diff --git a/benchmark/bench_ondemand.cpp b/benchmark/bench_ondemand.cpp
index 429407faa..bb1a2c428 100644
--- a/benchmark/bench_ondemand.cpp
+++ b/benchmark/bench_ondemand.cpp
@@ -7,10 +7,6 @@ SIMDJSON_PUSH_DISABLE_ALL_WARNINGS
 #include <benchmark/benchmark.h>
 SIMDJSON_POP_DISABLE_WARNINGS
 
-#if SIMDJSON_IMPLEMENTATION_HASWELL
-#include "simdjson/haswell/begin.h"
-#endif // SIMDJSON_IMPLEMENTATION_HASWELL
-
 #include "partial_tweets/ondemand.h"
 #include "partial_tweets/iter.h"
 #include "partial_tweets/dom.h"
@@ -24,7 +20,3 @@ SIMDJSON_POP_DISABLE_WARNINGS
 #include "kostya/dom.h"
 
 BENCHMARK_MAIN();
-
-#if SIMDJSON_IMPLEMENTATION_HASWELL
-#include "simdjson/haswell/end.h"
-#endif // SIMDJSON_IMPLEMENTATION_HASWELL
diff --git a/benchmark/bench_sax.cpp b/benchmark/bench_sax.cpp
index e1434172c..2a40898ab 100644
--- a/benchmark/bench_sax.cpp
+++ b/benchmark/bench_sax.cpp
@@ -8,16 +8,7 @@ SIMDJSON_PUSH_DISABLE_ALL_WARNINGS
 #include <benchmark/benchmark.h>
 SIMDJSON_POP_DISABLE_WARNINGS
 
-
-#if SIMDJSON_IMPLEMENTATION_HASWELL
-#include "simdjson/haswell/begin.h"
-#endif // SIMDJSON_IMPLEMENTATION_HASWELL
-
 #include "partial_tweets/sax.h"
 #include "largerandom/sax.h"
 
 BENCHMARK_MAIN();
-
-#if SIMDJSON_IMPLEMENTATION_HASWELL
-#include "simdjson/haswell/end.h"
-#endif // SIMDJSON_IMPLEMENTATION_HASWELL
diff --git a/benchmark/kostya/iter.h b/benchmark/kostya/iter.h
index cacf1b478..92ad5048d 100644
--- a/benchmark/kostya/iter.h
+++ b/benchmark/kostya/iter.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "kostya.h"
@@ -8,7 +7,7 @@
 namespace kostya {
 
 using namespace simdjson;
-using namespace simdjson::SIMDJSON_IMPLEMENTATION;
+using namespace simdjson::builtin;
 
 class Iter {
 public:
@@ -21,12 +20,12 @@ private:
   ondemand::parser parser{};
   std::vector<my_point> container{};
 
-  simdjson_really_inline simdjson_result<double> first_double(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter, const char *key) {
+  simdjson_really_inline simdjson_result<double> first_double(ondemand::json_iterator &iter, const char *key) {
     if (!iter.start_object() || ondemand::raw_json_string(iter.field_key()) != key || iter.field_value()) { throw "Invalid field"; }
     return iter.get_double();
   }
 
-  simdjson_really_inline simdjson_result<double> next_double(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter, const char *key) {
+  simdjson_really_inline simdjson_result<double> next_double(ondemand::json_iterator &iter, const char *key) {
     if (!iter.has_next_field() || ondemand::raw_json_string(iter.field_key()) != key || iter.field_value()) { throw "Invalid field"; }
     return iter.get_double();
   }
@@ -95,4 +94,3 @@ BENCHMARK_TEMPLATE(KostyaSum, Iter);
 } // namespace kostya
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/kostya/ondemand.h b/benchmark/kostya/ondemand.h
index b9ebbdecb..b0fce18d5 100644
--- a/benchmark/kostya/ondemand.h
+++ b/benchmark/kostya/ondemand.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "kostya.h"
@@ -8,7 +7,7 @@
 namespace kostya {
 
 using namespace simdjson;
-using namespace simdjson::SIMDJSON_IMPLEMENTATION;
+using namespace simdjson::builtin;
 
 class OnDemand {
 public:
@@ -75,4 +74,3 @@ BENCHMARK_TEMPLATE(KostyaSum, OnDemand);
 } // namespace kostya
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/largerandom/iter.h b/benchmark/largerandom/iter.h
index 5c81bac2b..58580999e 100644
--- a/benchmark/largerandom/iter.h
+++ b/benchmark/largerandom/iter.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "largerandom.h"
@@ -8,7 +7,7 @@
 namespace largerandom {
 
 using namespace simdjson;
-using namespace simdjson::SIMDJSON_IMPLEMENTATION;
+using namespace simdjson::builtin;
 
 class Iter {
 public:
@@ -21,12 +20,12 @@ private:
   ondemand::parser parser{};
   std::vector<my_point> container{};
 
-  simdjson_really_inline double first_double(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter) {
+  simdjson_really_inline double first_double(ondemand::json_iterator &iter) {
     if (iter.start_object().error() || iter.field_key().error() || iter.field_value()) { throw "Invalid field"; }
     return iter.get_double();
   }
 
