diff --git a/.github/workflows/Build.yml b/.github/workflows/Build.yml
index 71ee5631b5..7d59386a32 100644
--- a/.github/workflows/Build.yml
+++ b/.github/workflows/Build.yml
@@ -13,6 +13,29 @@ env:
   kphp_build_dir: /home/kitten/kphp/build
 
 jobs:
+  clang-format:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v3
+      - name: Add LLVM GPG key
+        run: |
+          sudo wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo gpg --dearmor -o /etc/apt/trusted.gpg.d/llvm.gpg
+        shell: bash
+
+      - name: Add LLVM repository
+        run: |
+          echo "deb [signed-by=/etc/apt/trusted.gpg.d/llvm.gpg] http://apt.llvm.org/jammy/ llvm-toolchain-jammy-18 main" | sudo tee /etc/apt/sources.list.d/llvm.list
+        shell: bash
+
+      - name: Update and Install LLVM
+        run: |
+          sudo apt update
+          sudo apt install -y clang-format-18
+        shell: bash
+      - name: debug
+        run: which clang-format-18
+      - name: Run clang-format
+        run: find ./runtime-light/ -iname '*.h' -o -iname '*.cpp' | xargs clang-format-18 --dry-run -Werror
   build-linux:
     runs-on: ubuntu-latest
     strategy:
diff --git a/common/dl-utils-lite.cpp b/common/dl-utils-lite.cpp
index 8648274d6c..8315eaa5b2 100644
--- a/common/dl-utils-lite.cpp
+++ b/common/dl-utils-lite.cpp
@@ -22,6 +22,7 @@
 #include <time.h>
 #include <unistd.h>
 #include <dirent.h>
+#include <tuple>
 
 #include "common/server/crash-dump.h"
 #include "common/stats/provider.h"
@@ -49,9 +50,9 @@ double dl_time() {
 }
 
 void dl_print_backtrace(void **trace, int trace_size) {
-  write (2, "\n------- Stack Backtrace -------\n", 33);
+  std::ignore = write (2, "\n------- Stack Backtrace -------\n", 33);
   backtrace_symbols_fd (trace, trace_size, 2);
-  write (2, "-------------------------------\n", 32);
+  std::ignore = write (2, "-------------------------------\n", 32);
 }
 
 void dl_print_backtrace() {
@@ -71,7 +72,7 @@ void dl_print_backtrace_gdb() {
     name_buf[res] = 0;
     int child_pid = fork();
     if (child_pid < 0) {
-      write (2, "Can't fork() to run gdb\n", 24);
+      std::ignore = write (2, "Can't fork() to run gdb\n", 24);
       _exit (0);
     }
     if (!child_pid) {
@@ -83,7 +84,7 @@ void dl_print_backtrace_gdb() {
       waitpid (child_pid, nullptr, 0);
     }
   } else {
-    write (2, "can't get name of executable file to pass to gdb\n", 49);
+    std::ignore = write (2, "can't get name of executable file to pass to gdb\n", 49);
   }
 }
 
diff --git a/runtime-light/header.h b/runtime-light/header.h
index 5bae9daf93..d513554a0f 100644
--- a/runtime-light/header.h
+++ b/runtime-light/header.h
@@ -107,8 +107,7 @@ struct PlatformCtx {
    * `stream_d` will be assigned `0`.
    * however `stream_d=0` itself is not an error marker
    */
-  enum OpenStreamResult (*open)(size_t name_len, const char *name,
-                                uint64_t *stream_d);
+  enum OpenStreamResult (*open)(size_t name_len, const char *name, uint64_t *stream_d);
   /*
    * If the write or read status is `Blocked` - then the platform ensures that
    * the component receives this `stream_d` via `take_update` when the status is
@@ -118,8 +117,7 @@ struct PlatformCtx {
    * `new_status` will be assigned as
    * `{.read_status = 0, .write_status = 0, .please_shutdown = 0}`.
    */
-  enum GetStatusResult (*get_stream_status)(uint64_t stream_d,
-                                            struct StreamStatus *new_status);
+  enum GetStatusResult (*get_stream_status)(uint64_t stream_d, struct StreamStatus *new_status);
   /*
    * Return processed bytes (written or read).
    * Guaranteed to return `0` if  the stream is `Closed`, `Blocked` or
@@ -190,8 +188,7 @@ struct PlatformCtx {
    *
    * `deadline` will be assigned `0` if `timer_d` invalid
    */
-  enum TimerStatus (*get_timer_status)(uint64_t timer_d,
-                                       struct TimePoint *deadline);
+  enum TimerStatus (*get_timer_status)(uint64_t timer_d, struct TimePoint *deadline);
   /*
    * Return: `bool`.
    * If `True`: the update was successfully received.
@@ -262,15 +259,11 @@ struct ImageInfo {
 };
 
 // Every image should provide these symbols
-enum PollStatus vk_k2_poll(const struct ImageState *image_state,
-                           const struct PlatformCtx *pt_ctx,
-                           struct ComponentState *component_ctx);
+enum PollStatus vk_k2_poll(const struct ImageState *image_state, const struct PlatformCtx *pt_ctx, struct ComponentState *component_ctx);
 
 // platform_ctx without IO stuff (nullptr instead io-functions)
 // for now, returning nullptr will indicate error
-struct ComponentState *
-vk_k2_create_component_state(const struct ImageState *image_state,
-                             const struct PlatformCtx *pt_ctx);
+struct ComponentState *vk_k2_create_component_state(const struct ImageState *image_state, const struct PlatformCtx *pt_ctx);
 
 // platform_ctx without IO stuff (nullptr instead io-functions)
 // for now, returning nullptr will indicate error
diff --git a/runtime-light/stdlib/rpc/rpc-buffer.h b/runtime-light/stdlib/rpc/rpc-buffer.h
index 3d8f0b0f3e..64bb74ea0b 100644
--- a/runtime-light/stdlib/rpc/rpc-buffer.h
+++ b/runtime-light/stdlib/rpc/rpc-buffer.h
@@ -43,7 +43,7 @@ class RpcBuffer : private vk::not_copyable {
   }
 
   void reset(size_t pos) noexcept {
-    php_assert(pos >= 0 && pos <= size());
+    php_assert(pos > 0 && pos <= size());
     m_pos = pos;
     m_remaining = size() - m_pos;
   }
diff --git a/runtime-light/tl/tl-core.h b/runtime-light/tl/tl-core.h
index ba179db59c..b5414300cb 100644
--- a/runtime-light/tl/tl-core.h
+++ b/runtime-light/tl/tl-core.h
@@ -74,8 +74,7 @@ class TLBuffer : private vk::not_copyable {
   }
 
   template<standard_layout T, standard_layout U>
-    requires std::convertible_to<U, T>
-  void store_trivial(const U &t) noexcept {
+  requires std::convertible_to<U, T> void store_trivial(const U &t) noexcept {
     // Here we rely on that endianness of architecture is Little Endian
     store_bytes(reinterpret_cast<const char *>(std::addressof(t)), sizeof(T));
   }
diff --git a/runtime-light/utils/json-functions.cpp b/runtime-light/utils/json-functions.cpp
index 5fde8e0723..58d88c05a2 100644
--- a/runtime-light/utils/json-functions.cpp
+++ b/runtime-light/utils/json-functions.cpp
@@ -7,13 +7,13 @@
 #include "common/algorithms/find.h"
 #include "runtime-light/component/component.h"
 //
-//#include "runtime/string_functions.h"
+// #include "runtime/string_functions.h"
 
 // note: json-functions.cpp is used for non-typed json implementation: for json_encode() and json_decode()
 // for classes, e.g. `JsonEncoder::encode(new A)`, see json-writer.cpp and from/to visitors
 namespace {
 
-void json_append_one_char(unsigned int c, string_buffer & sb) noexcept {
+void json_append_one_char(unsigned int c, string_buffer &sb) noexcept {
   sb.append_char('\\');
   sb.append_char('u');
   sb.append_char("0123456789abcdef"[c >> 12]);
@@ -22,7 +22,7 @@ void json_append_one_char(unsigned int c, string_buffer & sb) noexcept {
   sb.append_char("0123456789abcdef"[c & 15]);
 }
 
