diff --git a/.github/workflows/ubuntu20-checkperf.yml b/.github/workflows/ubuntu20-checkperf.yml
index 9c29bdf1b..b5e4a38f8 100644
--- a/.github/workflows/ubuntu20-checkperf.yml
+++ b/.github/workflows/ubuntu20-checkperf.yml
@@ -24,6 +24,6 @@ jobs:
         run: |
           mkdir build &&
           cd build &&
-          cmake  -DSIMDJSON_GOOGLE_BENCHMARKS=ON -DSIMDJSON_BUILD_STATIC=ON -DCMAKE_INSTALL_PREFIX:PATH=destination ..  &&
+          cmake  -DCMAKE_CXX_FLAGS="-Werror=old-style-cast -pedantic -Wpedantic" -DSIMDJSON_GOOGLE_BENCHMARKS=ON -DSIMDJSON_BUILD_STATIC=ON -DCMAKE_INSTALL_PREFIX:PATH=destination ..  &&
           cmake --build . --target checkperf  &&
           ctest --output-on-failure -R checkperf 
diff --git a/benchmark/benchmarker.h b/benchmark/benchmarker.h
index bb9c42a29..ccbc5b631 100644
--- a/benchmark/benchmarker.h
+++ b/benchmark/benchmarker.h
@@ -321,7 +321,7 @@ struct benchmarker {
     allocate_stage << allocate_count;
     // Run it once to get hot buffers
     if(hotbuffers) {
-      auto result = parser.parse((const uint8_t *)json.data(), json.size());
+      auto result = parser.parse(reinterpret_cast<const uint8_t *>(json.data()), json.size());
       if (result.error()) {
         exit_error(string("Failed to parse ") + filename + string(":") + error_message(result.error()));
       }
@@ -331,7 +331,7 @@ struct benchmarker {
 
     // Stage 1 (find structurals)
     collector.start();
-    error = parser.implementation->stage1((const uint8_t *)json.data(), json.size(), false);
+    error = parser.implementation->stage1(reinterpret_cast<const uint8_t *>(json.data()), json.size(), false);
     event_count stage1_count = collector.end();
     stage1 << stage1_count;
     if (error) {
@@ -367,7 +367,7 @@ struct benchmarker {
 
   void run_loop(size_t iterations) {
     dom::parser parser;
-    auto firstresult = parser.parse((const uint8_t *)json.data(), json.size());
+    auto firstresult = parser.parse(reinterpret_cast<const uint8_t *>(json.data()), json.size());
     if (firstresult.error()) {
       exit_error(string("Failed to parse ") + filename + string(":") + error_message(firstresult.error()));
     }
@@ -375,7 +375,7 @@ struct benchmarker {
     collector.start();
     // some users want something closer to "number of documents per second"
     for(size_t i = 0; i < iterations; i++) {
-      auto result = parser.parse((const uint8_t *)json.data(), json.size());
+      auto result = parser.parse(reinterpret_cast<const uint8_t *>(json.data()), json.size());
       if (result.error()) {
         exit_error(string("Failed to parse ") + filename + string(":") + error_message(result.error()));
       }
@@ -446,7 +446,7 @@ struct benchmarker {
 
   void print(bool tabbed_output) const {
     if (tabbed_output) {
-      char* filename_copy = (char*)malloc(strlen(filename)+1);
+      char* filename_copy = reinterpret_cast<char*>(malloc(strlen(filename)+1));
       SIMDJSON_PUSH_DISABLE_WARNINGS
       SIMDJSON_DISABLE_DEPRECATED_WARNING // Validated CRT_SECURE safe here
       strcpy(filename_copy, filename);
diff --git a/include/simdjson/arm64/simd.h b/include/simdjson/arm64/simd.h
index 0a8948962..df4249d00 100644
--- a/include/simdjson/arm64/simd.h
+++ b/include/simdjson/arm64/simd.h
@@ -115,9 +115,9 @@ simdjson_really_inline int8x16_t make_int8x16_t(int8_t x1,  int8_t x2,  int8_t x
     simdjson_really_inline simd8<T> operator^(const simd8<T> other) const { return veorq_u8(*this, other); }
     simdjson_really_inline simd8<T> bit_andnot(const simd8<T> other) const { return vbicq_u8(*this, other); }
     simdjson_really_inline simd8<T> operator~() const { return *this ^ 0xFFu; }
-    simdjson_really_inline simd8<T>& operator|=(const simd8<T> other) { auto this_cast = (simd8<T>*)this; *this_cast = *this_cast | other; return *this_cast; }
-    simdjson_really_inline simd8<T>& operator&=(const simd8<T> other) { auto this_cast = (simd8<T>*)this; *this_cast = *this_cast & other; return *this_cast; }
-    simdjson_really_inline simd8<T>& operator^=(const simd8<T> other) { auto this_cast = (simd8<T>*)this; *this_cast = *this_cast ^ other; return *this_cast; }
+    simdjson_really_inline simd8<T>& operator|=(const simd8<T> other) { auto this_cast = static_cast<simd8<T>*>(this); *this_cast = *this_cast | other; return *this_cast; }
+    simdjson_really_inline simd8<T>& operator&=(const simd8<T> other) { auto this_cast = static_cast<simd8<T>*>(this); *this_cast = *this_cast & other; return *this_cast; }
+    simdjson_really_inline simd8<T>& operator^=(const simd8<T> other) { auto this_cast = static_cast<simd8<T>*>(this); *this_cast = *this_cast ^ other; return *this_cast; }
 
     simdjson_really_inline Mask operator==(const simd8<T> other) const { return vceqq_u8(*this, other); }
 
@@ -284,9 +284,9 @@ simdjson_really_inline int8x16_t make_int8x16_t(int8_t x1,  int8_t x2,  int8_t x
       // only the first pop1 bytes from the first 8 bytes, and then
       // it fills in with the bytes from the second 8 bytes + some filling
       // at the end.
-      uint8x16_t compactmask = vld1q_u8((const uint8_t *)(pshufb_combine_table + pop1 * 8));
+      uint8x16_t compactmask = vld1q_u8(reinterpret_cast<const uint8_t *>(pshufb_combine_table + pop1 * 8));
       uint8x16_t answer = vqtbl1q_u8(pruned, compactmask);
-      vst1q_u8((uint8_t*) output, answer);
+      vst1q_u8(reinterpret_cast<uint8_t*>(output), answer);
     }
 
     template<typename L>
diff --git a/include/simdjson/generic/stringparsing.h b/include/simdjson/generic/stringparsing.h
index 0f772d0db..7bc6d4796 100644
--- a/include/simdjson/generic/stringparsing.h
+++ b/include/simdjson/generic/stringparsing.h
@@ -127,7 +127,7 @@ simdjson_unused simdjson_warn_unused simdjson_really_inline error_code parse_str
   if (*(src++) != '"') { return STRING_ERROR; }
   auto end = stringparsing::parse_string(src, current_string_buf_loc);
   if (!end) { return STRING_ERROR; }
-  s = std::string_view((const char *)current_string_buf_loc, end-current_string_buf_loc);
+  s = std::string_view(reinterpret_cast<const char *>(current_string_buf_loc), end-current_string_buf_loc);
   current_string_buf_loc = end;
   return SUCCESS;
 }
diff --git a/include/simdjson/ppc64/simd.h b/include/simdjson/ppc64/simd.h
index 51a0bd9ea..f8683bc87 100644
--- a/include/simdjson/ppc64/simd.h
+++ b/include/simdjson/ppc64/simd.h
@@ -42,17 +42,17 @@ template <typename Child> struct base {
     return vec_andc(this->value, (__m128i)other);
   }
   simdjson_really_inline Child &operator|=(const Child other) {
-    auto this_cast = (Child *)this;
+    auto this_cast = static_cast<Child*>(this);
     *this_cast = *this_cast | other;
     return *this_cast;
   }
   simdjson_really_inline Child &operator&=(const Child other) {
-    auto this_cast = (Child *)this;
+    auto this_cast = static_cast<Child*>(this);
     *this_cast = *this_cast & other;
     return *this_cast;
   }
   simdjson_really_inline Child &operator^=(const Child other) {
-    auto this_cast = (Child *)this;
+    auto this_cast = static_cast<Child*>(this);
     *this_cast = *this_cast ^ other;
     return *this_cast;
   }
@@ -131,7 +131,7 @@ template <typename T> struct base8_numeric : base8<T> {
   }
   static simdjson_really_inline simd8<T> zero() { return splat(0); }
   static simdjson_really_inline simd8<T> load(const T values[16]) {
-    return (__m128i)(vec_vsx_ld(0, (const uint8_t *)values));
+    return (__m128i)(vec_vsx_ld(0, reinterpret_cast<const uint8_t *>(values)));
   }
   // Repeat 16 values as many times as necessary (usually for lookup tables)
   static simdjson_really_inline simd8<T> repeat_16(T v0, T v1, T v2, T v3, T v4,
@@ -163,11 +163,11 @@ template <typename T> struct base8_numeric : base8<T> {
   }
   simdjson_really_inline simd8<T> &operator+=(const simd8<T> other) {
     *this = *this + other;
-    return *(simd8<T> *)this;
+    return *static_cast<simd8<T> *>(this);
   }
   simdjson_really_inline simd8<T> &operator-=(const simd8<T> other) {
     *this = *this - other;
-    return *(simd8<T> *)this;
+    return *static_cast<simd8<T> *>(this);
   }
 
   // Perform a lookup assuming the value is between 0 and 16 (undefined behavior
@@ -217,9 +217,9 @@ template <typename T> struct base8_numeric : base8<T> {
     // it fills in with the bytes from the second 8 bytes + some filling
     // at the end.
     __m128i compactmask =
-        vec_vsx_ld(0, (const uint8_t *)(pshufb_combine_table + pop1 * 8));
+        vec_vsx_ld(0, reinterpret_cast<const uint8_t *>(pshufb_combine_table + pop1 * 8));
     __m128i answer = vec_perm(pruned, (__m128i)vec_splats(0), compactmask);
-    vec_vsx_st(answer, 0, (__m128i *)(output));
+    vec_vsx_st(answer, 0, reinterpret_cast<__m128i *>(output));
   }
 
   template <typename L>