-  simdjson_really_inline double next_double(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter) {
+  simdjson_really_inline double next_double(ondemand::json_iterator &iter) {
     if (!iter.has_next_field() || iter.field_key().error() || iter.field_value()) { throw "Invalid field"; }
     return iter.get_double();
   }
@@ -91,4 +90,3 @@ BENCHMARK_TEMPLATE(LargeRandomSum, Iter);
 } // namespace largerandom
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/largerandom/ondemand.h b/benchmark/largerandom/ondemand.h
index c228fa53d..12dfa5473 100644
--- a/benchmark/largerandom/ondemand.h
+++ b/benchmark/largerandom/ondemand.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "largerandom.h"
@@ -8,7 +7,7 @@
 namespace largerandom {
 
 using namespace simdjson;
-using namespace simdjson::SIMDJSON_IMPLEMENTATION;
+using namespace simdjson::builtin;
 
 class OnDemand {
 public:
@@ -72,4 +71,3 @@ BENCHMARK_TEMPLATE(LargeRandomSum, OnDemand);
 } // namespace largerandom
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/largerandom/sax.h b/benchmark/largerandom/sax.h
index 49f3d3a8f..b9653a0c5 100644
--- a/benchmark/largerandom/sax.h
+++ b/benchmark/largerandom/sax.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "largerandom.h"
@@ -8,8 +7,8 @@
 namespace largerandom {
 
 using namespace simdjson;
-using namespace SIMDJSON_IMPLEMENTATION;
-using namespace SIMDJSON_IMPLEMENTATION::stage2;
+using namespace simdjson::builtin;
+using namespace simdjson::builtin::stage2;
 
 class Sax {
 public:
@@ -28,8 +27,8 @@ private:
 };
 
 using namespace simdjson;
-using namespace SIMDJSON_IMPLEMENTATION;
-using namespace SIMDJSON_IMPLEMENTATION::stage2;
+using namespace simdjson::builtin;
+using namespace simdjson::builtin::stage2;
 struct sax_point_reader_visitor {
 public:
   std::vector<my_point> &points;
@@ -123,4 +122,3 @@ BENCHMARK_TEMPLATE(LargeRandom, Sax);
 } // namespace largerandom
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/partial_tweets/iter.h b/benchmark/partial_tweets/iter.h
index 780c3a2d8..5b69b44f2 100644
--- a/benchmark/partial_tweets/iter.h
+++ b/benchmark/partial_tweets/iter.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "partial_tweets.h"
@@ -8,7 +7,7 @@
 namespace partial_tweets {
 
 using namespace simdjson;
-using namespace simdjson::SIMDJSON_IMPLEMENTATION;
+using namespace simdjson::builtin;
 
 class Iter {
 public:
@@ -92,4 +91,3 @@ BENCHMARK_TEMPLATE(PartialTweets, Iter);
 } // namespace partial_tweets
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/partial_tweets/ondemand.h b/benchmark/partial_tweets/ondemand.h
index 08d8c1501..8003c42cc 100644
--- a/benchmark/partial_tweets/ondemand.h
+++ b/benchmark/partial_tweets/ondemand.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 #if SIMDJSON_EXCEPTIONS
 
 #include "partial_tweets.h"
@@ -8,7 +7,7 @@
 namespace partial_tweets {
 
 using namespace simdjson;
-using namespace simdjson::SIMDJSON_IMPLEMENTATION;
+using namespace simdjson::builtin;
 
 class OnDemand {
 public:
@@ -57,4 +56,3 @@ BENCHMARK_TEMPLATE(PartialTweets, OnDemand);
 } // namespace partial_tweets
 
 #endif // SIMDJSON_EXCEPTIONS
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/partial_tweets/sax.h b/benchmark/partial_tweets/sax.h
index e3dde8aab..a5e8af3a7 100644
--- a/benchmark/partial_tweets/sax.h
+++ b/benchmark/partial_tweets/sax.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#ifdef SIMDJSON_IMPLEMENTATION
 
 #include "partial_tweets.h"
 #include "sax_tweet_reader_visitor.h"
@@ -8,8 +7,8 @@
 namespace partial_tweets {
 
 using namespace simdjson;
-using namespace SIMDJSON_IMPLEMENTATION;
-using namespace SIMDJSON_IMPLEMENTATION::stage2;
+using namespace simdjson::builtin;
+using namespace simdjson::builtin::stage2;
 
 class Sax {
 public:
@@ -68,4 +67,3 @@ BENCHMARK_TEMPLATE(PartialTweets, Sax);
 
 } // namespace partial_tweets
 
-#endif // SIMDJSON_IMPLEMENTATION
diff --git a/benchmark/partial_tweets/sax_tweet_reader_visitor.h b/benchmark/partial_tweets/sax_tweet_reader_visitor.h
index ca99795cb..ea1148448 100644
--- a/benchmark/partial_tweets/sax_tweet_reader_visitor.h
+++ b/benchmark/partial_tweets/sax_tweet_reader_visitor.h
@@ -7,8 +7,8 @@
 namespace partial_tweets {
 
 using namespace simdjson;
-using namespace SIMDJSON_IMPLEMENTATION;
-using namespace SIMDJSON_IMPLEMENTATION::stage2;
+using namespace simdjson::builtin;
+using namespace simdjson::builtin::stage2;
 
 struct sax_tweet_reader_visitor {
 public: