts events and performances to match C++ behavior.
 #[no_mangle]
 pub unsafe extern "C" fn citm_from_str(
     raw_input: *const c_char,
@@ -414,7 +174,6 @@ pub unsafe extern "C" fn citm_from_str(
         return ptr::null_mut();
     }
 
-    // Convert the raw pointer + length into a Rust slice
     let bytes = slice::from_raw_parts(raw_input as *const u8, raw_input_length);
     let input_str = match std::str::from_utf8(bytes) {
         Ok(s) => s,
@@ -424,12 +183,23 @@ pub unsafe extern "C" fn citm_from_str(
         }
     };
 
-    // Try deserializing the input string into CitmCatalog
-    match serde_json::from_str::<CitmCatalog>(input_str) {
-        Ok(catalog) => Box::into_raw(Box::new(catalog)),
+    // Parse the full JSON to extract only events and performances
+    match serde_json::from_str::<serde_json::Value>(input_str) {
+        Ok(full_json) => {
+            // Extract only the fields we need (matching C++ behavior)
+            let events: HashMap<String, CITMEvent> = full_json.get("events")
+                .and_then(|v| serde_json::from_value(v.clone()).ok())
+                .unwrap_or_default();
+
+            let performances: Vec<CITMPerformance> = full_json.get("performances")
+                .and_then(|v| serde_json::from_value(v.clone()).ok())
+                .unwrap_or_default();
+
+            let catalog = CitmCatalog { events, performances };
+            Box::into_raw(Box::new(catalog))
+        },
         Err(e) => {
             eprintln!("Error deserializing JSON: {}", e);
-            eprintln!("JSON snippet (first 200 chars): {:.200}...", input_str);
             ptr::null_mut()
         }
     }
@@ -437,30 +207,17 @@ pub unsafe extern "C" fn citm_from_str(
 
 /// Serializes a CitmCatalog into a JSON string (UTF-8).
 #[no_mangle]
-pub unsafe extern "C" fn str_from_citm(raw_catalog: *mut CitmCatalog) -> *mut c_char {
-    if raw_catalog.is_null() {
-        eprintln!("Error: Catalog pointer is null");
-        return ptr::null_mut();
-    }
+pub unsafe extern "C" fn set_citm_data(raw: *mut CitmCatalog) {
+    CITM_DATA = raw;
+}
 
-    // Fix: Actually serialize the catalog
-    let catalog = &*raw_catalog;
-
-    match serde_json::to_string(catalog) {
-        Ok(serialized) => {
-            match CString::new(serialized) {
-                Ok(cstr) => cstr.into_raw(),
-                Err(e) => {
-                    eprintln!("Error creating CString: {}", e);
-                    ptr::null_mut()
-                }
-            }
-        },
-        Err(e) => {
-            eprintln!("Error serializing catalog to JSON: {}", e);
-            ptr::null_mut()
-        }
+#[no_mangle]
+pub unsafe extern "C" fn serialize_citm_to_string() -> usize {
+    if CITM_DATA.is_null() {
+        return 0;
     }
+    let data = &*CITM_DATA;
+    return serde_json::to_string(data).unwrap().len();
 }
 
 /// Frees the CitmCatalog pointer.
@@ -475,8 +232,120 @@ pub unsafe extern "C" fn free_citm(raw_catalog: *mut CitmCatalog) {
 pub extern "C" fn free_str(ptr: *mut c_char) {
     if !ptr.is_null() {
         unsafe {
-            // Convert back into a CString, which automatically frees the memory
             let _ = CString::from_raw(ptr);
         }
     }
-}
+}
+
+//==============================================================================
+// FFI Overhead Measurement Functions
+// These allow measuring the actual FFI overhead vs pure Rust serialization
+//==============================================================================
+
+/// Result structure for FFI overhead measurement
+#[repr(C)]
+pub struct FfiOverheadResult {
+    /// Time in nanoseconds for pure serde_json::to_string() (no FFI overhead)
+    pub pure_serde_ns: u64,
+    /// Time in nanoseconds for serde + CString conversion
+    pub serde_plus_cstring_ns: u64,
+    /// Number of iterations performed
+    pub iterations: u64,
+    /// Output size in bytes (for verification)
+    pub output_size: u64,
+}
+
+/// Prevents compiler from optimizing away the value
+/// Works on stable Rust (unlike std::hint::black_box which is unstable)
+#[inline(never)]
+fn black_box<T>(dummy: T) -> T {
+    unsafe {
+        let ret = std::ptr::read_volatile(&dummy);
+        std::mem::forget(dummy);
+        ret
+    }
+}
+
+/// Measures FFI overhead for Twitter serialization.
+/// Performs `iterations` serializations entirely in Rust and returns timing data.
+/// This allows comparing against per-call FFI overhead.
+#[no_mangle]
+pub unsafe extern "C" fn measure_twitter_ffi_overhead(
+    raw: *mut TwitterData,
+    iterations: u64
+) -> FfiOverheadResult {
+    use std::time::Instant;
+
+    let twitter_data = &*raw;
+    let output_size: u64;
+
+    // Warm-up run
+    let warmup = serde_json::to_string(&twitter_data).unwrap();
+    output_size = warmup.len() as u64;
+
+    // Measure pure serde_json::to_string() - no CString conversion
+    let start_pure = Instant::now();
+    for _ in 0..iterations {
+        let serialized = serde_json::to_string(&twitter_data).unwrap();
+        // Prevent optimization from eliminating the work
+        black_box(&serialized);
+    }
+    let pure_serde_ns = start_pure.elapsed().as_nanos() as u64;
+
+    // Measure serde + CString conversion (but not FFI return)
+    let start_cstring = Instant::now();
+    for _ in 0..iterations {
+        let serialized = serde_json::to_string(&twitter_data).unwrap();
+        let cstring = CString::new(serialized).unwrap();
+        // Prevent optimization from eliminating the work
+        black_box(&cstring);
+    }
+    let serde_plus_cstring_ns = start_cstring.elapsed().as_nanos() as u64;
+
+    FfiOverheadResult {
+        pure_serde_ns,
+        serde_plus_cstring_ns,
+        iterations,
+        output_size,
+    }
+}
+
+/// Measures FFI overhead for CITM serialization.
+#[no_mangle]
+pub unsafe extern "C" fn measure_citm_ffi_overhead(
+    raw: *mut CitmCatalog,
+    iterations: u64
+) -> FfiOverheadResult {
+    use std::time::Instant;
+
+    let catalog = &*raw;
+    let output_size: u64;
+
+    // Warm-up run
+    let warmup = serde_json::to_string(&catalog).unwrap();
+    output_size = warmup.len() as u64;
+
+    // Measure pure serde_json::to_string() - no CString conversion
+    let start_pure = Instant::now();
+    for _ in 0..iterations {
+        let serialized = serde_json::to_string(&catalog).unwrap();
+        black_box(&serialized);
+    }
+    let pure_serde_ns = start_pure.elapsed().as_nanos() as u64;
+
+    // Measure serde + CString conversion
+    let start_cstring = Instant::now();
+    for _ in 0..iterations {
+        let serialized = serde_json::to_string(&catalog).unwrap();
+        let cstring = CString::new(serialized).unwrap();
+        black_box(&cstring);
+    }
+    let serde_plus_cstring_ns = start_cstring.elapsed().as_nanos() as u64;
+
+    FfiOverheadResult {
+        pure_serde_ns,
+        serde_plus_cstring_ns,
+        iterations,
+        output_size,
+    }
+}

benchmark/static_reflect/serde-benchmark/serde_benchmark.h

@@ -4,6 +4,7 @@
 /* Generated with cbindgen:0.28.0 */
 
 /* Warning, this file is autogenerated by cbindgen. Don't modify this manually. */
+/* Note: FfiOverheadResult and measurement functions added manually */
 
 #include <cstdarg>
 #include <cstdint>
@@ -17,11 +18,25 @@ struct CitmCatalog;
 
 struct TwitterData;
 
+/// Result structure for FFI overhead measurement
+struct FfiOverheadResult {
+    /// Time in nanoseconds for pure serde_json::to_string() (no FFI overhead)
+    uint64_t pure_serde_ns;
+    /// Time in nanoseconds for serde + CString conversion
+    uint64_t serde_plus_cstring_ns;
+    /// Number of iterations performed
+    uint64_t iterations;
+    /// Output size in bytes (for verification)
+    uint64_t output_size;
+};
+
 extern "C" {
 
 TwitterData *twitter_from_str(const char *raw_input, size_t raw_input_length);
 
-const char *str_from_twitter(TwitterData *raw);
+void set_twitter_data(TwitterData *raw);
+
+size_t serialize_twitter_to_string();
 
 void free_twitter(TwitterData *raw);
 
@@ -30,14 +45,22 @@ void free_string(const char *ptr);
 /// Creates a CitmCatalog from a JSON string (UTF-8 encoded).
 CitmCatalog *citm_from_str(const char *raw_input, uintptr_t raw_input_length);
 
-/// Serializes a CitmCatalog into a JSON string (UTF-8).
-char *str_from_citm(CitmCatalog *raw_catalog);
+void set_citm_data(CitmCatalog *raw);
+
+size_t serialize_citm_to_string();
 
 /// Frees the CitmCatalog pointer.
 void free_citm(CitmCatalog *raw_catalog);
 
 void free_str(char *ptr);
 
+/// Measures FFI overhead for Twitter serialization.
+/// Performs `iterations` serializations entirely in Rust and returns timing data.
+FfiOverheadResult measure_twitter_ffi_overhead(TwitterData *raw, uint64_t iterations);
+
+/// Measures FFI overhead for CITM serialization.
+FfiOverheadResult measure_citm_ffi_overhead(CitmCatalog *raw, uint64_t iterations);
+
 }  // extern "C"
 
 }  // namespace serde_benchmark

benchmark/static_reflect/serde-benchmark/src/main.rs

@@ -0,0 +1,31 @@
+use std::fs;
+
+// Include the lib.rs content directly
+include!("../lib.rs");
+
+fn main() {
+    // Read the Twitter JSON file
+    let json_str = fs::read_to_string("/Users/random_person/Desktop/simdjson/build/jsonexamples/twitter.json")
+        .expect("Failed to read file");
+
+    // Parse it
+    let data: TwitterData = serde_json::from_str(&json_str)
+        .expect("Failed to parse JSON");
+
+    // Serialize it back
+    let output = serde_json::to_string(&data)
+        .expect("Failed to serialize");
+
+    // Write to file for comparison
+    fs::write("rust_output.json", &output)
+        .expect("Failed to write output");
+
+    println!("Output size: {} bytes", output.len());
+    println!("Written to rust_output.json");
+
+    // Also write pretty version for easier inspection
+    let pretty = serde_json::to_string_pretty(&data)
+        .expect("Failed to serialize pretty");
+    fs::write("rust_output_pretty.json", &pretty)
+        .expect("Failed to write pretty output");
+}

benchmark/static_reflect/serde-benchmark/src/test_output.rs

@@ -0,0 +1,36 @@
+use std::fs;
+
+// Import from the parent lib.rs
+include!("../lib.rs");
+
+fn main() {
+    // Read the Twitter JSON file
+    let json_str = fs::read_to_string("/Users/random_person/Desktop/simdjson/build/jsonexamples/twitter.json")
+        .expect("Failed to read file");
+
+    // Parse it
+    let data: TwitterData = serde_json::from_str(&json_str)
+        .expect("Failed to parse JSON");
+
+    // Serialize it back (compact)
+    let output = serde_json::to_vec(&data)
+        .expect("Failed to serialize");
+    
+    let output_str = String::from_utf8(output.clone()).unwrap();
+
+    // Write to file for comparison
+    fs::write("rust_output_test.json", &output)
+        .expect("Failed to write output");
+
+    println!("Output size: {} bytes", output.len());
+    
+    // Count statuses
+    println!("Number of statuses: {}", data.statuses.len());
+    
+    // Check what fields are in the first status
+    if let Some(first) = data.statuses.first() {
+        // Let's serialize just the first status to see what fields are included
+        let first_json = serde_json::to_string_pretty(first).unwrap();
+        println!("First status (pretty):\n{}", first_json);
+    }
+}

benchmark/static_reflect/twitter_benchmark/CMakeLists.txt

@@ -1,14 +1,32 @@
 
 # Add executable targets
 add_executable(benchmark_serialization_twitter benchmark_serialization_twitter.cpp)
+add_executable(benchmark_parsing_twitter benchmark_parsing_twitter.cpp)
 
  if(TARGET serde-benchmark)
     message(STATUS "serde-benchmark target was created. Linking benchmarks and serde-benchmark.")
     target_link_libraries(benchmark_serialization_twitter PRIVATE serde-benchmark)
+    target_link_libraries(benchmark_parsing_twitter PRIVATE serde-benchmark)
     target_compile_definitions(benchmark_serialization_twitter PRIVATE SIMDJSON_RUST_VERSION="${Rust_VERSION}")
+    target_compile_definitions(benchmark_parsing_twitter PRIVATE SIMDJSON_RUST_VERSION="${Rust_VERSION}")
 endif()
 target_link_libraries(benchmark_serialization_twitter PRIVATE simdjson::simdjson nlohmann_json)
 target_link_libraries(benchmark_serialization_twitter PRIVATE reflectcpp)
 target_compile_definitions(benchmark_serialization_twitter PRIVATE SIMDJSON_BENCH_CPP_REFLECT=1)
 
-target_compile_definitions(benchmark_serialization_twitter PRIVATE JSON_FILE="${EXAMPLE_JSON}")
+target_link_libraries(benchmark_parsing_twitter PRIVATE simdjson::simdjson nlohmann_json)
+
+if(TARGET rapidjson)
+    target_link_libraries(benchmark_parsing_twitter PRIVATE rapidjson)
+    target_compile_definitions(benchmark_parsing_twitter PRIVATE SIMDJSON_COMPETITION_RAPIDJSON)
+endif()
+
+if(TARGET yyjson)
+    target_link_libraries(benchmark_parsing_twitter PRIVATE yyjson)
+    target_compile_definitions(benchmark_parsing_twitter PRIVATE SIMDJSON_COMPETITION_YYJSON)
+    target_link_libraries(benchmark_serialization_twitter PRIVATE yyjson)
+    target_compile_definitions(benchmark_serialization_twitter PRIVATE SIMDJSON_COMPETITION_YYJSON)
+endif()
+
+target_compile_definitions(benchmark_serialization_twitter PRIVATE JSON_FILE="${EXAMPLE_JSON}")
+target_compile_definitions(benchmark_parsing_twitter PRIVATE JSON_FILE="${EXAMPLE_JSON}")

benchmark/static_reflect/twitter_benchmark/benchmark_parsing_twitter.cpp

@@ -0,0 +1,232 @@
+#include <cassert>
+#include <cstdlib>
+#include <ctime>
+#include <format>
+#include <fstream>
+#include <iostream>
+#include <nlohmann/json.hpp>
+#include <simdjson.h>
+#include <string>
+#include "twitter_data.h"
+#include "nlohmann_twitter_data.h"
+#include "../benchmark_utils/benchmark_helper.h"
+#ifdef SIMDJSON_COMPETITION_RAPIDJSON
+#include "rapidjson_twitter_data.h"
+#endif
+#ifdef SIMDJSON_COMPETITION_YYJSON
+#include "yyjson_twitter_data.h"
+#endif
+
+#ifdef SIMDJSON_RUST_VERSION
+#include "../serde-benchmark/serde_benchmark.h"
+
+void bench_rust_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_rust_parsing",
+               bench([&json_str, &result]() {
+                 serde_benchmark::TwitterData *td = serde_benchmark::twitter_from_str(json_str.c_str(), json_str.size());
+                 result = (td != nullptr);
+                 if (td) {
+                   serde_benchmark::free_twitter(td);
+                 }
+                 if (!result) {
+                   printf("parse error\n");
+                 }
+               }));
+}
+#endif
+
+// OPTIMIZED VERSION: Reuses parser across iterations
+template <class T>
+void bench_simdjson_static_reflection_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  // Pre-allocate padded buffer outside the benchmark loop
+  simdjson::padded_string padded = simdjson::padded_string(json_str);
+
+  // CRITICAL: Create parser OUTSIDE the loop for reuse
+  simdjson::ondemand::parser parser;
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_simdjson_static_reflection_parsing",
+               bench([&padded, &result, &parser]() {
+                 // Reuse the same parser instance
+                 simdjson::ondemand::document doc;
+                 if(parser.iterate(padded).get(doc)) {
+                   result = false;
+                   return;
+                 }
+                 T my_struct;
+                 if(doc.get<T>().get(my_struct)) {
+                   result = false;
+                 }
+                 if (!result) {
+                   printf("parse error\n");
+                 }
+               }));
+}
+
+#if SIMDJSON_STATIC_REFLECTION
+template <class T>
+void bench_simdjson_from_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  // Pre-allocate padded buffer outside the benchmark loop
+  simdjson::padded_string padded = simdjson::padded_string(json_str);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_simdjson_from_parsing",
+               bench([&padded, &result]() {
+                 T my_struct;
+                 auto err = simdjson::from(padded).get(my_struct);
+                  if (err) {
+                    result = false;
+                    printf("parse error: %s\n", simdjson::error_message(err));
+                    return;
+                  }
+               }));
+}
+#endif
+
+ void bench_nlohmann_parsing(const std::string &json_str) {
+   size_t input_volume = json_str.size();
+   printf("# input volume: %zu bytes\n", input_volume);
+
+   volatile bool result = true;
+   pretty_print(1, input_volume, "bench_nlohmann_parsing",
+                bench([&json_str, &result]() {
+                  try {
+                    TwitterData data = nlohmann_deserialize(json_str);
+                    result = true;
+                  } catch (...) {
+                    result = false;
+                    printf("parse error\n");
+                  }
+                }));
+}
+
+#ifdef SIMDJSON_COMPETITION_RAPIDJSON
+void bench_rapidjson_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_rapidjson_parsing",
+               bench([&json_str, &result]() {
+                 try {
+                   TwitterData data = rapidjson_deserialize(json_str);
+                   result = true;
+                 } catch (...) {
+                   result = false;
+                   printf("parse error\n");
+                 }
+               }));
+}
+#endif
+
+#ifdef SIMDJSON_COMPETITION_YYJSON
+void bench_yyjson_parsing(const std::string &json_str) {
+  size_t input_volume = json_str.size();
+  printf("# input volume: %zu bytes\n", input_volume);
+
+  volatile bool result = true;
+  pretty_print(1, input_volume, "bench_yyjson_parsing",
+               bench([&json_str, &result]() {
+                 try {
+                   TwitterData data = yyjson_deserialize(json_str);
+                   result = true;
+                 } catch (...) {
+                   result = false;
+                   printf("parse error\n");
+                 }
+               }));
+}
+#endif
+
+std::string read_file(std::string filename) {
+  printf("# Reading file %s\n", filename.c_str());
+  constexpr size_t read_size = 4096;
+  auto stream = std::ifstream(filename.c_str());
+  stream.exceptions(std::ios_base::badbit);
+  std::string out;
+  std::string buf(read_size, '\0');
+  while (stream.read(&buf[0], read_size)) {
+    out.append(buf, 0, size_t(stream.gcount()));
+  }
+  out.append(buf, 0, size_t(stream.gcount()));
+  return out;
+}
+
+// Function to check if benchmark name matches any of the comma-separated filters
+bool matches_filter(const std::string& benchmark_name, const std::string& filter) {
+  if (filter.empty()) return true;
+
+  // Split filter by comma
+  size_t start = 0;
+  size_t end = filter.find(',');
+  while (end != std::string::npos) {
+    std::string token = filter.substr(start, end - start);
+    if (benchmark_name.find(token) != std::string::npos) {
+      return true;
+    }
+    start = end + 1;
+    end = filter.find(',', start);
+  }
+  // Check last token
+  std::string token = filter.substr(start);
+  return benchmark_name.find(token) != std::string::npos;
+}
+
+int main(int argc, char* argv[]) {
+  std::string filter;
+
+  // Parse command-line arguments
+  for (int i = 1; i < argc; ++i) {
+      if (strcmp(argv[i], "-f") == 0 || strcmp(argv[i], "--filter") == 0) {
+          if (i + 1 < argc) {
+              filter = argv[++i];
+          } else {
+              std::cerr << "Error: -f/--filter requires an argument" << std::endl;
+              return EXIT_FAILURE;
+          }
+      }
+  }
+
+  // Load the JSON data
+  std::string json_str = read_file(JSON_FILE);
+
+  // Benchmarking the parsing
+  if (matches_filter("nlohmann", filter)) {
+    bench_nlohmann_parsing(json_str);
+  }
+#ifdef SIMDJSON_COMPETITION_RAPIDJSON
+  if (matches_filter("rapidjson", filter)) {
+    bench_rapidjson_parsing(json_str);
+  }
+#endif
+#ifdef SIMDJSON_COMPETITION_YYJSON
+  if (matches_filter("yyjson", filter)) {
+    bench_yyjson_parsing(json_str);
+  }
+#endif
+  if (matches_filter("simdjson_static_reflection", filter)) {
+    bench_simdjson_static_reflection_parsing<TwitterData>(json_str);
+  }
+#if SIMDJSON_STATIC_REFLECTION
+  if (matches_filter("simdjson_from", filter)) {
+    bench_simdjson_from_parsing<TwitterData>(json_str);
+  }
+#endif
+#ifdef SIMDJSON_RUST_VERSION
+  if (matches_filter("rust", filter)) {
+    printf("# Note: Rust/Serde parsing test\n");
+    bench_rust_parsing(json_str);
+  }
+#endif
+  return EXIT_SUCCESS;
+}

benchmark/static_reflect/twitter_benchmark/benchmark_serialization_twitter.cpp

@@ -1,4 +1,5 @@
 #include <cassert>
+#include <chrono>
 #include <cstdlib>
 #include <ctime>
 #include <format>
@@ -10,6 +11,9 @@
 #include "twitter_data.h"
 #include "nlohmann_twitter_data.h"
 #include "../benchmark_utils/benchmark_helper.h"
+#ifdef SIMDJSON_COMPETITION_YYJSON
+#include "yyjson_twitter_data.h"
+#endif
 #if SIMDJSON_BENCH_CPP_REFLECT
 #include <rfl.hpp>
 #include <rfl/json.hpp>
@@ -35,19 +39,49 @@ void bench_reflect_cpp(TwitterData &data) {
 
 
 void bench_rust(serde_benchmark::TwitterData *data) {
-  const char * output = serde_benchmark::str_from_twitter(data);
-  size_t output_volume = strlen(output);
+  serde_benchmark::set_twitter_data(data);
+  size_t output_volume = serde_benchmark::serialize_twitter_to_string();
   printf("# output volume: %zu bytes\n", output_volume);
+
   volatile size_t measured_volume = 0;
   pretty_print(1, output_volume, "bench_rust",
-               bench([&data, &measured_volume, &output_volume]() {
-                 const char * output = serde_benchmark::str_from_twitter(data);
-                 serde_benchmark::free_string(output);
+               bench([&measured_volume, &output_volume]() {
+                 measured_volume = serde_benchmark::serialize_twitter_to_string();
                }));
 }
 #endif
 
+// Fair allocation variant: allocates fresh buffer each iteration (matches other libraries)
 template <class T> void bench_simdjson_static_reflection(T &data) {
+  // First run to determine expected size
+  simdjson::builder::string_builder sb_init;
+  simdjson::builder::append(sb_init, data);
+  std::string_view p_init;
+  if(sb_init.view().get(p_init)) {
+    std::cerr << "Error!" << std::endl;
+  }
+  size_t output_volume = p_init.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_static_reflection",
+               bench([&data, &measured_volume, &output_volume]() {
+                 // Fresh allocation each iteration - fair comparison
+                 simdjson::builder::string_builder sb;
+                 simdjson::builder::append(sb, data);
+                 std::string_view p;
+                 if(sb.view().get(p)) {
+                   std::cerr << "Error!" << std::endl;
+                 }
+                 measured_volume = sb.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+
+// Optimized variant: reuses buffer across iterations (shows API potential)
+template <class T> void bench_simdjson_static_reflection_reuse(T &data) {
   simdjson::builder::string_builder sb;
   simdjson::builder::append(sb, data);
   std::string_view p;
@@ -59,7 +93,7 @@ template <class T> void bench_simdjson_static_reflection(T &data) {
   printf("# output volume: %zu bytes\n", output_volume);
 
   volatile size_t measured_volume = 0;
-  pretty_print(sizeof(data), output_volume, "bench_simdjson_static_reflection",
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_reuse_buffer",
                bench([&data, &measured_volume, &output_volume, &sb]() {
                  sb.clear();
                  simdjson::builder::append(sb, data);
@@ -74,6 +108,63 @@ template <class T> void bench_simdjson_static_reflection(T &data) {
                }));
 }
 
+#if SIMDJSON_STATIC_REFLECTION
+// Fair allocation variant: allocates fresh string each iteration
+template <class T> void bench_simdjson_to(T &data) {
+  // First run to determine size
+  std::string output_init;
+  if (simdjson::error_code err = simdjson::builder::to_json(data, output_init); err) {
+    std::cerr << "Error in to_json initialization!" << simdjson::error_message(err) << std::endl;
+    return;
+  }
+  size_t output_volume = output_init.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_to",
+               bench([&data, &measured_volume, &output_volume]() {
+                 // Fresh allocation each iteration - fair comparison
+                 std::string output;
+                 if (simdjson::error_code err = simdjson::builder::to_json(data, output); err) {
+                   std::cerr << "Error in to_json!" << simdjson::error_message(err) << std::endl;
+                   return;
+                 }
+                 measured_volume = output.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+
+// Optimized variant: reuses pre-allocated string
+template <class T> void bench_simdjson_to_reuse(T &data) {
+  std::string output;
+  if (simdjson::error_code err = simdjson::builder::to_json(data, output); err) {
+    std::cerr << "Error in to_json initialization!" << simdjson::error_message(err) << std::endl;
+    return;
+  }
+  size_t output_volume = output.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  // Pre-allocate string with sufficient capacity to avoid reallocation
+  output.reserve(output_volume * 2);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(sizeof(data), output_volume, "bench_simdjson_to_reuse",
+               bench([&data, &measured_volume, &output_volume, &output]() {
+                 // Reuse the pre-allocated string - avoids allocation
+                 if (simdjson::error_code err = simdjson::builder::to_json(data, output); err) {
+                   std::cerr << "Error in to_json!" << simdjson::error_message(err) << std::endl;
+                   return;
+                 }
+                 measured_volume = output.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+#endif
+
 void bench_nlohmann(TwitterData &data) {
   std::string output = nlohmann_serialize(data);
   size_t output_volume = output.size();
@@ -90,28 +181,61 @@ void bench_nlohmann(TwitterData &data) {
                }));
 }
 
+#ifdef SIMDJSON_COMPETITION_YYJSON
+void bench_yyjson(TwitterData &data) {
+  std::string output = yyjson_serialize(data);
+  size_t output_volume = output.size();
+  printf("# output volume: %zu bytes\n", output_volume);
+
+  volatile size_t measured_volume = 0;
+  pretty_print(1, output_volume, "bench_yyjson",
+               bench([&data, &measured_volume, &output_volume]() {
+                 std::string output = yyjson_serialize(data);
+                 measured_volume = output.size();
+                 if (measured_volume != output_volume) {
+                   printf("mismatch\n");
+                 }
+               }));
+}
+#endif
+
 size_t WriteCallback(void *contents, size_t size, size_t nmemb, void *userp) {
   ((std::string *)userp)->append((char *)contents, size * nmemb);
   return size * nmemb;
 }
 
-std::string read_file(std::string filename) {
+simdjson::padded_string read_file(std::string filename) {
   printf("# Reading file %s\n", filename.c_str());
   constexpr size_t read_size = 4096;
   auto stream = std::ifstream(filename.c_str());
   stream.exceptions(std::ios_base::badbit);
-  std::string out;
+  simdjson::padded_string_builder builder;
   std::string buf(read_size, '\0');
   while (stream.read(&buf[0], read_size)) {
-    out.append(buf, 0, size_t(stream.gcount()));
+    builder.append(buf.data(), size_t(stream.gcount()));
   }
-  out.append(buf, 0, size_t(stream.gcount()));
-  return out;
+  builder.append(buf.data(), size_t(stream.gcount()));
+  return builder.convert();
 }
 
-// Function to check if benchmark name contains filter substring
+// Function to check if benchmark name matches any of the comma-separated filters
 bool matches_filter(const std::string& benchmark_name, const std::string& filter) {
-  return filter.empty() || benchmark_name.find(filter) != std::string::npos;
+  if (filter.empty()) return true;
+
+  // Split filter by comma
+  size_t start = 0;
+  size_t end = filter.find(',');
+  while (end != std::string::npos) {
+    std::string token = filter.substr(start, end - start);
+    if (benchmark_name.find(token) != std::string::npos) {
+      return true;
+    }
+    start = end + 1;
+    end = filter.find(',', start);
+  }
+  // Check last token
+  std::string token = filter.substr(start);
+  return benchmark_name.find(token) != std::string::npos;
 }
 
 int main(int argc, char* argv[]) {
@@ -129,12 +253,12 @@ int main(int argc, char* argv[]) {
       }
   }
   // Testing correctness of round-trip (serialization + deserialization)
-  std::string json_str = read_file(JSON_FILE);
+  simdjson::padded_string json_str = read_file(JSON_FILE);
 
   // Loading up the data into a structure.
   simdjson::ondemand::parser parser;
   simdjson::ondemand::document doc;
-  if(parser.iterate(simdjson::pad(json_str)).get(doc)) {
+  if(parser.iterate(json_str).get(doc)) {
     std::cerr << "Error loading the document!" << std::endl;
     return EXIT_FAILURE;
   }
@@ -145,18 +269,41 @@ int main(int argc, char* argv[]) {
   }
 
   // Benchmarking the serialization
+  // Note: simdjson benchmarks include both "fair" (fresh allocation) and "reuse" (buffer reuse) variants
+  // The "fair" variants allocate fresh memory each iteration, matching other libraries' behavior
+  // The "reuse" variants demonstrate the API's potential when buffer reuse is possible
+
   if (matches_filter("nlohmann", filter)) {
     bench_nlohmann(my_struct);
   }
+#ifdef SIMDJSON_COMPETITION_YYJSON
+  if (matches_filter("yyjson", filter)) {
+    bench_yyjson(my_struct);
+  }
+#endif
   if (matches_filter("simdjson_static_reflection", filter)) {
     bench_simdjson_static_reflection(my_struct);
   }
+  if (matches_filter("simdjson_reuse", filter)) {
+    bench_simdjson_static_reflection_reuse(my_struct);
+  }
+#if SIMDJSON_STATIC_REFLECTION
+  if (matches_filter("simdjson_to", filter)) {
+    bench_simdjson_to(my_struct);
+  }
+  if (matches_filter("simdjson_to_reuse", filter)) {
+    bench_simdjson_to_reuse(my_struct);
+  }
+#endif
 #ifdef SIMDJSON_RUST_VERSION
   if (matches_filter("rust", filter)) {
-    printf("# WARNING: The Rust benchmark may not be directly comparable since it does not use an equivalent data structure.\n");
-    serde_benchmark::TwitterData * td = serde_benchmark::twitter_from_str(json_str.c_str(), json_str.size());
-    bench_rust(td);
-    serde_benchmark::free_twitter(td);
+    serde_benchmark::TwitterData * td = serde_benchmark::twitter_from_str(json_str.data(), json_str.size());
+    if (td == nullptr) {
+      printf("# Failed to parse Twitter data for Rust benchmark\n");
+    } else {
+      bench_rust(td);
+      serde_benchmark::free_twitter(td);
+    }
   }
 #endif
 #if SIMDJSON_BENCH_CPP_REFLECT

benchmark/static_reflect/twitter_benchmark/nlohmann_twitter_data.h

@@ -4,6 +4,7 @@
 #include "twitter_data.h"
 #include <nlohmann/json.hpp>
 
+// Serialization functions for nlohmann
 void to_json(nlohmann::json &j, const User &u) {
   j = nlohmann::json{{"id", u.id},
                      {"name", u.name},
@@ -16,101 +17,54 @@ void to_json(nlohmann::json &j, const User &u) {
                      {"statuses_count", u.statuses_count}};
 }
 
-void to_json(nlohmann::json &j, const Hashtag &h) {
-  j = nlohmann::json{{"text", h.text},
-                     {"indices_start", h.indices_start},
-                     {"indices_end", h.indices_end}};
-}
-
-void to_json(nlohmann::json &j, const Url &u) {
-  j = nlohmann::json{{"url", u.url},
-                     {"expanded_url", u.expanded_url},
-                     {"display_url", u.display_url},
-                     {"indices_start", u.indices_start},
-                     {"indices_end", u.indices_end}};
-}
-
-void to_json(nlohmann::json &j, const UserMention &um) {
-  j = nlohmann::json{{"id", um.id},
-                     {"name", um.name},
-                     {"screen_name", um.screen_name},
-                     {"indices_start", um.indices_start},
-                     {"indices_end", um.indices_end}};
-}
-
-void to_json(nlohmann::json &j, const Entities &e) {
-  j = nlohmann::json{{"hashtags", e.hashtags},
-                     {"urls", e.urls},
-                     {"user_mentions", e.user_mentions}};
-}
-
 void to_json(nlohmann::json &j, const Status &s) {
   j = nlohmann::json{{"created_at", s.created_at},
                      {"id", s.id},
                      {"text", s.text},
                      {"user", s.user},
-                     {"entities", s.entities},
                      {"retweet_count", s.retweet_count},
-                     {"favorite_count", s.favorite_count},
-                     {"favorited", s.favorited},
-                     {"retweeted", s.retweeted}};
-}
-
-
-std::string nlohmann_serialize(const std::vector<Hashtag>& v) {
-  nlohmann::json a = nlohmann::json::array();
-  for(const Hashtag & h : v) {
-    a.push_back(nlohmann::json{{"text", h.text},
-                     {"indices_start", h.indices_start},
-                     {"indices_end", h.indices_end}});
-  }
-  return a.dump();
-}
-std::string nlohmann_serialize(const std::vector<Url>& v) {
-  nlohmann::json a = nlohmann::json::array();
-  for(const Url & u : v) {
-    a.push_back(nlohmann::json{{"url", u.url},
-                     {"expanded_url", u.expanded_url},
-                     {"display_url", u.display_url},
-                     {"indices_start", u.indices_start},
-                     {"indices_end", u.indices_end}});
-  }
-  return a.dump();
-}
-std::string nlohmann_serialize(const std::vector<UserMention>& v) {
-  nlohmann::json a = nlohmann::json::array();
-  for(const UserMention & um : v) {
-    a.push_back(nlohmann::json{{"id", um.id},
-                     {"name", um.name},
-                     {"screen_name", um.screen_name},
-                     {"indices_start", um.indices_start},
-                     {"indices_end", um.indices_end}});
-  }
-  return a.dump();
-}
-
-std::string nlohmann_serialize(const std::vector<Status>& v) {
-  nlohmann::json a = nlohmann::json::array();
-  for(const Status & s : v) {
-    a.push_back(nlohmann::json{{"created_at", s.created_at},
-                     {"id", s.id},
-                     {"text", s.text},
-                     {"user", s.user},
-                     {"entities", s.entities},
-                     {"retweet_count", s.retweet_count},
-                     {"favorite_count", s.favorite_count},
-                     {"favorited", s.favorited},
-                     {"retweeted", s.retweeted}});
-  }
-  return a.dump();
+                     {"favorite_count", s.favorite_count}};
 }
 
 void to_json(nlohmann::json &j, const TwitterData &t) {
   j = nlohmann::json{{"statuses", t.statuses}};
 }
 
+// Deserialization functions for nlohmann
+void from_json(const nlohmann::json &j, User &u) {
+  j.at("id").get_to(u.id);
+  j.at("name").get_to(u.name);
+  j.at("screen_name").get_to(u.screen_name);
+  j.at("location").get_to(u.location);
+  j.at("description").get_to(u.description);
+  j.at("verified").get_to(u.verified);
+  j.at("followers_count").get_to(u.followers_count);
+  j.at("friends_count").get_to(u.friends_count);
+  j.at("statuses_count").get_to(u.statuses_count);
+}
+
+void from_json(const nlohmann::json &j, Status &s) {
+  j.at("created_at").get_to(s.created_at);
+  j.at("id").get_to(s.id);
+  j.at("text").get_to(s.text);
+  j.at("user").get_to(s.user);
+  j.at("retweet_count").get_to(s.retweet_count);
+  j.at("favorite_count").get_to(s.favorite_count);
+}
+
+void from_json(const nlohmann::json &j, TwitterData &t) {
+  j.at("statuses").get_to(t.statuses);
+}
+
+// Helper functions for benchmarking
 std::string nlohmann_serialize(const TwitterData &data) {
-  return nlohmann_serialize(data.statuses);
+  nlohmann::json j = data;
+  return j.dump();
+}
+
+TwitterData nlohmann_deserialize(const std::string &json_str) {
+  nlohmann::json j = nlohmann::json::parse(json_str);
+  return j.get<TwitterData>();
 }
 
 #endif // NLOHMANN_TWITTER_DATA_H

benchmark/static_reflect/twitter_benchmark/rapidjson_twitter_data.h

@@ -0,0 +1,142 @@
+#ifndef RAPIDJSON_TWITTER_DATA_H
+#define RAPIDJSON_TWITTER_DATA_H
+
+#include "twitter_data.h"
+#include <rapidjson/document.h>
+#include <rapidjson/writer.h>
+#include <rapidjson/stringbuffer.h>
+#include <rapidjson/error/en.h>
+
+using namespace rapidjson;
+
+// RapidJSON deserialization for simplified Twitter data
+TwitterData rapidjson_deserialize(const std::string& json_str) {
+    Document doc;
+    doc.Parse(json_str.c_str());
+
+    if (doc.HasParseError()) {
+        throw std::runtime_error("RapidJSON parse error");
+    }
+
+    TwitterData data;
+
+    if (!doc.HasMember("statuses") || !doc["statuses"].IsArray()) {
+        return data;
+    }
+
+    const Value& statuses = doc["statuses"];
+    data.statuses.reserve(statuses.Size());
+
+    for (SizeType i = 0; i < statuses.Size(); i++) {
+        const Value& status_json = statuses[i];
+        Status status;
+
+        // Parse status fields
+        if (status_json.HasMember("created_at") && status_json["created_at"].IsString())
+            status.created_at = status_json["created_at"].GetString();
+        if (status_json.HasMember("id") && status_json["id"].IsUint64())
+            status.id = status_json["id"].GetUint64();
+        if (status_json.HasMember("text") && status_json["text"].IsString())
+            status.text = status_json["text"].GetString();
+        if (status_json.HasMember("retweet_count") && status_json["retweet_count"].IsUint64())
+            status.retweet_count = status_json["retweet_count"].GetUint64();
+        if (status_json.HasMember("favorite_count") && status_json["favorite_count"].IsUint64())
+            status.favorite_count = status_json["favorite_count"].GetUint64();
+
+        // Parse user
+        if (status_json.HasMember("user") && status_json["user"].IsObject()) {
+            const Value& user_json = status_json["user"];
+            User user;
+
+            if (user_json.HasMember("id") && user_json["id"].IsUint64())
+                user.id = user_json["id"].GetUint64();
+            if (user_json.HasMember("name") && user_json["name"].IsString())
+                user.name = user_json["name"].GetString();
+            if (user_json.HasMember("screen_name") && user_json["screen_name"].IsString())
+                user.screen_name = user_json["screen_name"].GetString();
+            if (user_json.HasMember("location") && user_json["location"].IsString())
+                user.location = user_json["location"].GetString();
+            if (user_json.HasMember("description") && user_json["description"].IsString())
+                user.description = user_json["description"].GetString();
+            if (user_json.HasMember("verified") && user_json["verified"].IsBool())
+                user.verified = user_json["verified"].GetBool();
+            if (user_json.HasMember("followers_count") && user_json["followers_count"].IsUint64())
+                user.followers_count = user_json["followers_count"].GetUint64();
+            if (user_json.HasMember("friends_count") && user_json["friends_count"].IsUint64())
+                user.friends_count = user_json["friends_count"].GetUint64();
+            if (user_json.HasMember("statuses_count") && user_json["statuses_count"].IsUint64())
+                user.statuses_count = user_json["statuses_count"].GetUint64();
+
+            status.user = user;
+        }
+
+        data.statuses.push_back(status);
+    }
+
+    return data;
+}
+
+// RapidJSON serialization for simplified Twitter data
+std::string rapidjson_serialize(const TwitterData& data) {
+    Document doc;
+    doc.SetObject();
+    Document::AllocatorType& allocator = doc.GetAllocator();
+
+    Value statuses_array(kArrayType);
+
+    for (const auto& status : data.statuses) {
+        Value status_obj(kObjectType);
+
+        Value created_at;
+        created_at.SetString(status.created_at.c_str(), allocator);
+        status_obj.AddMember("created_at", created_at, allocator);
+
+        status_obj.AddMember("id", status.id, allocator);
+
+        Value text;
+        text.SetString(status.text.c_str(), allocator);
+        status_obj.AddMember("text", text, allocator);
+
+        // Add user
+        Value user_obj(kObjectType);
+        user_obj.AddMember("id", status.user.id, allocator);
+
+        Value name;
+        name.SetString(status.user.name.c_str(), allocator);
+        user_obj.AddMember("name", name, allocator);
+
+        Value screen_name;
+        screen_name.SetString(status.user.screen_name.c_str(), allocator);
+        user_obj.AddMember("screen_name", screen_name, allocator);
+
+        Value location;
+        location.SetString(status.user.location.c_str(), allocator);
+        user_obj.AddMember("location", location, allocator);
+
+        Value description;
+        description.SetString(status.user.description.c_str(), allocator);
+        user_obj.AddMember("description", description, allocator);
+
+        user_obj.AddMember("verified", status.user.verified, allocator);
+        user_obj.AddMember("followers_count", status.user.followers_count, allocator);
+        user_obj.AddMember("friends_count", status.user.friends_count, allocator);
+        user_obj.AddMember("statuses_count", status.user.statuses_count, allocator);
+
+        status_obj.AddMember("user", user_obj, allocator);
+
+        status_obj.AddMember("retweet_count", status.retweet_count, allocator);
+        status_obj.AddMember("favorite_count", status.favorite_count, allocator);
+
+        statuses_array.PushBack(status_obj, allocator);
+    }
+
+    doc.AddMember("statuses", statuses_array, allocator);
+
+    StringBuffer buffer;
+    Writer<StringBuffer> writer(buffer);
+    doc.Accept(writer);
+
+    return buffer.GetString();
+}
+
+#endif // RAPIDJSON_TWITTER_DATA_H

benchmark/static_reflect/twitter_benchmark/twitter_data.h

@@ -4,68 +4,31 @@
 #include <string>
 #include <vector>
 
+// Simplified Twitter structures for benchmarking
+
 struct User {
-  int64_t id;
-  std::string id_str;
+  uint64_t id;
   std::string name;
   std::string screen_name;
   std::string location;
   std::string description;
   bool verified;
-  int64_t followers_count;
-  int64_t friends_count;
-  int64_t statuses_count;
-  bool operator<=>(const User &other) const = default;
-};
-
-struct Hashtag {
-  std::string text;
-  int64_t indices_start;
-  int64_t indices_end;
-  bool operator<=>(const Hashtag &other) const = default;
-};
-
-struct Url {
-  std::string url;
-  std::string expanded_url;
-  std::string display_url;
-  int64_t indices_start;
-  int64_t indices_end;
-  bool operator<=>(const Url &other) const = default;
-};
-
-struct UserMention {
-  int64_t id;
-  std::string name;
-  std::string screen_name;
-  int64_t indices_start;
-  int64_t indices_end;
-  bool operator<=>(const UserMention &other) const = default;
-};
-
-struct Entities {
-  std::vector<Hashtag> hashtags;
-  std::vector<Url> urls;
-  std::vector<UserMention> user_mentions;
-  bool operator==(const Entities &other) const = default;
+  uint64_t followers_count;
+  uint64_t friends_count;
+  uint64_t statuses_count;
 };
 
 struct Status {
   std::string created_at;
-  int64_t id;
+  uint64_t id;
   std::string text;
   User user;
-  Entities entities;
-  int64_t retweet_count;
-  int64_t favorite_count;
-  bool favorited;
-  bool retweeted;
-  bool operator==(const Status &other) const = default;
+  uint64_t retweet_count;
+  uint64_t favorite_count;
 };
 
 struct TwitterData {
   std::vector<Status> statuses;
-  bool operator==(const TwitterData &other) const = default;
 };
 
-#endif
+#endif // TWITTER_DATA_H

benchmark/static_reflect/twitter_benchmark/yyjson_twitter_data.h

@@ -0,0 +1,145 @@
+#ifndef YYJSON_TWITTER_DATA_H
+#define YYJSON_TWITTER_DATA_H
+
+#include "twitter_data.h"
+#include <yyjson.h>
+#include <string>
+#include <stdexcept>
+
+// yyjson deserialization for simplified Twitter data
+TwitterData yyjson_deserialize(const std::string &json_str) {
+    TwitterData data;
+
+    yyjson_doc *doc = yyjson_read(json_str.c_str(), json_str.size(), 0);
+    if (!doc) {
+        throw std::runtime_error("yyjson parse error");
+    }
+
+    yyjson_val *root = yyjson_doc_get_root(doc);
+    if (!root) {
+        yyjson_doc_free(doc);
+        return data;
+    }
+
+    // Get statuses array
+    yyjson_val *statuses_val = yyjson_obj_get(root, "statuses");
+    if (!statuses_val || !yyjson_is_arr(statuses_val)) {
+        yyjson_doc_free(doc);
+        return data;
+    }
+
+    size_t idx, max;
+    yyjson_val *status_val;
+    yyjson_arr_foreach(statuses_val, idx, max, status_val) {
+        Status status;
+
+        // Parse status fields
+        yyjson_val *val;
+
+        val = yyjson_obj_get(status_val, "created_at");
+        if (val && yyjson_is_str(val)) status.created_at = yyjson_get_str(val);
+
+        val = yyjson_obj_get(status_val, "id");
+        if (val && yyjson_is_uint(val)) status.id = yyjson_get_uint(val);
+
+        val = yyjson_obj_get(status_val, "text");
+        if (val && yyjson_is_str(val)) status.text = yyjson_get_str(val);
+
+        val = yyjson_obj_get(status_val, "retweet_count");
+        if (val && yyjson_is_uint(val)) status.retweet_count = yyjson_get_uint(val);
+
+        val = yyjson_obj_get(status_val, "favorite_count");
+        if (val && yyjson_is_uint(val)) status.favorite_count = yyjson_get_uint(val);
+
+        // Parse user
+        yyjson_val *user_val = yyjson_obj_get(status_val, "user");
+        if (user_val && yyjson_is_obj(user_val)) {
+            User user;
+
+            val = yyjson_obj_get(user_val, "id");
+            if (val && yyjson_is_uint(val)) user.id = yyjson_get_uint(val);
+
+            val = yyjson_obj_get(user_val, "name");
+            if (val && yyjson_is_str(val)) user.name = yyjson_get_str(val);
+
+            val = yyjson_obj_get(user_val, "screen_name");
+            if (val && yyjson_is_str(val)) user.screen_name = yyjson_get_str(val);
+
+            val = yyjson_obj_get(user_val, "location");
+            if (val && yyjson_is_str(val)) user.location = yyjson_get_str(val);
+
+            val = yyjson_obj_get(user_val, "description");
+            if (val && yyjson_is_str(val)) user.description = yyjson_get_str(val);
+
+            val = yyjson_obj_get(user_val, "verified");
+            if (val && yyjson_is_bool(val)) user.verified = yyjson_get_bool(val);
+
+            val = yyjson_obj_get(user_val, "followers_count");
+            if (val && yyjson_is_uint(val)) user.followers_count = yyjson_get_uint(val);
+
+            val = yyjson_obj_get(user_val, "friends_count");
+            if (val && yyjson_is_uint(val)) user.friends_count = yyjson_get_uint(val);
+
+            val = yyjson_obj_get(user_val, "statuses_count");
+            if (val && yyjson_is_uint(val)) user.statuses_count = yyjson_get_uint(val);
+
+            status.user = user;
+        }
+
+        data.statuses.push_back(status);
+    }
+
+    yyjson_doc_free(doc);
+    return data;
+}
+
+// yyjson serialization for simplified Twitter data
+std::string yyjson_serialize(const TwitterData &data) {
+    yyjson_mut_doc *doc = yyjson_mut_doc_new(NULL);
+    yyjson_mut_val *root = yyjson_mut_obj(doc);
+    yyjson_mut_doc_set_root(doc, root);
+
+    // Create statuses array
+    yyjson_mut_val *statuses_array = yyjson_mut_arr(doc);
+
+    for (const auto& status : data.statuses) {
+        yyjson_mut_val *status_obj = yyjson_mut_obj(doc);
+
+        // Add status fields
+        yyjson_mut_obj_add_str(doc, status_obj, "created_at", status.created_at.c_str());
+        yyjson_mut_obj_add_uint(doc, status_obj, "id", status.id);
+        yyjson_mut_obj_add_str(doc, status_obj, "text", status.text.c_str());
+
+        // User object
+        yyjson_mut_val *user_obj = yyjson_mut_obj(doc);
+        yyjson_mut_obj_add_uint(doc, user_obj, "id", status.user.id);
+        yyjson_mut_obj_add_str(doc, user_obj, "name", status.user.name.c_str());
+        yyjson_mut_obj_add_str(doc, user_obj, "screen_name", status.user.screen_name.c_str());
+        yyjson_mut_obj_add_str(doc, user_obj, "location", status.user.location.c_str());
+        yyjson_mut_obj_add_str(doc, user_obj, "description", status.user.description.c_str());
+        yyjson_mut_obj_add_bool(doc, user_obj, "verified", status.user.verified);
+        yyjson_mut_obj_add_uint(doc, user_obj, "followers_count", status.user.followers_count);
+        yyjson_mut_obj_add_uint(doc, user_obj, "friends_count", status.user.friends_count);
+        yyjson_mut_obj_add_uint(doc, user_obj, "statuses_count", status.user.statuses_count);
+        yyjson_mut_obj_add_val(doc, status_obj, "user", user_obj);
+
+        // Other fields
+        yyjson_mut_obj_add_uint(doc, status_obj, "retweet_count", status.retweet_count);
+        yyjson_mut_obj_add_uint(doc, status_obj, "favorite_count", status.favorite_count);
+
+        yyjson_mut_arr_append(statuses_array, status_obj);
+    }
+
+    // Add statuses array to root
+    yyjson_mut_obj_add_val(doc, root, "statuses", statuses_array);
+
+    // Write to string
+    char *json_output = yyjson_mut_write(doc, 0, NULL);
+    std::string result(json_output);
+    free(json_output);
+    yyjson_mut_doc_free(doc);
+
+    return result;
+}
+
+#endif // YYJSON_TWITTER_DATA_H

doc/basics.md

@@ -169,8 +169,10 @@ For efficiency reasons, simdjson requires a string with a few bytes (`simdjson::
 at the end, these bytes may be read but their content does not affect the parsing. In practice,
 it means that the JSON inputs should be stored in a memory region with `simdjson::SIMDJSON_PADDING`
 extra bytes at the end. You do not have to set these bytes to specific values though you may
-want to if you want to avoid runtime warnings with some sanitizers. Advanced users may want to
-read the section Free Padding in [our performance notes](performance.md).
+want to if you want to avoid runtime warnings with some sanitizers. We expect the user
+of the library to load the data (from disk or from the network) into a padded buffer. To make
+this easy, we provide the `padded_string::load` function which loads files from disk in a padded buffer.
+[You can similarly fetch a file from a URL to a padded string](https://github.com/simdjson/curltostring) using our `simdjson::padded_string_builder`. Advanced users may want to read the section Free Padding in [our performance notes](performance.md).
 
 The simdjson library offers a tree-like [API](https://en.wikipedia.org/wiki/API), which you can
 access by creating a `ondemand::parser` and calling the `iterate()` method. The iterate method
@@ -354,7 +356,13 @@ the  macro `SIMDJSON_DEVELOPMENT_CHECKS` to 1 prior to including
 the `simdjson.h` header to enable these additional checks: just make sure you remove the
 definition once your code has been tested. When `SIMDJSON_DEVELOPMENT_CHECKS` is set to 1, the
 simdjson library runs additional (expensive) tests on your code to help ensure that you are
-using the library in a safe manner.
+using the library in a safe manner. We add asserts which may halt your program, helping
+you find the bad programming pattern.
+
+When `SIMDJSON_DEVELOPMENT_CHECKS`, some of our data structures contain extra data for
+tracking explicitly potential programming mistakes. Thus you should not relying on the
+size (`sizeof`) of our data structures to be constant: they may change depending on the
+compiler settings.
 
 Once your code has been tested, you can then run it in
 Release mode: under Visual Studio, it means having the `_DEBUG` macro undefined, and, for other
@@ -437,8 +445,8 @@ support for users who avoid exceptions. See [the simdjson error handling documen
 
   If you know the type of the value, you can cast it right there, too! `for (double value : array) { ... }`.
 
-  You may also use explicit iterators: `for(auto i = array.begin(); i != array.end(); i++) {}`. You can check that an array is empty with the condition `auto i = array.begin(); if (i == array.end()) {...}`.
-* **Object Iteration:** You can iterate through an object's fields, as well: `for (auto field : object) { ... }`. You may also use explicit iterators : `for(auto i = object.begin(); i != object.end(); i++) { auto field = *i; .... }`. You can check that an object is empty with the condition `auto i = object.begin(); if (i == object.end()) {...}`.
+  You may also use explicit iterators: `for(auto i = array.begin(); i != array.end(); i++) {}`. You can check that an array is empty with the condition `auto i = array.begin(); if (i == array.end()) {...}`. You should derefence (`*i`) an iterator at most once before incrementing it (`i++`), when compiling in debug mode with development checks, we add asserts to help you identify such a mistake.
+* **Object Iteration:** You can iterate through an object's fields, as well: `for (auto field : object) { ... }`.
   - `field.unescaped_key()` will get you the unescaped key string as a `std::string_view` instance. E.g., the JSON string `"\u00e1"` becomes the Unicode string `á`. Optionally,  you pass `true` as a parameter to the `unescaped_key` method if you want invalid escape sequences to be replaced by a default replacement character (e.g., `\ud800\ud801\ud811`): otherwise bad escape sequences lead to an immediate error.
   - `field.escaped_key()` will get you the key string as  as a `std::string_view` instance, but unlike `unescaped_key()`, the key is not processed, so no unescaping is done. E.g., the JSON string `"\u00e1"` becomes the Unicode string `\u00e1`. We expect that `escaped_key()` is faster than `field.unescaped_key()`.
   - `field.value()` will get you the value, which you can then use all these other methods on.
@@ -451,13 +459,17 @@ support for users who avoid exceptions. See [the simdjson error handling documen
 
   When you are iterating through an object, you are advancing through its keys and values. You should not also access the object or other objects. E.g. within a loop over `myobject`, you should not be accessing `myobject`. The following is an anti-pattern: `for(auto value: myobject) {myobject["mykey"]}`.
 
+  We discourage using the object iterators explicitly: `for(auto i = object.begin(); i != object.end(); i++) { auto field = *i; .... }`. In addition to the usual requirement to check against `end()` prior to dereferencing, you must also always dereference the pointer (`*it`) exactly once before you increment it (`it++`). You must also only deference the iterator once (never more than once). When compiling in
+  debug mode with development checks, we add asserts to help check whether you correctly
+  dereferenced the pointer before incrementing it.
+
   You should never reset an object as you are iterating through it. The following is an anti-pattern: `for(auto value: myobject) {myobject.reset()}`.
 * **Array Index:** Because it is forward-only, you cannot look up an array element by index. Instead,
   you should iterate through the array and keep an index yourself. Exceptionally, if need a single value
   out of the array, you may use an array access (e.g., `array[1]`). You should never reset an array as you are iterating through it. The following is an anti-pattern: `for(auto value: myarray) {myarray.reset()}`.
 * **Field Access:** To get the value of the "foo" field in an object, use `object["foo"]`. This will
   scan through the object looking for the field with the matching string, doing a character-by-character
-  comparison. It may generate the error `simdjson::NO_SUCH_FIELD` if there is no such key in the object, it may throw an exception (see [Error handling](#error-handling)). For efficiency reason, you should avoid looking up the same field repeatedly: e.g., do
+  comparison. It may generate the error `simdjson::NO_SUCH_FIELD` if there is no such key in the object, it may throw an exception (see [Error handling](#error-handling)). The returned value is only valid so long as you do not access another field: normally, you should therefore grab the value right after accessing a key (i.e., convert it to number, string, object, array...). For efficiency reason, you should avoid looking up the same field repeatedly: e.g., do
   not do `object["foo"]` followed by `object["foo"]` with the same `object` instance. Generally, you should not mix and match iterating through an object (`for(auto field : object) {...}`) and key accesses (`object["foo"]`): if you need to iterate through an object after a key access, you need to call `reset()` on the object. Whenever you call `reset()`, you need to keep in mind that though you can iterate over the array repeatedly, values should be consumedonly once (e.g., repeatedly calling `unescaped_key()` on the same  key is forbidden). Keep in mind that On-Demand does not buffer or save the result of the parsing: if you repeatedly access `object["foo"]`, then it must repeatedly seek the key and parse the content. The library does not provide a distinct function to check if a key is present, instead we recommend you attempt to access the key: e.g., by doing `ondemand::value val{}; if (!object["foo"].get(val)) {...}`, you have that `val` contains the requested value inside the if clause.  It is your responsibility as a user to temporarily keep a reference to the value (`auto v = object["foo"]`), or to consume the content and store it in your own data structures. If you consume an
   object twice: `std::string_view(object["foo"]` followed by `std::string_view(object["foo"]` then your code
   is in error. Furthermore, you can only consume one field at a time, on the same object. The

doc/builder.md

@@ -14,6 +14,7 @@ speed and high convenience.
   * [C++26 static reflection](#c--26-static-reflection)
     + [Without `string_buffer` instance](#without--string-buffer--instance)
     + [Without `string_buffer` instance but with explicit error handling](#without--string-buffer--instance-but-with-explicit-error-handling)
+    + [Pretty formatted (fractured JSON)](#pretty-formatted-fractured-json)
 
 Overview: string_builder
 ---------------------------
@@ -332,7 +333,7 @@ pattern:
 
 ### Customization
 
-If you want to serialize a value in a custome way, you can do it with a
+If you want to serialize a value in a custom way, you can do it with a
 `tag_invoke` specialization like the following example which will map
 the year attribute to a string.
 
@@ -363,4 +364,50 @@ void tag_invoke(serialize_tag, builder_type &builder, const Car& car) {
 }
 
 } // namespace simdjson
-```
+```
+
+### Pretty formatted (fractured JSON)
+
+In some instances, you may want your JSON to be more readable. For this pupose, we also
+support the Fractured JSON standard.
+
+```Cpp
+  TableTestData data{
+    {{1, "Alice", true}, {2, "Bob", false}, {3, "Carol", true}, {4, "Dave", false}}
+  };
+
+  fractured_json_options opts;
+  opts.enable_table_format = true;
+  opts.min_table_rows = 3;
+
+  std::string formatted = simdjson::to_fractured_json_string(data, opts);
+```
+
+The result might be as follows.
+
+```json
+{
+    "records": [
+        { "active": true , "id": 1, "name": "Alice" },
+        { "active": false, "id": 2, "name": "Bob" },
+        { "active": true , "id": 3, "name": "Carol" },
+        { "active": false, "id": 4, "name": "Dave" }
+    ]
+}
+```
+
+The `fractured_json_options` struct allows you to customize the formatting behavior. It includes the following options:
+
+- `max_total_line_length` (default: 120): Maximum total characters per line. Content exceeding this will be expanded to multiple lines.
+- `max_inline_length` (default: 80): Maximum length for inlined elements. Simple arrays/objects shorter than this may be rendered inline.
+- `max_inline_complexity` (default: 2): Maximum nesting depth for inline rendering. Elements with complexity exceeding this will be expanded. Complexity 0 = scalar, 1 = flat array/object, 2 = one level of nesting.
+- `max_compact_array_complexity` (default: 1): Maximum complexity for compact array formatting. Arrays with elements of this complexity or less may have multiple items per line.
+- `indent_spaces` (default: 4): Number of spaces per indentation level.
+- `enable_table_format` (default: true): Enable tabular formatting for arrays of similar objects. When enabled, arrays of objects with identical keys are formatted as aligned tables.
+- `min_table_rows` (default: 3): Minimum number of rows to trigger table mode.
+- `table_similarity_threshold` (default: 0.8): Similarity threshold for table detection. Objects must share at least this fraction of keys to be formatted as a table.
+- `enable_compact_multiline` (default: true): Enable compact multiline arrays. When enabled, arrays of simple elements may have multiple items per line.
+- `max_items_per_line` (default: 10): Maximum array items per line in compact mode.
+- `simple_bracket_padding` (default: true): Add space inside brackets for simple containers. When true: `{ "key": "value" }`, when false: `{"key": "value"}`.
+- `colon_padding` (default: true): Add space after colons. When true: `"key": "value"`, when false: `"key":"value"`.
+- `comma_padding` (default: true): Add space after commas in inline content. When true: `[1, 2, 3]`, when false: `[1,2,3]`.

doc/compile_time.md

@@ -128,7 +128,7 @@ Let us consider this example:
 ```
 
 You might want to ensure that the result is an array of persons. You can define your
-expection with concepts like so:
+expectation with concepts like so:
 
 ```cpp
 template <typename T>

doc/dom.md

@@ -62,6 +62,8 @@ auto json = padded_string::load("twitter.json"); // load JSON file 'twitter.json
 dom::element doc = parser.parse(json);
 ```
 
+[You can similarly fetch a file from a URL to a padded string](https://github.com/simdjson/curltostring) using our `simdjson::padded_string_builder`.
+
 (Windows users compiling with C++17 or better may use `wchar_t` strings to support non-ASCII
 filenames: `padded_string::load(L"twitter.json")`.)
 

doc/performance.md

@@ -297,4 +297,62 @@ int main() {
   }
   return EXIT_SUCCESS;
 }
+```
+
+Further, whenever you allocate N bytes, memory allocators tend to allocate more memory, without you necessarily knowing about it. Under linux, you can use the `malloc_usable_size` function to see how much memory was actually allocated.
+Under an Apple plateform, you can  `malloc_size`. The following program illustrates the usage.
+
+```cpp
+#include <iostream>
+#include <cstddef>
+#include <memory>
+#include <cstdlib>
+#ifdef __APPLE__
+#include <malloc/malloc.h>  // for malloc_size on macOS
+#endif
+#ifdef __linux__
+#include <malloc.h> // for malloc_usable_size on Linux
+#endif
+size_t get_usable_size(void* ptr) {
+#ifdef __linux__
+    return malloc_usable_size(ptr);
+#elif defined(__APPLE__)
+    return malloc_size(ptr);
+#else
+    return 0;  // Unsupported platform
+#endif
+}
+
+int main() {
+    std::cout << "Demonstrating allocation overhead and rounding with operator new\n\n";
+
+#ifdef __linux__
+    std::cout << "Platform: Linux\n";
+#elif defined(__APPLE__)
+    std::cout << "Platform: macOS (using malloc_size)\n";
+#else
+    std::cout << "Platform: Other/unsupported (usable size will show 0)\n";
+#endif
+
+    std::cout << "Requested size | Actual usable size\n";
+    std::cout << "---------------|-------------------\n";
+    size_t total_requested = 0;
+    size_t total_usable = 0;
+    for (size_t requested = 1; requested <= 4096; requested++) {
+        total_requested += requested;
+        std::unique_ptr<char[]> ptr(new char[requested]);  // Allocate
+        size_t usable = get_usable_size(ptr.get());  // Get usable size
+        total_usable += usable;
+
+        std::cout << requested << "\t       | " << usable << "\n";
+    }
+    std::cout << "---------------|-------------------\n";
+    std::cout << "Total requested: " << total_requested << " bytes\n";
+    std::cout << "Total usable:    " << total_usable << " bytes\n";
+    std::cout << "Total overhead:  " << (total_usable - total_requested) << " bytes\n";
+    std::cout << "Percentage overhead: "
+              << ((total_usable - total_requested) * 100.0 / total_requested) << " %\n";
+
+    return EXIT_SUCCESS;
+}
 ```

fuzz/ossfuzz.sh

@@ -35,7 +35,7 @@ cmake .. \
 -DSIMDJSON_DISABLE_DEPRECATED_API=On \
 -DSIMDJSON_FUZZ_LDFLAGS=$LIB_FUZZING_ENGINE
 
-cmake --build . --target all_fuzzers
+cmake --build . --target all_fuzzers all_tests
 
 cp fuzz/fuzz_* $OUT
 

include/simdjson.h

@@ -52,6 +52,7 @@
 #include "simdjson/padded_string_view-inl.h"
 
 #include "simdjson/dom.h"
+#include "simdjson/builder.h"
 #include "simdjson/ondemand.h"
 #include "simdjson/convert.h"
 #include "simdjson/convert-inl.h"

include/simdjson/arm64/builder.h

@@ -0,0 +1,8 @@
+#ifndef SIMDJSON_ARM64_BUILDER_H
+#define SIMDJSON_ARM64_BUILDER_H
+
+#include "simdjson/arm64/begin.h"
+#include "simdjson/generic/builder/amalgamated.h"
+#include "simdjson/arm64/end.h"
+
+#endif // SIMDJSON_ARM64_BUILDER_H

include/simdjson/arm64/simd.h

@@ -428,6 +428,7 @@ namespace {
     static constexpr int NUM_CHUNKS = 64 / sizeof(simd8<T>);
     static_assert(NUM_CHUNKS == 4, "ARM kernel should use four registers per 64-byte block.");
     const simd8<T> chunks[NUM_CHUNKS];
+    template<int idx> simd8<uint8_t> get() const { return idx < NUM_CHUNKS ? chunks[idx] : simd8<T>(); }
 
     simd8x64(const simd8x64<T>& o) = delete; // no copy allowed
     simd8x64<T>& operator=(const simd8<T>& other) = delete; // no assignment allowed

include/simdjson/builder.h

@@ -0,0 +1,14 @@
+#ifndef SIMDJSON_BUILDER_H
+#define SIMDJSON_BUILDER_H
+
+#include "simdjson/builtin/builder.h"
+
+namespace simdjson {
+  /**
+   * @copydoc simdjson::builtin::builder
+   */
+  namespace builder = builtin::builder;
+
+} // namespace simdjson
+
+#endif // SIMDJSON_BUILDER_H

include/simdjson/builtin.h

@@ -20,10 +20,12 @@
 #include "simdjson/ppc64.h"
 #elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(westmere)
 #include "simdjson/westmere.h"
-#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lsx)
-#include "simdjson/lsx.h"
 #elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lasx)
 #include "simdjson/lasx.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lsx)
+#include "simdjson/lsx.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(rvv_vls)
+#include "simdjson/rvv-vls.h"
 #else
 #error Unknown SIMDJSON_BUILTIN_IMPLEMENTATION
 #endif

include/simdjson/builtin/base.h

@@ -21,6 +21,8 @@ namespace simdjson {
   namespace lsx {}
 #elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lasx)
   namespace lasx {}
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(rvv_vls)
+  namespace rvv_vls {}
 #else
 #error Unknown SIMDJSON_BUILTIN_IMPLEMENTATION
 #endif

include/simdjson/builtin/builder.h

@@ -0,0 +1,42 @@
+#ifndef SIMDJSON_BUILTIN_BUILDER_H
+#define SIMDJSON_BUILTIN_BUILDER_H
+
+#include "simdjson/builtin.h"
+#include "simdjson/builtin/base.h"
+
+#include "simdjson/generic/builder/dependencies.h"
+
+#define SIMDJSON_CONDITIONAL_INCLUDE
+
+#if SIMDJSON_BUILTIN_IMPLEMENTATION_IS(arm64)
+#include "simdjson/arm64/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(fallback)
+#include "simdjson/fallback/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(haswell)
+#include "simdjson/haswell/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(icelake)
+#include "simdjson/icelake/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(ppc64)
+#include "simdjson/ppc64/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(westmere)
+#include "simdjson/westmere/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lsx)
+#include "simdjson/lsx/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lasx)
+#include "simdjson/lasx/builder.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(rvv_vls)
+#include "simdjson/rvv-vls/builder.h"
+#else
+#error Unknown SIMDJSON_BUILTIN_IMPLEMENTATION
+#endif
+
+#undef SIMDJSON_CONDITIONAL_INCLUDE
+
+namespace simdjson {
+  /**
+   * @copydoc simdjson::SIMDJSON_BUILTIN_IMPLEMENTATION::builder
+   */
+  namespace builder = SIMDJSON_BUILTIN_IMPLEMENTATION::builder;
+} // namespace simdjson
+
+#endif // SIMDJSON_BUILTIN_BUILDER_H

include/simdjson/builtin/implementation.h

@@ -23,6 +23,8 @@
 #include "simdjson/lsx/implementation.h"
 #elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lasx)
 #include "simdjson/lasx/implementation.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(rvv_vls)
+#include "simdjson/rvv-vls/implementation.h"
 #else
 #error Unknown SIMDJSON_BUILTIN_IMPLEMENTATION
 #endif
@@ -39,4 +41,4 @@ namespace simdjson {
   const implementation * builtin_implementation();
 } // namespace simdjson
 
-#endif // SIMDJSON_BUILTIN_IMPLEMENTATION_H
+#endif // SIMDJSON_BUILTIN_IMPLEMENTATION_H

include/simdjson/builtin/ondemand.h

@@ -24,6 +24,8 @@
 #include "simdjson/lsx/ondemand.h"
 #elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(lasx)
 #include "simdjson/lasx/ondemand.h"
+#elif SIMDJSON_BUILTIN_IMPLEMENTATION_IS(rvv_vls)
+#include "simdjson/rvv-vls/ondemand.h"
 #else
 #error Unknown SIMDJSON_BUILTIN_IMPLEMENTATION
 #endif
@@ -37,4 +39,4 @@ namespace simdjson {
   namespace ondemand = SIMDJSON_BUILTIN_IMPLEMENTATION::ondemand;
 } // namespace simdjson
 
-#endif // SIMDJSON_BUILTIN_ONDEMAND_H
+#endif // SIMDJSON_BUILTIN_ONDEMAND_H

include/simdjson/common_defs.h

@@ -289,7 +289,9 @@ namespace std {
 // when the compiler is optimizing.
 // We only set SIMDJSON_DEVELOPMENT_CHECKS if both __OPTIMIZE__
 // and NDEBUG are not defined.
-#if !defined(__OPTIMIZE__) && !defined(NDEBUG)
+// We recognize _DEBUG as overriding __OPTIMIZE__ so that if both
+// __OPTIMIZE__ and _DEBUG are defined, we still set SIMDJSON_DEVELOPMENT_CHECKS.
+#if ((!defined(__OPTIMIZE__) || defined(_DEBUG)) && !defined(NDEBUG))
 #define SIMDJSON_DEVELOPMENT_CHECKS 1
 #endif // __OPTIMIZE__
 #endif // _MSC_VER

include/simdjson/dom.h

@@ -9,6 +9,7 @@
 #include "simdjson/dom/object.h"
 #include "simdjson/dom/parser.h"
 #include "simdjson/dom/serialization.h"
+#include "simdjson/dom/fractured_json.h"
 
 // Inline functions
 #include "simdjson/dom/array-inl.h"
@@ -19,5 +20,6 @@
 #include "simdjson/dom/parser-inl.h"
 #include "simdjson/internal/tape_ref-inl.h"
 #include "simdjson/dom/serialization-inl.h"
+#include "simdjson/dom/fractured_json-inl.h"
 
 #endif // SIMDJSON_DOM_H

include/simdjson/dom/fractured_json.h

@@ -0,0 +1,159 @@
+#ifndef SIMDJSON_DOM_FRACTURED_JSON_H
+#define SIMDJSON_DOM_FRACTURED_JSON_H
+
+#include "simdjson/dom/base.h"
+#include "simdjson/dom/element.h"
+
+namespace simdjson {
+
+/**
+ * Configuration options for FracturedJson formatting.
+ *
+ * FracturedJson intelligently chooses between different layout strategies
+ * (inline, compact multiline, table, expanded) based on content complexity,
+ * length, and structure similarity.
+ */
+struct fractured_json_options {
+  /**
+   * Maximum total characters per line (default: 120).
+   * Content exceeding this will be expanded to multiple lines.
+   */
+  size_t max_total_line_length = 120;
+
+  /**
+   * Maximum length for inlined elements (default: 80).
+   * Simple arrays/objects shorter than this may be rendered inline.
+   */
+  size_t max_inline_length = 80;
+
+  /**
+   * Maximum nesting depth for inline rendering (default: 2).
+   * Elements with complexity exceeding this will be expanded.
+   * Complexity 0 = scalar, 1 = flat array/object, 2 = one level of nesting.
+   */
+  size_t max_inline_complexity = 2;
+
+  /**
+   * Maximum complexity for compact array formatting (default: 1).
+   * Arrays with elements of this complexity or less may have multiple
+   * items per line.
+   */
+  size_t max_compact_array_complexity = 1;
+
+  /**
+   * Number of spaces per indentation level (default: 4).
+   */
+  size_t indent_spaces = 4;
+
+  /**
+   * Enable tabular formatting for arrays of similar objects (default: true).
+   * When enabled, arrays of objects with identical keys are formatted
+   * as aligned tables.
+   */
+  bool enable_table_format = true;
+
+  /**
+   * Minimum number of rows to trigger table mode (default: 3).
+   */
+  size_t min_table_rows = 3;
+
+  /**
+   * Similarity threshold for table detection (default: 0.8).
+   * Objects must share at least this fraction of keys to be formatted
+   * as a table.
+   */
+  double table_similarity_threshold = 0.8;
+
+  /**
+   * Enable compact multiline arrays (default: true).
+   * When enabled, arrays of simple elements may have multiple items
+   * per line.
+   */
+  bool enable_compact_multiline = true;
+
+  /**
+   * Maximum array items per line in compact mode (default: 10).
+   */
+  size_t max_items_per_line = 10;
+
+  /**
+   * Add space inside brackets for simple containers (default: true).
+   * When true: { "key": "value" }
+   * When false: {"key": "value"}
+   */
+  bool simple_bracket_padding = true;
+
+  /**
+   * Add space after colons (default: true).
+   * When true: "key": "value"
+   * When false: "key":"value"
+   */
+  bool colon_padding = true;
+
+  /**
+   * Add space after commas in inline content (default: true).
+   * When true: [1, 2, 3]
+   * When false: [1,2,3]
+   */
+  bool comma_padding = true;
+};
+
+/**
+ * Format JSON using FracturedJson formatting with default options.
+ *
+ * FracturedJson produces human-readable yet compact output by intelligently
+ * choosing between inline, compact multiline, table, and expanded layouts.
+ *
+ *   dom::parser parser;
+ *   element doc = parser.parse(json_string);
+ *   cout << fractured_json(doc) << endl;
+ */
+template <class T>
+std::string fractured_json(T x);
+
+/**
+ * Format JSON using FracturedJson formatting with custom options.
+ *
+ *   dom::parser parser;
+ *   element doc = parser.parse(json_string);
+ *   fractured_json_options opts;
+ *   opts.max_total_line_length = 80;
+ *   cout << fractured_json(doc, opts) << endl;
+ */
+template <class T>
+std::string fractured_json(T x, const fractured_json_options& options);
+
+#if SIMDJSON_EXCEPTIONS
+template <class T>
+std::string fractured_json(simdjson_result<T> x);
+
+template <class T>
+std::string fractured_json(simdjson_result<T> x, const fractured_json_options& options);
+#endif
+
+/**
+ * Format a JSON string using FracturedJson formatting.
+ *
+ * This is useful for formatting output from the builder/static reflection API
+ * or any valid JSON string.
+ *
+ *   // With static reflection
+ *   MyStruct data = {...};
+ *   auto minified = simdjson::to_json_string(data);
+ *   auto formatted = simdjson::fractured_json_string(minified.value());
+ *
+ *   // Or with any JSON string
+ *   std::string json = R"({"key":"value"})";
+ *   auto formatted = simdjson::fractured_json_string(json);
+ */
+inline std::string fractured_json_string(std::string_view json_str);
+
+/**
+ * Format a JSON string using FracturedJson formatting with custom options.
+ */
+inline std::string fractured_json_string(std::string_view json_str,
+                                          const fractured_json_options& options);
+
+} // namespace simdjson
+
+#endif // SIMDJSON_DOM_FRACTURED_JSON_H

include/simdjson/error-inl.h

@@ -8,7 +8,7 @@
 namespace simdjson {
 
 inline bool is_fatal(error_code error) noexcept {
-  return error == TAPE_ERROR || error == INCOMPLETE_ARRAY_OR_OBJECT;
+  return error == TAPE_ERROR || error == INCOMPLETE_ARRAY_OR_OBJECT || error == OUT_OF_ORDER_ITERATION || error == DEPTH_ERROR;
 }
 
 namespace internal {

include/simdjson/fallback/builder.h

@@ -0,0 +1,8 @@
+#ifndef SIMDJSON_FALLBACK_BUILDER_H
+#define SIMDJSON_FALLBACK_BUILDER_H
+
+#include "simdjson/fallback/begin.h"
+#include "simdjson/generic/builder/amalgamated.h"
+#include "simdjson/fallback/end.h"
+
+#endif // SIMDJSON_FALLBACK_BUILDER_H

include/simdjson/generic/base.h

@@ -17,10 +17,12 @@
 #include "simdjson/arm64/begin.h"
 #elif SIMDJSON_IMPLEMENTATION_PPC64
 #include "simdjson/ppc64/begin.h"
-#elif SIMDJSON_IMPLEMENTATION_LSX
-#include "simdjson/lsx/begin.h"
 #elif SIMDJSON_IMPLEMENTATION_LASX
 #include "simdjson/lasx/begin.h"
+#elif SIMDJSON_IMPLEMENTATION_LSX
+#include "simdjson/lsx/begin.h"
+#elif SIMDJSON_IMPLEMENTATION_RVV_VLS
+#include "simdjson/rvv-vls/begin.h"
 #elif SIMDJSON_IMPLEMENTATION_FALLBACK
 #include "simdjson/fallback/begin.h"
 #else
@@ -48,4 +50,4 @@ enum class number_type {
 } // namespace SIMDJSON_IMPLEMENTATION
 } // namespace simdjson
 
-#endif // SIMDJSON_GENERIC_BASE_H
+#endif // SIMDJSON_GENERIC_BASE_H

include/simdjson/generic/builder/amalgamated.h

@@ -0,0 +1,13 @@
+#if defined(SIMDJSON_CONDITIONAL_INCLUDE) && !defined(SIMDJSON_GENERIC_BUILDER_DEPENDENCIES_H)
+#error simdjson/generic/builder/dependencies.h must be included before simdjson/generic/builder/amalgamated.h!
+#endif
+
+#include "simdjson/generic/builder/json_string_builder.h"
+#include "simdjson/generic/builder/json_builder.h"
+#include "simdjson/generic/builder/fractured_json_builder.h"
+
+
+
+// JSON builder inline definitions
+#include "simdjson/generic/builder/json_string_builder-inl.h"
+

include/simdjson/generic/builder/dependencies.h

@@ -0,0 +1,14 @@
+#ifdef SIMDJSON_CONDITIONAL_INCLUDE
+#error simdjson/generic/builder/dependencies.h must be included before defining SIMDJSON_CONDITIONAL_INCLUDE!
+#endif
+
+#ifndef SIMDJSON_GENERIC_BUILDER_DEPENDENCIES_H
+#define SIMDJSON_GENERIC_BUILDER_DEPENDENCIES_H
+
+// Internal headers needed for builder generics.
+// All includes not under simdjson/generic/builder must be here!
+// Otherwise, amalgamation will fail.
+#include "simdjson/concepts.h"
+#include "simdjson/dom/fractured_json.h"
+
+#endif // SIMDJSON_GENERIC_BUILDER_DEPENDENCIES_H

include/simdjson/generic/builder/fractured_json_builder.h

@@ -0,0 +1,117 @@
+#ifndef SIMDJSON_GENERIC_FRACTURED_JSON_BUILDER_H
+#define SIMDJSON_GENERIC_FRACTURED_JSON_BUILDER_H
+
+#ifndef SIMDJSON_CONDITIONAL_INCLUDE
+#include "simdjson/generic/builder/json_builder.h"
+#include "simdjson/dom/fractured_json.h"
+#endif // SIMDJSON_CONDITIONAL_INCLUDE
+
+#if SIMDJSON_STATIC_REFLECTION
+
+namespace simdjson {
+namespace SIMDJSON_IMPLEMENTATION {
+namespace builder {
+
+/**
+ * Serialize an object to a FracturedJson-formatted string.
+ *
+ * FracturedJson produces human-readable yet compact JSON output by intelligently
+ * choosing between different layout strategies (inline, compact multiline, table,
+ * expanded) based on content complexity, length, and structure similarity.
+ *
+ * This function combines the builder's serialization with FracturedJson formatting:
+ * 1. Serializes the object to minified JSON using reflection
+ * 2. Parses and reformats using FracturedJson
+ *
+ * Example:
+ *   struct User { int id; std::string name; bool active; };
+ *   User user{1, "Alice", true};
+ *   auto result = to_fractured_json_string(user);
+ *   // result.value() == "{ \"id\": 1, \"name\": \"Alice\", \"active\": true }"
+ *
+ * @param obj The object to serialize (must be a reflectable type)
+ * @param opts FracturedJson formatting options
+ * @param initial_capacity Initial buffer capacity for serialization
+ * @return The formatted JSON string, or an error
+ */
+template <class T>
+simdjson_warn_unused simdjson_result<std::string> to_fractured_json_string(
+    const T& obj,
+    const fractured_json_options& opts = {},
+    size_t initial_capacity = string_builder::DEFAULT_INITIAL_CAPACITY) {
+  // Step 1: Serialize to minified JSON
+  std::string formatted;
+  auto error = to_json_string(obj, initial_capacity).get(formatted);
+  if (error) {
+    return error;
+  }
+
+  // Step 2: Reformat with FracturedJson
+  return fractured_json_string(formatted, opts);
+}
+
+/**
+ * Extract specific fields from an object and format with FracturedJson.
+ *
+ * Example:
+ *   struct User { int id; std::string name; std::string email; bool active; };
+ *   User user{1, "Alice", "alice@example.com", true};
+ *   auto result = extract_fractured_json<"id", "name">(user);
+ *   // result.value() == "{ \"id\": 1, \"name\": \"Alice\" }"
+ *
+ * @param obj The object to serialize
+ * @param opts FracturedJson formatting options
+ * @param initial_capacity Initial buffer capacity for serialization
+ * @return The formatted JSON string containing only the specified fields
+ */
+template<constevalutil::fixed_string... FieldNames, typename T>
+  requires(std::is_class_v<T> && (sizeof...(FieldNames) > 0))
+simdjson_warn_unused simdjson_result<std::string> extract_fractured_json(
+    const T& obj,
+    const fractured_json_options& opts = {},
+    size_t initial_capacity = string_builder::DEFAULT_INITIAL_CAPACITY) {
+  // Step 1: Extract fields to minified JSON
+  std::string formatted;
+  auto error = extract_from<FieldNames...>(obj, initial_capacity).get(formatted);
+  if (error) {
+    return error;
+  }
+
+  // Step 2: Reformat with FracturedJson
+  return fractured_json_string(formatted, opts);
+}
+
+} // namespace builder
+} // namespace SIMDJSON_IMPLEMENTATION
+
+// Global namespace convenience functions
+
+/**
+ * Serialize an object to a FracturedJson-formatted string.
+ * Global namespace version for convenience.
+ */
+template <class T>
+simdjson_warn_unused simdjson_result<std::string> to_fractured_json_string(
+    const T& obj,
+    const fractured_json_options& opts = {},
+    size_t initial_capacity = SIMDJSON_IMPLEMENTATION::builder::string_builder::DEFAULT_INITIAL_CAPACITY) {
+  return SIMDJSON_IMPLEMENTATION::builder::to_fractured_json_string(obj, opts, initial_capacity);
+}
+/**
+ * Extract specific fields from an object and format with FracturedJson.
+ * Global namespace version for convenience.
+ */
+template<constevalutil::fixed_string... FieldNames, typename T>
+  requires(std::is_class_v<T> && (sizeof...(FieldNames) > 0))
+simdjson_warn_unused simdjson_result<std::string> extract_fractured_json(
+    const T& obj,
+    const fractured_json_options& opts = {},
+    size_t initial_capacity = SIMDJSON_IMPLEMENTATION::builder::string_builder::DEFAULT_INITIAL_CAPACITY) {
+  return SIMDJSON_IMPLEMENTATION::builder::extract_fractured_json<FieldNames...>(obj, opts, initial_capacity);
+}
+
+} // namespace simdjson
+
+#endif // SIMDJSON_STATIC_REFLECTION
+
+#endif // SIMDJSON_GENERIC_FRACTURED_JSON_BUILDER_H

include/simdjson/generic/builder/json_builder.h

@@ -1,7 +1,3 @@
-/**
- * This file is part of the builder API. It is temporarily in the ondemand directory
- * but we will move it to a builder directory later.
- */
 #ifndef SIMDJSON_GENERIC_BUILDER_H
 
 #ifndef SIMDJSON_CONDITIONAL_INCLUDE
@@ -279,7 +275,7 @@ simdjson_warn_unused simdjson_result<std::string> to_json_string(const Z &z, siz
 }
 
 template <class Z>
-simdjson_warn_unused simdjson_error to_json(const Z &z, std::string &s, size_t initial_capacity = string_builder::DEFAULT_INITIAL_CAPACITY) {
+simdjson_warn_unused error_code to_json(const Z &z, std::string &s, size_t initial_capacity = string_builder::DEFAULT_INITIAL_CAPACITY) {
   string_builder b(initial_capacity);
   append(b, z);
   std::string_view view;
@@ -356,7 +352,7 @@ simdjson_warn_unused simdjson_result<std::string> to_json(const Z &z, size_t ini
   return std::string(s);
 }
 template <class Z>
-simdjson_warn_unused simdjson_error to_json(const Z &z, std::string &s, size_t initial_capacity = SIMDJSON_IMPLEMENTATION::builder::string_builder::DEFAULT_INITIAL_CAPACITY) {
+simdjson_warn_unused error_code to_json(const Z &z, std::string &s, size_t initial_capacity = SIMDJSON_IMPLEMENTATION::builder::string_builder::DEFAULT_INITIAL_CAPACITY) {
   SIMDJSON_IMPLEMENTATION::builder::string_builder b(initial_capacity);
   SIMDJSON_IMPLEMENTATION::builder::append(b, z);
   std::string_view view;

include/simdjson/generic/builder/json_string_builder-inl.h

@@ -1,7 +1,3 @@
-/**
- * This file is part of the builder API. It is temporarily in the ondemand
- * directory but we will move it to a builder directory later.
- */
 #include <array>
 #include <cstring>
 #include <type_traits>
@@ -33,9 +29,15 @@
 #endif
 #if SIMDJSON_EXPERIMENTAL_HAS_NEON
 #include <arm_neon.h>
+#ifdef _MSC_VER
+#include <intrin.h>
+#endif
 #endif
 #if SIMDJSON_EXPERIMENTAL_HAS_SSE2
 #include <emmintrin.h>
+#ifdef _MSC_VER
+#include <intrin.h>
+#endif
 #endif
 
 namespace simdjson {
@@ -143,10 +145,10 @@ simdjson_inline bool fast_needs_escaping(std::string_view view) {
 }
 #endif
 
-SIMDJSON_CONSTEXPR_LAMBDA inline size_t
-find_next_json_quotable_character(const std::string_view view,
-                                  size_t location) noexcept {
-
+// Scalar fallback for finding next quotable character
+SIMDJSON_CONSTEXPR_LAMBDA simdjson_inline size_t
+find_next_json_quotable_character_scalar(const std::string_view view,
+                                         size_t location) noexcept {
   for (auto pos = view.begin() + location; pos != view.end(); ++pos) {
     if (json_quotable_character[static_cast<uint8_t>(*pos)]) {
       return pos - view.begin();
@@ -155,6 +157,114 @@ find_next_json_quotable_character(const std::string_view view,
   return size_t(view.size());
 }
 
+// SIMD-accelerated position finding that directly locates the first quotable
+// character, combining detection and position extraction in a single pass to
+// minimize redundant work.
+#if SIMDJSON_EXPERIMENTAL_HAS_NEON
+simdjson_inline size_t
+find_next_json_quotable_character(const std::string_view view,
+                                  size_t location) noexcept {
+  const size_t len = view.size();
+  const uint8_t *ptr =
+      reinterpret_cast<const uint8_t *>(view.data()) + location;
+  size_t remaining = len - location;
+
+  // SIMD constants for characters requiring escape
+  uint8x16_t v34 = vdupq_n_u8(34);  // '"'
+  uint8x16_t v92 = vdupq_n_u8(92);  // '\\'
+  uint8x16_t v32 = vdupq_n_u8(32);  // control char threshold
+
+  while (remaining >= 16) {
+    uint8x16_t word = vld1q_u8(ptr);
+
+    // Check for quotable characters: '"', '\\', or control chars (< 32)
+    uint8x16_t needs_escape = vceqq_u8(word, v34);
+    needs_escape = vorrq_u8(needs_escape, vceqq_u8(word, v92));
+    needs_escape = vorrq_u8(needs_escape, vcltq_u8(word, v32));
+
+    if (vmaxvq_u32(vreinterpretq_u32_u8(needs_escape)) != 0) {
+      // Found quotable character - extract exact byte position using ctz
+      uint64x2_t as64 = vreinterpretq_u64_u8(needs_escape);
+      uint64_t lo = vgetq_lane_u64(as64, 0);
+      uint64_t hi = vgetq_lane_u64(as64, 1);
+      size_t offset = ptr - reinterpret_cast<const uint8_t *>(view.data());
+#ifdef _MSC_VER
+      unsigned long trailing_zero = 0;
+      if (lo != 0) {
+        _BitScanForward64(&trailing_zero, lo);
+        return offset + trailing_zero / 8;
+      } else {
+        _BitScanForward64(&trailing_zero, hi);
+        return offset + 8 + trailing_zero / 8;
+      }
+#else
+      if (lo != 0) {
+        return offset + __builtin_ctzll(lo) / 8;
+      } else {
+        return offset + 8 + __builtin_ctzll(hi) / 8;
+      }
+#endif
+    }
+    ptr += 16;
+    remaining -= 16;
+  }
+
+  // Scalar fallback for remaining bytes
+  size_t current = len - remaining;
+  return find_next_json_quotable_character_scalar(view, current);
+}
+#elif SIMDJSON_EXPERIMENTAL_HAS_SSE2
+simdjson_inline size_t
+find_next_json_quotable_character(const std::string_view view,
+                                  size_t location) noexcept {
+  const size_t len = view.size();
+  const uint8_t *ptr =
+      reinterpret_cast<const uint8_t *>(view.data()) + location;
+  size_t remaining = len - location;
+
+  // SIMD constants
+  __m128i v34 = _mm_set1_epi8(34);  // '"'
+  __m128i v92 = _mm_set1_epi8(92);  // '\\'
+  __m128i v31 = _mm_set1_epi8(31);  // for control char detection
+
+  while (remaining >= 16) {
+    __m128i word = _mm_loadu_si128(reinterpret_cast<const __m128i *>(ptr));
+
+    // Check for quotable characters
+    __m128i needs_escape = _mm_cmpeq_epi8(word, v34);
+    needs_escape = _mm_or_si128(needs_escape, _mm_cmpeq_epi8(word, v92));
+    needs_escape = _mm_or_si128(
+        needs_escape,
+        _mm_cmpeq_epi8(_mm_subs_epu8(word, v31), _mm_setzero_si128()));
+
+    int mask = _mm_movemask_epi8(needs_escape);
+    if (mask != 0) {
+      // Found quotable character - use trailing zero count to find position
+      size_t offset = ptr - reinterpret_cast<const uint8_t *>(view.data());
+#ifdef _MSC_VER
+      unsigned long trailing_zero = 0;
+      _BitScanForward(&trailing_zero, mask);
+      return offset + trailing_zero;
+#else
+      return offset + __builtin_ctz(mask);
+#endif
+    }
+    ptr += 16;
+    remaining -= 16;
+  }
+
+  // Scalar fallback for remaining bytes
+  size_t current = len - remaining;
+  return find_next_json_quotable_character_scalar(view, current);
+}
+#else
+SIMDJSON_CONSTEXPR_LAMBDA simdjson_inline size_t
+find_next_json_quotable_character(const std::string_view view,
+                                  size_t location) noexcept {
+  return find_next_json_quotable_character_scalar(view, location);
+}
+#endif
+
 SIMDJSON_CONSTEXPR_LAMBDA static std::string_view control_chars[] = {
     "\\u0000", "\\u0001", "\\u0002", "\\u0003", "\\u0004", "\\u0005", "\\u0006",
     "\\u0007", "\\b",     "\\t",     "\\n",     "\\u000b", "\\f",     "\\r",
@@ -167,7 +277,7 @@ SIMDJSON_CONSTEXPR_LAMBDA static std::string_view control_chars[] = {
 // control characters (U+0000 through U+001F). There are two-character sequence
 // escape representations of some popular characters:
 // \", \\, \b, \f, \n, \r, \t.
-SIMDJSON_CONSTEXPR_LAMBDA void escape_json_char(char c, char *&out) {
+SIMDJSON_CONSTEXPR_LAMBDA simdjson_inline void escape_json_char(char c, char *&out) {
   if (c == '"') {
     memcpy(out, "\\\"", 2);
     out += 2;
@@ -181,14 +291,20 @@ SIMDJSON_CONSTEXPR_LAMBDA void escape_json_char(char c, char *&out) {
   }
 }
 
+// Writes the escaped version of input to out, returning the number of bytes
+// written. Uses SIMD position finding to locate quotable characters efficiently.
 inline size_t write_string_escaped(const std::string_view input, char *out) {
   size_t mysize = input.size();
-  if (!fast_needs_escaping(input)) { // fast path!
+
+  // Use SIMD position finder directly - it returns mysize if no escape needed
+  size_t location = find_next_json_quotable_character(input, 0);
+  if (location == mysize) {
+    // Fast path: no escaping needed
     memcpy(out, input.data(), input.size());
     return input.size();
   }
+
   const char *const initout = out;
-  size_t location = find_next_json_quotable_character(input, 0);
   memcpy(out, input.data(), location);
   out += location;
   escape_json_char(input[location], out);
@@ -220,7 +336,7 @@ simdjson_inline bool string_builder::capacity_check(size_t upcoming_bytes) {
     return true;
   }
   // check for overflow, most of the time there is no overflow
-  if (simdjson_likely(position + upcoming_bytes < position)) {
+  if (simdjson_unlikely(position + upcoming_bytes < position)) {
     return false;
   }
   // We will rarely get here.
@@ -387,12 +503,29 @@ simdjson_inline void string_builder::append(number_type v) noexcept {
     }
   }
   else SIMDJSON_IF_CONSTEXPR(std::is_unsigned<number_type>::value) {
+    // Process 4 digits at a time instead of 2, reducing store operations
+    // and divisions by approximately half for large numbers.
     constexpr size_t max_number_size = 20;
     if (capacity_check(max_number_size)) {
       using unsigned_type = typename std::make_unsigned<number_type>::type;
       unsigned_type pv = static_cast<unsigned_type>(v);
       size_t dc = internal::digit_count(pv);
       char *write_pointer = buffer.get() + position + dc - 1;
+
+      // Process 4 digits per iteration for large numbers
+      while (pv >= 10000) {
+        unsigned_type q = pv / 10000;
+        unsigned_type r = pv % 10000;
+        unsigned_type r_hi = r / 100;  // High 2 digits of remainder
+        unsigned_type r_lo = r % 100;  // Low 2 digits of remainder
+        // Write low 2 digits first (rightmost), then high 2 digits
+        memcpy(write_pointer - 1, &internal::decimal_table[r_lo * 2], 2);
+        memcpy(write_pointer - 3, &internal::decimal_table[r_hi * 2], 2);
+        write_pointer -= 4;
+        pv = q;
+      }
+
+      // Handle remaining 1-4 digits with original 2-digit loop
       while (pv >= 100) {
         memcpy(write_pointer - 1, &internal::decimal_table[(pv % 100) * 2], 2);
         write_pointer -= 2;
@@ -407,6 +540,7 @@ simdjson_inline void string_builder::append(number_type v) noexcept {
     }
   }
   else SIMDJSON_IF_CONSTEXPR(std::is_integral<number_type>::value) {
+    // Same 4-digit batching as unsigned path for signed integers
     constexpr size_t max_number_size = 20;
     if (capacity_check(max_number_size)) {
       using unsigned_type = typename std::make_unsigned<number_type>::type;
@@ -420,6 +554,20 @@ simdjson_inline void string_builder::append(number_type v) noexcept {
       buffer.get()[position] = '-';
       position += negative ? 1 : 0;
       char *write_pointer = buffer.get() + position + dc - 1;
+
+      // Process 4 digits per iteration for large numbers
+      while (pv >= 10000) {
+        unsigned_type q = pv / 10000;
+        unsigned_type r = pv % 10000;
+        unsigned_type r_hi = r / 100;
+        unsigned_type r_lo = r % 100;
+        memcpy(write_pointer - 1, &internal::decimal_table[r_lo * 2], 2);
+        memcpy(write_pointer - 3, &internal::decimal_table[r_hi * 2], 2);
+        write_pointer -= 4;
+        pv = q;
+      }
+
+      // Handle remaining 1-4 digits
       while (pv >= 100) {
         memcpy(write_pointer - 1, &internal::decimal_table[(pv % 100) * 2], 2);
         write_pointer -= 2;

include/simdjson/generic/builder/json_string_builder.h

@@ -1,7 +1,3 @@
-/**
- * This file is part of the builder API. It is temporarily in the ondemand directory
- * but we will move it to a builder directory later.
- */
 #ifndef SIMDJSON_GENERIC_STRING_BUILDER_H
 
 #ifndef SIMDJSON_CONDITIONAL_INCLUDE
@@ -284,7 +280,7 @@ simdjson_warn_unused simdjson_result<std::string> to_json(const Z &z, size_t ini
   return std::string(s);
 }
 template <class Z>
-simdjson_warn_unused simdjson_error to_json(const Z &z, std::string &s, size_t initial_capacity = simdjson::SIMDJSON_IMPLEMENTATION::builder::string_builder::DEFAULT_INITIAL_CAPACITY) {
+simdjson_warn_unused error_code to_json(const Z &z, std::string &s, size_t initial_capacity = simdjson::SIMDJSON_IMPLEMENTATION::builder::string_builder::DEFAULT_INITIAL_CAPACITY) {
   simdjson::SIMDJSON_IMPLEMENTATION::builder::string_builder b(initial_capacity);
   b.append(z);
   std::string_view sv;

include/simdjson/generic/ondemand/amalgamated.h

@@ -1,4 +1,4 @@
-#if defined(SIMDJSON_CONDITIONAL_INCLUDE) && !defined(SIMDJSON_GENERIC_ONDEMAND_DEPENDENCIES_H)
+#if defined(SIMDJSON_CONDITIONAL_INCLUDE) && !defined(SIMDJSON_GENERIC_BUILDER_DEPENDENCIES_H)
 #error simdjson/generic/ondemand/dependencies.h must be included before simdjson/generic/ondemand/amalgamated.h!
 #endif
 
@@ -14,9 +14,6 @@
 #include "simdjson/generic/ondemand/raw_json_string.h"
 #include "simdjson/generic/ondemand/parser.h"
 
-// JSON builder - needed for extract_into functionality
-#include "simdjson/generic/ondemand/json_string_builder.h"
-
 // All other declarations
 #include "simdjson/generic/ondemand/array.h"
 #include "simdjson/generic/ondemand/array_iterator.h"
@@ -44,13 +41,9 @@
 #include "simdjson/generic/ondemand/object_iterator-inl.h"
 #include "simdjson/generic/ondemand/parser-inl.h"
 #include "simdjson/generic/ondemand/raw_json_string-inl.h"
-#include "simdjson/generic/ondemand/serialization-inl.h"
 #include "simdjson/generic/ondemand/token_iterator-inl.h"
 #include "simdjson/generic/ondemand/value_iterator-inl.h"
-
-// JSON builder inline definitions
-#include "simdjson/generic/ondemand/json_string_builder-inl.h"
-#include "simdjson/generic/ondemand/json_builder.h"
+#include "simdjson/generic/ondemand/serialization-inl.h"
 
 // JSON path accessor (compile-time) - must be after inline definitions
 #include "simdjson/generic/ondemand/compile_time_accessors.h"

include/simdjson/generic/ondemand/array_iterator-inl.h

@@ -17,6 +17,10 @@ simdjson_inline array_iterator::array_iterator(const value_iterator &_iter) noex
 {}
 
 simdjson_inline simdjson_result<value> array_iterator::operator*() noexcept {
+#if SIMDJSON_DEVELOPMENT_CHECKS
+   SIMDJSON_ASSUME(!has_been_referenced);
+   has_been_referenced = true;
+#endif
   if (iter.error()) { iter.abandon(); return iter.error(); }
   return value(iter.child());
 }
@@ -27,6 +31,9 @@ simdjson_inline bool array_iterator::operator!=(const array_iterator &) const no
   return iter.is_open();
 }
 simdjson_inline array_iterator &array_iterator::operator++() noexcept {
+#if SIMDJSON_DEVELOPMENT_CHECKS
+   has_been_referenced = false;
+#endif
   error_code error;
   // PERF NOTE this is a safety rail ... users should exit loops as soon as they receive an error, so we'll never get here.
   // However, it does not seem to make a perf difference, so we add it out of an abundance of caution.

include/simdjson/generic/ondemand/array_iterator.h

@@ -2,6 +2,7 @@
 
 #ifndef SIMDJSON_CONDITIONAL_INCLUDE
 #define SIMDJSON_GENERIC_ONDEMAND_ARRAY_ITERATOR_H
+#include <iterator>
 #include "simdjson/generic/implementation_simdjson_result_base.h"
 #include "simdjson/generic/ondemand/base.h"
 #include "simdjson/generic/ondemand/value_iterator.h"
@@ -17,11 +18,17 @@ namespace ondemand {
  *
  * This is an input_iterator, meaning:
  * - It is forward-only
- * - * must be called exactly once per element.
+ * - * must be called at most once per element.
  * - ++ must be called exactly once in between each * (*, ++, *, ++, * ...)
  */
 class array_iterator {
 public:
+  using iterator_category = std::input_iterator_tag;
+  using value_type = simdjson_result<value>;
+  using difference_type = std::ptrdiff_t;
+  using pointer = void;
+  using reference = value_type;
+
   /** Create a new, invalid array iterator. */
   simdjson_inline array_iterator() noexcept = default;
 
@@ -65,6 +72,9 @@ public:
   simdjson_warn_unused simdjson_inline bool at_end() const noexcept;
 
 private:
+#if SIMDJSON_DEVELOPMENT_CHECKS
+   bool has_been_referenced{false};
+#endif
   value_iterator iter{};
 
   simdjson_inline array_iterator(const value_iterator &iter) noexcept;
@@ -82,6 +92,12 @@ namespace simdjson {
 
 template<>
 struct simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::array_iterator> : public SIMDJSON_IMPLEMENTATION::implementation_simdjson_result_base<SIMDJSON_IMPLEMENTATION::ondemand::array_iterator> {
+  using iterator_category = std::input_iterator_tag;
+  using value_type = simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::value>;
+  using difference_type = std::ptrdiff_t;
+  using pointer = void;
+  using reference = value_type;
+
   simdjson_inline simdjson_result(SIMDJSON_IMPLEMENTATION::ondemand::array_iterator &&value) noexcept; ///< @private
   simdjson_inline simdjson_result(error_code error) noexcept; ///< @private
   simdjson_inline simdjson_result() noexcept = default;

include/simdjson/generic/ondemand/dependencies.h

@@ -8,7 +8,6 @@
 // Internal headers needed for ondemand generics.
 // All includes not under simdjson/generic/ondemand must be here!
 // Otherwise, amalgamation will fail.
-#include "simdjson/concepts.h"
 #include "simdjson/dom/base.h" // for MINIMAL_DOCUMENT_CAPACITY
 #include "simdjson/implementation.h"
 #include "simdjson/padded_string.h"

include/simdjson/generic/ondemand/json_iterator-inl.h

@@ -215,11 +215,10 @@ simdjson_inline void json_iterator::assert_more_tokens(uint32_t required_tokens)
 }
 
 simdjson_inline void json_iterator::assert_valid_position(token_position position) const noexcept {
+  (void)position; // Suppress unused parameter warning
 #ifndef SIMDJSON_CLANG_VISUAL_STUDIO
   SIMDJSON_ASSUME( position >= &parser->implementation->structural_indexes[0] );
   SIMDJSON_ASSUME( position < &parser->implementation->structural_indexes[parser->implementation->n_structural_indexes] );
-#else
-  (void)position; // Suppress unused parameter warning
 #endif
 }
 
@@ -358,7 +357,11 @@ simdjson_inline token_position json_iterator::position() const noexcept {
 simdjson_inline simdjson_result<std::string_view> json_iterator::unescape(raw_json_string in, bool allow_replacement) noexcept {
 #if SIMDJSON_DEVELOPMENT_CHECKS
   auto result = parser->unescape(in, _string_buf_loc, allow_replacement);
+#if !defined(SIMDJSON_VISUAL_STUDIO) && !defined(SIMDJSON_CLANG_VISUAL_STUDIO)
+  // Under Visual Studio, the next SIMDJSON_ASSUME fails with: the argument
+  // has side effects that will be discarded.
   SIMDJSON_ASSUME(!parser->string_buffer_overflow(_string_buf_loc));
+#endif // !defined(SIMDJSON_VISUAL_STUDIO) && !defined(SIMDJSON_CLANG_VISUAL_STUDIO)
   return result;
 #else
   return parser->unescape(in, _string_buf_loc, allow_replacement);
@@ -368,7 +371,11 @@ simdjson_inline simdjson_result<std::string_view> json_iterator::unescape(raw_js
 simdjson_inline simdjson_result<std::string_view> json_iterator::unescape_wobbly(raw_json_string in) noexcept {
 #if SIMDJSON_DEVELOPMENT_CHECKS
   auto result = parser->unescape_wobbly(in, _string_buf_loc);
+#if !defined(SIMDJSON_VISUAL_STUDIO) && !defined(SIMDJSON_CLANG_VISUAL_STUDIO)
+  // Under Visual Studio, the next SIMDJSON_ASSUME fails with: the argument
+  // has side effects that will be discarded.
   SIMDJSON_ASSUME(!parser->string_buffer_overflow(_string_buf_loc));
+#endif // !defined(SIMDJSON_VISUAL_STUDIO) && !defined(SIMDJSON_CLANG_VISUAL_STUDIO)
   return result;
 #else
   return parser->unescape_wobbly(in, _string_buf_loc);

include/simdjson/generic/ondemand/object.h

@@ -27,6 +27,13 @@ public:
    */
   simdjson_inline object() noexcept = default;
 
+  /**
+   * Get an iterator to the start of the object. We recommend using a range-based for loop.
+   *
+   * Using the iterator directly is also possible but error-prone and discouraged. In particular,
+   * you must dereference the iterator exactly once per iteration (before calling '++').
+   * Doing otherwise is unsafe and may lead to errors. You are responsible for ensuring
+   */
   simdjson_inline simdjson_result<object_iterator> begin() noexcept;
   simdjson_inline simdjson_result<object_iterator> end() noexcept;
   /**

include/simdjson/generic/ondemand/object_iterator-inl.h

@@ -21,6 +21,11 @@ simdjson_inline object_iterator::object_iterator(const value_iterator &_iter) no
 {}
 
 simdjson_inline simdjson_result<field> object_iterator::operator*() noexcept {
+#if SIMDJSON_DEVELOPMENT_CHECKS
+  // We must call * once per iteration.
+  SIMDJSON_ASSUME(!has_been_referenced);
+  has_been_referenced = true;
+#endif
   error_code error = iter.error();
   if (error) { iter.abandon(); return error; }
   auto result = field::start(iter);
@@ -39,6 +44,11 @@ simdjson_inline bool object_iterator::operator!=(const object_iterator &) const
 SIMDJSON_PUSH_DISABLE_WARNINGS
 SIMDJSON_DISABLE_STRICT_OVERFLOW_WARNING
 simdjson_inline object_iterator &object_iterator::operator++() noexcept {
+#if SIMDJSON_DEVELOPMENT_CHECKS
+   // Before calling ++, we must have called *.
+   SIMDJSON_ASSUME(has_been_referenced);
+   has_been_referenced = false;
+#endif
   // TODO this is a safety rail ... users should exit loops as soon as they receive an error.
   // Nonetheless, let's see if performance is OK with this if statement--the compiler may give it to us for free.
   if (!iter.is_open()) { return *this; } // Iterator will be released if there is an error

include/simdjson/generic/ondemand/object_iterator.h

@@ -32,9 +32,14 @@ public:
   // Assumes it's being compared with the end. true if depth >= iter->depth.
   simdjson_inline bool operator!=(const object_iterator &) const noexcept;
   // Checks for ']' and ','
+  // YOU MUST NOT CALL THIS IF operator* YIELDED AN ERROR.
+  // YOU MUST NOT CALL THIS WITHOUT A CORRESPONDING operator* CALL.
   simdjson_inline object_iterator &operator++() noexcept;
 
 private:
+#if SIMDJSON_DEVELOPMENT_CHECKS
+   bool has_been_referenced{false};
+#endif
   /**
    * The underlying JSON iterator.
    *

include/simdjson/generic/ondemand/serialization-inl.h

@@ -10,7 +10,7 @@
 #include "simdjson/generic/ondemand/serialization.h"
 #include "simdjson/generic/ondemand/value.h"
 #if SIMDJSON_STATIC_REFLECTION
-#include "simdjson/generic/ondemand/json_builder.h"
+#include "simdjson/generic/builder/json_builder.h"
 #endif
 #endif // SIMDJSON_CONDITIONAL_INCLUDE
 

include/simdjson/generic/ondemand/value.h

@@ -814,7 +814,7 @@ public:
    * in question is large. The fact that the extra code is there also bumps the executable size.
    *
    * We default operator[] on find_field_unordered() for convenience.
-   * It is the defaul because it would be highly surprising (and hard to debug) if the
+   * It is the default because it would be highly surprising (and hard to debug) if the
    * default behavior failed to look up a field just because it was in the wrong order--and many
    * APIs assume this. Therefore, you must be explicit if you want to treat objects as out of order.
    *

include/simdjson/generic/ondemand/value_iterator-inl.h

@@ -94,7 +94,6 @@ simdjson_warn_unused simdjson_inline error_code value_iterator::end_container()
 
 simdjson_warn_unused simdjson_inline simdjson_result<bool> value_iterator::has_next_field() noexcept {
   assert_at_next();
-
   // It's illegal to call this unless there are more tokens: anything that ends in } or ] is
   // obligated to verify there are more tokens if they are not the top level.
   switch (*_json_iter->return_current_and_advance()) {
@@ -516,9 +515,13 @@ simdjson_warn_unused simdjson_inline simdjson_result<std::string_view> value_ite
 template <typename string_type>
 simdjson_warn_unused simdjson_inline error_code value_iterator::get_string(string_type& receiver, bool allow_replacement) noexcept {
   std::string_view content;
+  // Save the string buffer location so that we can restore it after get_string
+  auto saved_string_buf_loc = _json_iter->string_buf_loc();
   auto err = get_string(allow_replacement).get(content);
   if (err) { return err; }
   receiver = content;
+  // Restore the string buffer location, effectively discarding any temporary string storage
+  _json_iter->string_buf_loc() = saved_string_buf_loc;
   return SUCCESS;
 }
 simdjson_warn_unused simdjson_inline simdjson_result<std::string_view> value_iterator::get_wobbly_string() noexcept {
@@ -658,9 +661,13 @@ simdjson_warn_unused simdjson_inline simdjson_result<std::string_view> value_ite
 template <typename string_type>
 simdjson_warn_unused simdjson_inline error_code value_iterator::get_root_string(string_type& receiver, bool check_trailing, bool allow_replacement) noexcept {
   std::string_view content;
+  // Save the string buffer location so that we can restore it after get_string
+  auto saved_string_buf_loc = _json_iter->string_buf_loc();
   auto err = get_root_string(check_trailing, allow_replacement).get(content);
   if (err) { return err; }
   receiver = content;
+  // Restore the string buffer location, effectively discarding any temporary string storage
+  _json_iter->string_buf_loc() = saved_string_buf_loc;
   return SUCCESS;
 }
 simdjson_warn_unused simdjson_inline simdjson_result<std::string_view> value_iterator::get_root_wobbly_string(bool check_trailing) noexcept {
@@ -967,6 +974,9 @@ simdjson_inline bool value_iterator::is_at_key() const noexcept {
   // Keys are at the same depth as the object.
   // Note here that we could be safer and check that we are within an object,
   // but we do not.
+  //
+  // As long as we are at the object's depth, in a valid document,
+  // we will only ever be at { , : or the actual string key: ".
   return _depth == _json_iter->_depth && *_json_iter->peek() == '"';
 }
 

include/simdjson/generic/ondemand/value_iterator.h

@@ -472,6 +472,7 @@ protected:
 
   friend class document;
   friend class object;
+  friend class object_iterator;
   friend class array;
   friend class value;
   friend class field;

include/simdjson/haswell/builder.h

@@ -0,0 +1,8 @@
+#ifndef SIMDJSON_HASWELL_BUILDER_H
+#define SIMDJSON_HASWELL_BUILDER_H
+
+#include "simdjson/haswell/begin.h"
+#include "simdjson/generic/builder/amalgamated.h"
+#include "simdjson/haswell/end.h"
+
+#endif // SIMDJSON_HASWELL_BUILDER_H

include/simdjson/haswell/simd.h

@@ -300,6 +300,7 @@ namespace simd {
     static constexpr int NUM_CHUNKS = 64 / sizeof(simd8<T>);
     static_assert(NUM_CHUNKS == 2, "Haswell kernel should use two registers per 64-byte block.");
     const simd8<T> chunks[NUM_CHUNKS];
+    template<int idx> simd8<uint8_t> get() const { return idx < NUM_CHUNKS ? chunks[idx] : simd8<T>(); }
 
     simd8x64(const simd8x64<T>& o) = delete; // no copy allowed
     simd8x64<T>& operator=(const simd8<T>& other) = delete; // no assignment allowed

include/simdjson/icelake/builder.h

@@ -0,0 +1,8 @@
+#ifndef SIMDJSON_ICELAKE_BUILDER_H
+#define SIMDJSON_ICELAKE_BUILDER_H
+
+#include "simdjson/icelake/begin.h"
+#include "simdjson/generic/builder/amalgamated.h"
+#include "simdjson/icelake/end.h"
+
+#endif // SIMDJSON_ICELAKE_BUILDER_H

include/simdjson/icelake/simd.h

@@ -322,6 +322,7 @@ namespace simd {
     static constexpr int NUM_CHUNKS = 64 / sizeof(simd8<T>);
     static_assert(NUM_CHUNKS == 1, "Icelake kernel should use one register per 64-byte block.");
     const simd8<T> chunks[NUM_CHUNKS];
+    template<int idx> simd8<uint8_t> get() const { return idx < NUM_CHUNKS ? chunks[idx] : simd8<T>(); }
 
     simd8x64(const simd8x64<T>& o) = delete; // no copy allowed
     simd8x64<T>& operator=(const simd8<T>& other) = delete; // no assignment allowed

include/simdjson/implementation_detection.h

@@ -12,6 +12,8 @@
 #define SIMDJSON_IMPLEMENTATION_ID_westmere 6
 #define SIMDJSON_IMPLEMENTATION_ID_lsx 7
 #define SIMDJSON_IMPLEMENTATION_ID_lasx 8
+//#define SIMDJSON_IMPLEMENTATION_ID_rvv 9
+#define SIMDJSON_IMPLEMENTATION_ID_rvv_vls 10
 
 #define SIMDJSON_IMPLEMENTATION_ID_FOR(IMPL) SIMDJSON_CAT(SIMDJSON_IMPLEMENTATION_ID_, IMPL)
 #define SIMDJSON_IMPLEMENTATION_ID SIMDJSON_IMPLEMENTATION_ID_FOR(SIMDJSON_IMPLEMENTATION)
@@ -113,22 +115,27 @@
 #endif
 
 #ifndef SIMDJSON_IMPLEMENTATION_LASX
-#define SIMDJSON_IMPLEMENTATION_LASX (SIMDJSON_IS_LOONGARCH64 && __loongarch_asx)
+#define SIMDJSON_IMPLEMENTATION_LASX (SIMDJSON_IS_LSX)
 #endif
-#define SIMDJSON_CAN_ALWAYS_RUN_LASX (SIMDJSON_IMPLEMENTATION_LASX)
+#define SIMDJSON_CAN_ALWAYS_RUN_LASX (SIMDJSON_IS_LASX)
 
 #ifndef SIMDJSON_IMPLEMENTATION_LSX
 #if SIMDJSON_CAN_ALWAYS_RUN_LASX
 #define SIMDJSON_IMPLEMENTATION_LSX 0
 #else
-#define SIMDJSON_IMPLEMENTATION_LSX (SIMDJSON_IS_LOONGARCH64 && __loongarch_sx)
+#define SIMDJSON_IMPLEMENTATION_LSX (SIMDJSON_IS_LSX)
 #endif
 #endif
 #define SIMDJSON_CAN_ALWAYS_RUN_LSX (SIMDJSON_IMPLEMENTATION_LSX)
 
+#define SIMDJSON_CAN_ALWAYS_RUN_RVV_VLS SIMDJSON_IS_RVV_VLS
+#ifndef SIMDJSON_IMPLEMENTATION_RVV_VLS
+#define SIMDJSON_IMPLEMENTATION_RVV_VLS SIMDJSON_CAN_ALWAYS_RUN_RVV_VLS
+#endif
+
 // Default Fallback to on unless a builtin implementation has already been selected.
 #ifndef SIMDJSON_IMPLEMENTATION_FALLBACK
-#if SIMDJSON_CAN_ALWAYS_RUN_ARM64 || SIMDJSON_CAN_ALWAYS_RUN_ICELAKE || SIMDJSON_CAN_ALWAYS_RUN_HASWELL || SIMDJSON_CAN_ALWAYS_RUN_WESTMERE || SIMDJSON_CAN_ALWAYS_RUN_PPC64 || SIMDJSON_CAN_ALWAYS_RUN_LSX || SIMDJSON_CAN_ALWAYS_RUN_LASX
+#if SIMDJSON_CAN_ALWAYS_RUN_ARM64 || SIMDJSON_CAN_ALWAYS_RUN_ICELAKE || SIMDJSON_CAN_ALWAYS_RUN_HASWELL || SIMDJSON_CAN_ALWAYS_RUN_WESTMERE || SIMDJSON_CAN_ALWAYS_RUN_PPC64 || SIMDJSON_CAN_ALWAYS_RUN_LSX || SIMDJSON_CAN_ALWAYS_RUN_LASX || SIMDJSON_CAN_ALWAYS_RUN_RVV_VLS
 // if anything at all except fallback can always run, then disable fallback.
 #define SIMDJSON_IMPLEMENTATION_FALLBACK 0
 #else
@@ -154,6 +161,8 @@
 #define SIMDJSON_BUILTIN_IMPLEMENTATION lsx
 #elif SIMDJSON_CAN_ALWAYS_RUN_LASX
 #define SIMDJSON_BUILTIN_IMPLEMENTATION lasx
+#elif SIMDJSON_CAN_ALWAYS_RUN_RVV_VLS
+#define SIMDJSON_BUILTIN_IMPLEMENTATION rvv_vls
 #elif SIMDJSON_CAN_ALWAYS_RUN_FALLBACK
 #define SIMDJSON_BUILTIN_IMPLEMENTATION fallback
 #else
@@ -165,4 +174,4 @@
 #define SIMDJSON_BUILTIN_IMPLEMENTATION_ID SIMDJSON_IMPLEMENTATION_ID_FOR(SIMDJSON_BUILTIN_IMPLEMENTATION)
 #define SIMDJSON_BUILTIN_IMPLEMENTATION_IS(IMPL) SIMDJSON_BUILTIN_IMPLEMENTATION_ID == SIMDJSON_IMPLEMENTATION_ID_FOR(IMPL)
 
-#endif // SIMDJSON_IMPLEMENTATION_DETECTION_H
+#endif // SIMDJSON_IMPLEMENTATION_DETECTION_H

include/simdjson/internal/fractured_formatter.h

@@ -0,0 +1,161 @@
+#ifndef SIMDJSON_INTERNAL_FRACTURED_FORMATTER_H
+#define SIMDJSON_INTERNAL_FRACTURED_FORMATTER_H
+
+#include "simdjson/dom/serialization.h"
+#include "simdjson/dom/fractured_json.h"
+#include "simdjson/internal/json_structure_analyzer.h"
+
+namespace simdjson {
+namespace internal {
+
+/**
+ * Fractured JSON formatter using CRTP pattern.
+ *
+ * This formatter intelligently chooses between different layout modes
+ * (inline, compact multiline, table, expanded) based on pre-computed
+ * structure metrics.
+ */
+class fractured_formatter : public base_formatter<fractured_formatter> {
+public:
+  explicit fractured_formatter(const fractured_json_options& opts = {});
+
+  /** CRTP hook: print newline (context-aware) */
+  simdjson_inline void print_newline();
+
+  /** CRTP hook: print indentation */
+  simdjson_inline void print_indents(size_t depth);
+
+  /** CRTP hook: print space (context-aware) */
+  simdjson_inline void print_space();
+
+  /** Set the current layout mode */
+  void set_layout_mode(layout_mode mode);
+
+  /** Get the current layout mode */
+  layout_mode get_layout_mode() const;
+
+  /** Set current depth for formatting decisions */
+  void set_depth(size_t depth);
+
+  /** Get current depth */
+  size_t get_depth() const;
+
+  /** Track current line length for compact multiline decisions */
+  void track_line_length(size_t chars);
+
+  /** Reset line length (after newline) */
+  void reset_line_length();
+
+  /** Get current line length */
+  size_t get_line_length() const;
+
+  /** Check if we should break to a new line in compact mode */
+  bool should_break_line(size_t upcoming_length) const;
+
+  /** Get the options */
+  const fractured_json_options& options() const;
+
+  // Table formatting support
+  /** Begin a table row */
+  void begin_table_row();
+
+  /** End a table row */
+  void end_table_row();
+
+  /** Set column widths for table alignment */
+  void set_column_widths(const std::vector<size_t>& widths);
+
+  /** Get current column index in table mode */
+  size_t get_column_index() const;
+
+  /** Advance to next column */
+  void next_column();
+
+  /** Add padding to align with column width */
+  void align_to_column_width(size_t actual_width);
+
+private:
+  fractured_json_options options_;
+  layout_mode current_layout_ = layout_mode::EXPANDED;
+  size_t current_depth_ = 0;
+  size_t current_line_length_ = 0;
+
+  // Table state
+  bool in_table_mode_ = false;
+  std::vector<size_t> column_widths_;
+  size_t current_column_ = 0;
+};
+
+/**
+ * Specialized string builder for fractured JSON formatting.
+ *
+ * This builder performs two passes:
+ * 1. Analyze the structure to compute metrics
+ * 2. Format using the metrics to make layout decisions
+ */
+class fractured_string_builder {
+public:
+  fractured_string_builder(const fractured_json_options& opts = {});
+
+  /** Append a DOM element with fractured formatting */
+  void append(const dom::element& value);
+
+  /** Append a DOM array with fractured formatting */
+  void append(const dom::array& value);
+
+  /** Append a DOM object with fractured formatting */
+  void append(const dom::object& value);
+
+  /** Clear the builder */
+  simdjson_inline void clear();
+
+  /** Get the formatted string */
+  simdjson_inline std::string_view str() const;
+
+private:
+  fractured_formatter format_;
+  structure_analyzer analyzer_;
+  fractured_json_options options_;
+
+  /** Format an element using pre-computed metrics */
+  void format_element(const dom::element& elem, const element_metrics& metrics, size_t depth);
+
+  /** Format an array with the appropriate layout */
+  void format_array(const dom::array& arr, const element_metrics& metrics, size_t depth);
+
+  /** Format an array inline: [1, 2, 3] */
+  void format_array_inline(const dom::array& arr, const element_metrics& metrics);
+
+  /** Format an array with compact multiline: multiple items per line */
+  void format_array_compact_multiline(const dom::array& arr, const element_metrics& metrics, size_t depth);
+
+  /** Format an array as a table */
+  void format_array_as_table(const dom::array& arr, const element_metrics& metrics, size_t depth);
+
+  /** Format an array expanded: one item per line */
+  void format_array_expanded(const dom::array& arr, const element_metrics& metrics, size_t depth);
+
+  /** Format an object with the appropriate layout */
+  void format_object(const dom::object& obj, const element_metrics& metrics, size_t depth);
+
+  /** Format an object inline: {"a": 1, "b": 2} */
+  void format_object_inline(const dom::object& obj, const element_metrics& metrics);
+
+  /** Format an object expanded: one key per line */
+  void format_object_expanded(const dom::object& obj, const element_metrics& metrics, size_t depth);
+
+  /** Format a scalar value */
+  void format_scalar(const dom::element& elem);
+
+  /** Calculate column widths for table formatting */
+  std::vector<size_t> calculate_column_widths(const dom::array& arr,
+                                               const std::vector<std::string>& columns) const;
+
+  /** Measure the actual formatted length of a value (for alignment) */
+  size_t measure_value_length(const dom::element& elem) const;
+};
+
+} // namespace internal
+} // namespace simdjson
+
+#endif // SIMDJSON_INTERNAL_FRACTURED_FORMATTER_H

include/simdjson/internal/instruction_set.h

@@ -69,6 +69,8 @@ enum instruction_set {
   AVX512VBMI2 = 0x10000,
   LSX = 0x20000,
   LASX = 0x40000,
+  //RVV = 0x80000,
+  RVV_VLS = 0x100000,
 };
 
 } // namespace internal

include/simdjson/internal/json_structure_analyzer.h

@@ -0,0 +1,169 @@
+#ifndef SIMDJSON_INTERNAL_JSON_STRUCTURE_ANALYZER_H
+#define SIMDJSON_INTERNAL_JSON_STRUCTURE_ANALYZER_H
+
+#include "simdjson/dom/base.h"
+#include "simdjson/dom/element.h"
+#include "simdjson/dom/array.h"
+#include "simdjson/dom/object.h"
+#include "simdjson/dom/fractured_json.h"
+#include "simdjson/internal/tape_type.h"
+
+#include <vector>
+#include <string>
+#include <string_view>
+#include <set>
+
+namespace simdjson {
+namespace internal {
+
+/**
+ * Layout mode for fractured JSON formatting.
+ */
+enum class layout_mode {
+  INLINE,              // Single line: [1, 2, 3] or {"a": 1}
+  COMPACT_MULTILINE,   // Multiple items per line with breaks
+  TABLE,               // Tabular format for arrays of similar objects
+  EXPANDED             // Traditional multi-line with indentation
+};
+
+/**
+ * Metrics computed for a JSON element during structure analysis.
+ * These metrics drive layout decisions and contain child metrics for recursive formatting.
+ */
+struct element_metrics {
+  /** Nesting depth score (0 = scalar, 1 = flat container, etc.) */
+  size_t complexity = 0;
+
+  /** Estimated character length if rendered inline (minified + spaces) */
+  size_t estimated_inline_len = 0;
+
+  /** Number of direct children (0 for scalars) */
+  size_t child_count = 0;
+
+  /** Pre-computed: can this element be rendered inline? */
+  bool can_inline = false;
+
+  /** Is this an array where all elements have similar structure? */
+  bool is_uniform_array = false;
+
+  /** For uniform arrays of objects: the common keys */
+  std::vector<std::string> common_keys{};
+
+  /** Recommended layout mode based on analysis */
+  layout_mode recommended_layout = layout_mode::EXPANDED;
+
+  /** Child metrics for arrays and objects (in order of iteration) */
+  std::vector<element_metrics> children{};
+};
+
+/**
+ * Analyzes JSON structure to compute metrics for formatting decisions.
+ *
+ * The analyzer performs a single pass over the DOM to compute:
+ * - Complexity (nesting depth)
+ * - Estimated inline length
+ * - Array uniformity for table detection
+ *
+ * Metrics are stored hierarchically with child metrics embedded in parent metrics,
+ * enabling efficient lookup during formatting without address-based caching.
+ */
+class structure_analyzer {
+public:
+  /** Default constructor */
+  structure_analyzer() : current_opts_(nullptr) {}
+
+  /** Copy constructor - deleted since class has pointer member */
+  structure_analyzer(const structure_analyzer&) = delete;
+
+  /** Copy assignment - deleted since class has pointer member */
+  structure_analyzer& operator=(const structure_analyzer&) = delete;
+
+  /** Move constructor */
+  structure_analyzer(structure_analyzer&&) = default;
+
+  /** Move assignment */
+  structure_analyzer& operator=(structure_analyzer&&) = default;
+
+  /**
+   * Analyze a DOM element and compute metrics.
+   * @param elem The element to analyze
+   * @param opts Formatting options that affect metric computation
+   * @return Metrics for the root element (with child metrics embedded)
+   */
+  element_metrics analyze(const dom::element& elem,
+                          const fractured_json_options& opts);
+
+  /**
+   * Clear state.
+   */
+  void clear();
+
+  /**
+   * Analyze an array element directly (for standalone array formatting).
+   * @param arr The array to analyze
+   * @param opts Formatting options
+   * @return Metrics for the array
+   */
+  element_metrics analyze_array(const dom::array& arr,
+                                const fractured_json_options& opts);
+
+  /**
+   * Analyze an object element directly (for standalone object formatting).
+   * @param obj The object to analyze
+   * @param opts Formatting options
+   * @return Metrics for the object
+   */
+  element_metrics analyze_object(const dom::object& obj,
+                                 const fractured_json_options& opts);
+
+private:
+  const fractured_json_options* current_opts_ = nullptr;
+
+  /** Recursive analysis implementation */
+  element_metrics analyze_element(const dom::element& elem, size_t depth);
+
+  /** Analyze scalar values (strings, numbers, booleans, null) */
+  element_metrics analyze_scalar(const dom::element& elem);
+
+  /** Analyze an array element */
+  element_metrics analyze_array(const dom::array& arr, size_t depth);
+
+  /** Analyze an object element */
+  element_metrics analyze_object(const dom::object& obj, size_t depth);
+
+  /** Estimate inline length for a string (including quotes and escaping) */
+  size_t estimate_string_length(std::string_view s) const;
+
+  /** Estimate inline length for a number */
+  size_t estimate_number_length(double d) const;
+  size_t estimate_number_length(int64_t i) const;
+  size_t estimate_number_length(uint64_t u) const;
+
+  /**
+   * Check if an array contains uniform objects suitable for table formatting.
+   * @param arr The array to check
+   * @param common_keys Output: keys common to all objects
+   * @return true if the array is suitable for table formatting
+   */
+  bool check_array_uniformity(const dom::array& arr,
+                               std::vector<std::string>& common_keys) const;
+
+  /**
+   * Compute similarity between two objects.
+   * @return Fraction of keys that are common (0.0 to 1.0)
+   */
+  double compute_object_similarity(const dom::object& a,
+                                   const dom::object& b) const;
+
+  /**
+   * Decide the recommended layout mode based on metrics and options.
+   */
+  layout_mode decide_layout(const element_metrics& metrics,
+                            size_t depth,
+                            size_t available_width) const;
+};
+
+} // namespace internal
+} // namespace simdjson
+
+#endif // SIMDJSON_INTERNAL_JSON_STRUCTURE_ANALYZER_H

include/simdjson/lasx/begin.h

@@ -1,4 +1,11 @@
 #define SIMDJSON_IMPLEMENTATION lasx
+#include <lsxintrin.h> // This is a hack. We should not need to put this include here.
+#if SIMDJSON_CAN_ALWAYS_RUN_LASX
+// nothing needed.
+#else
+SIMDJSON_TARGET_REGION("lasx,lsx")
+#endif
+
 #include "simdjson/lasx/base.h"
 #include "simdjson/lasx/intrinsics.h"
 #include "simdjson/lasx/bitmanipulation.h"
@@ -8,3 +15,5 @@
 #include "simdjson/lasx/stringparsing_defs.h"
 
 #define SIMDJSON_SKIP_BACKSLASH_SHORT_CIRCUIT 1
+
+

include/simdjson/lasx/builder.h

@@ -0,0 +1,8 @@
+#ifndef SIMDJSON_LASX_BUILDER_H
+#define SIMDJSON_LASX_BUILDER_H
+
+#include "simdjson/lasx/begin.h"
+#include "simdjson/generic/builder/amalgamated.h"
+#include "simdjson/lasx/end.h"
+
+#endif // SIMDJSON_LASX_BUILDER_H

include/simdjson/lasx/end.h

@@ -4,3 +4,10 @@
 
 #undef SIMDJSON_SKIP_BACKSLASH_SHORT_CIRCUIT
 #undef SIMDJSON_IMPLEMENTATION
+
+
+#if SIMDJSON_CAN_ALWAYS_RUN_LASX
+// nothing needed.
+#else
+SIMDJSON_UNTARGET_REGION
+#endif

include/simdjson/lasx/intrinsics.h

@@ -5,8 +5,7 @@
 #include "simdjson/lasx/base.h"
 #endif // SIMDJSON_CONDITIONAL_INCLUDE
 
-// This should be the correct header whether
-// you use visual studio or other compilers.
+#include <lsxintrin.h>
 #include <lasxintrin.h>
 
 static_assert(sizeof(__m256i) <= simdjson::SIMDJSON_PADDING, "insufficient padding for LoongArch ASX");

include/simdjson/lasx/simd.h

@@ -303,6 +303,7 @@ namespace simd {
     static constexpr int NUM_CHUNKS = 64 / sizeof(simd8<T>);
     static_assert(NUM_CHUNKS == 2, "LASX kernel should use two registers per 64-byte block.");
     const simd8<T> chunks[NUM_CHUNKS];
+    template<int idx> simd8<uint8_t> get() const { return idx < NUM_CHUNKS ? chunks[idx] : simd8<T>(); }
 
     simd8x64(const simd8x64<T>& o) = delete; // no copy allowed
     simd8x64<T>& operator=(const simd8<T>& other) = delete; // no assignment allowed

include/simdjson/lasx/stringparsing_defs.h

@@ -61,7 +61,7 @@ simdjson_inline escaping escaping::copy_and_find(const uint8_t *src, uint8_t *ds
   simd8<bool> is_backslash = (v == '\\');
   simd8<bool> is_control = (v < 32);
   return {
-    (is_backslash | is_quote | is_control).to_bitmask()
+    static_cast<uint64_t>((is_backslash | is_quote | is_control).to_bitmask())
   };
 }
 

include/simdjson/lsx/builder.h

@@ -0,0 +1,8 @@
+#ifndef SIMDJSON_LSX_BUILDER_H
+#define SIMDJSON_LSX_BUILDER_H
+
+#include "simdjson/lsx/begin.h"
+#include "simdjson/generic/builder/amalgamated.h"
+#include "simdjson/lsx/end.h"
+
+#endif // SIMDJSON_LSX_BUILDER_H

include/simdjson/lsx/intrinsics.h

@@ -5,8 +5,6 @@
 #include "simdjson/lsx/base.h"
 #endif // SIMDJSON_CONDITIONAL_INCLUDE
 
-// This should be the correct header whether
-// you use visual studio or other compilers.
 #include <lsxintrin.h>
 
 static_assert(sizeof(__m128i) <= simdjson::SIMDJSON_PADDING, "insufficient padding for LoongArch SX");

include/simdjson/lsx/simd.h

@@ -260,6 +260,7 @@ namespace simd {
     static constexpr int NUM_CHUNKS = 64 / sizeof(simd8<T>);
     static_assert(NUM_CHUNKS == 4, "LSX kernel should use four registers per 64-byte block.");
     const simd8<T> chunks[NUM_CHUNKS];
+    template<int idx> simd8<uint8_t> get() const { return idx < NUM_CHUNKS ? chunks[idx] : simd8<T>(); }
 
     simd8x64(const simd8x64<T>& o) = delete; // no copy allowed
     simd8x64<T>& operator=(const simd8<T>& other) = delete; // no assignment allowed

include/simdjson/padded_string-inl.h

@@ -126,6 +126,33 @@ inline const char *padded_string::data() const noexcept { return data_ptr; }
 
 inline char *padded_string::data() noexcept { return data_ptr; }
 
+inline bool padded_string::append(const char *data, size_t length) noexcept {
+  if (length == 0) {
+    return true; // Nothing to append
+  }
+  size_t new_size = viable_size + length;
+  if (new_size < viable_size) {
+    // Overflow, cannot append
+    return false;
+  }
+  char *new_data_ptr = internal::allocate_padded_buffer(new_size);
+  if (new_data_ptr == nullptr) {
+    // Allocation failed, cannot append
+    return false;
+  }
+  // Copy existing data
+  if (viable_size > 0) {
+    std::memcpy(new_data_ptr, data_ptr, viable_size);
+  }
+  // Copy new data
+  std::memcpy(new_data_ptr + viable_size, data, length);
+  // Update
+  delete[] data_ptr;
+  data_ptr = new_data_ptr;
+  viable_size = new_size;
+  return true;
+}
+
 inline padded_string::operator std::string_view() const simdjson_lifetime_bound { return std::string_view(data(), length()); }
 
 inline padded_string::operator padded_string_view() const noexcept simdjson_lifetime_bound {
@@ -242,6 +269,103 @@ inline simdjson_result<padded_string> padded_string::load(std::wstring_view file
 }
 #endif
 
+// padded_string_builder implementations
+
+inline padded_string_builder::padded_string_builder() noexcept = default;
+
+inline padded_string_builder::padded_string_builder(size_t new_capacity) noexcept {
+  if (new_capacity > 0) {
+    data = internal::allocate_padded_buffer(new_capacity);
+    if (data != nullptr) {
+      this->capacity = new_capacity;
+    }
+  }
+}
+
+inline padded_string_builder::padded_string_builder(padded_string_builder &&o) noexcept
+    : size(o.size), capacity(o.capacity), data(o.data) {
+  o.size = 0;
+  o.capacity = 0;
+  o.data = nullptr;
+}
+
+inline padded_string_builder &padded_string_builder::operator=(padded_string_builder &&o) noexcept {
+  if (this != &o) {
+    delete[] data;
+    size = o.size;
+    capacity = o.capacity;
+    data = o.data;
+    o.size = 0;
+    o.capacity = 0;
+    o.data = nullptr;
+  }
+  return *this;
+}
+
+inline padded_string_builder::~padded_string_builder() noexcept {
+  delete[] data;
+}
+
+inline bool padded_string_builder::append(const char *newdata, size_t length) noexcept {
+  if (length == 0) {
+    return true;
+  }
+  if (!reserve(length)) {
+    return false;
+  }
+  std::memcpy(data + size, newdata, length);
+  size += length;
+  return true;
+}
+
+inline bool padded_string_builder::append(std::string_view sv) noexcept {
+  return append(sv.data(), sv.size());
+}
+
+inline size_t padded_string_builder::length() const noexcept {
+  return size;
+}
+
+inline padded_string padded_string_builder::build() const noexcept {
+  return padded_string(data, size);
+}
+
+inline padded_string padded_string_builder::convert() noexcept {
+  padded_string result{};
+  result.data_ptr = data;
+  result.viable_size = size;
+  data = nullptr;
+  size = 0;
+  capacity = 0;
+  return result;
+}
+
+inline bool padded_string_builder::reserve(size_t additional) noexcept {
+  size_t needed = size + additional;
+  if (needed <= capacity) {
+    return true;
+  }
+  size_t new_capacity = needed;
+  // We are going to grow the capacity exponentially to avoid
+  // repeated allocations.
+  if (new_capacity < 4096) {
+    new_capacity *= 2;
+  } else {
+    new_capacity += new_capacity/2; // grow by 1.5x
+  }
+  char *new_data = internal::allocate_padded_buffer(new_capacity);
+  if (new_data == nullptr) {
+    return false; // Allocation failed
+  }
+  if (size > 0) {
+    std::memcpy(new_data, data, size);
+  }
+  delete[] data;
+  data = new_data;
+  capacity = new_capacity;
+  return true;
+}
+
 } // namespace simdjson
 
 inline simdjson::padded_string operator ""_padded(const char *str, size_t len) {