-bool json_append_char(unsigned int c, string_buffer & sb) noexcept {
+bool json_append_char(unsigned int c, string_buffer &sb) noexcept {
   if (c < 0x10000) {
     if (0xD7FF < c && c < 0xE000) {
       return false;
@@ -39,8 +39,7 @@ bool json_append_char(unsigned int c, string_buffer & sb) noexcept {
   return false;
 }
 
-
-bool do_json_encode_string_php(const JsonPath &json_path, const char *s, int len, int64_t options, string_buffer & sb) noexcept {
+bool do_json_encode_string_php(const JsonPath &json_path, const char *s, int len, int64_t options, string_buffer &sb) noexcept {
   int begin_pos = sb.size();
   if (options & JSON_UNESCAPED_UNICODE) {
     sb.reserve(2 * len + 2);
@@ -178,7 +177,7 @@ string JsonPath::to_string() const {
   }
   unsigned num_parts = std::clamp(depth, 0U, static_cast<unsigned>(arr.size()));
   string result;
-  result.reserve_at_least((num_parts+1) * 8);
+  result.reserve_at_least((num_parts + 1) * 8);
   result.push_back('/');
   for (unsigned i = 0; i < num_parts; i++) {
     const char *key = arr[i];
@@ -200,13 +199,12 @@ string JsonPath::to_string() const {
 
 namespace impl_ {
 
-JsonEncoder::JsonEncoder(int64_t options, bool simple_encode, const char *json_obj_magic_key) noexcept:
-  options_(options),
-  simple_encode_(simple_encode),
-  json_obj_magic_key_(json_obj_magic_key) {
-}
+JsonEncoder::JsonEncoder(int64_t options, bool simple_encode, const char *json_obj_magic_key) noexcept
+  : options_(options)
+  , simple_encode_(simple_encode)
+  , json_obj_magic_key_(json_obj_magic_key) {}
 
-bool JsonEncoder::encode(bool b, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(bool b, string_buffer &sb) noexcept {
   if (b) {
     sb.append("true", 4);
   } else {
@@ -215,17 +213,17 @@ bool JsonEncoder::encode(bool b, string_buffer & sb) noexcept {
   return true;
 }
 
-bool JsonEncoder::encode_null(string_buffer & sb) const noexcept {
+bool JsonEncoder::encode_null(string_buffer &sb) const noexcept {
   sb.append("null", 4);
   return true;
 }
 
-bool JsonEncoder::encode(int64_t i, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(int64_t i, string_buffer &sb) noexcept {
   sb << i;
   return true;
 }
 
-bool JsonEncoder::encode(double d, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(double d, string_buffer &sb) noexcept {
   if (vk::any_of_equal(std::fpclassify(d), FP_INFINITE, FP_NAN)) {
     php_warning("%s: strange double %lf in function json_encode", json_path_.to_string().c_str(), d);
     if (options_ & JSON_PARTIAL_OUTPUT_ON_ERROR) {
@@ -234,17 +232,17 @@ bool JsonEncoder::encode(double d, string_buffer & sb) noexcept {
       return false;
     }
   } else {
-    //todo:k2 implement f$number_format
-    sb << /*(simple_encode_ ? f$number_format(d, 6, string{"."}, string{}) : */ string{d}/*)*/;
+    // todo:k2 implement f$number_format
+    sb << /*(simple_encode_ ? f$number_format(d, 6, string{"."}, string{}) : */ string{d} /*)*/;
   }
   return true;
 }
 
-bool JsonEncoder::encode(const string &s, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(const string &s, string_buffer &sb) noexcept {
   return do_json_encode_string_php(json_path_, s.c_str(), s.size(), options_, sb);
 }
 
-bool JsonEncoder::encode(const mixed &v, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(const mixed &v, string_buffer &sb) noexcept {
   switch (v.get_type()) {
     case mixed::type::NUL:
       return encode_null(sb);
@@ -280,29 +278,22 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
   json_skip_blanks(s, i);
   switch (s[i]) {
     case 'n':
-      if (s[i + 1] == 'u' &&
-          s[i + 2] == 'l' &&
-          s[i + 3] == 'l') {
+      if (s[i + 1] == 'u' && s[i + 2] == 'l' && s[i + 3] == 'l') {
         i += 4;
         return true;
       }
       break;
     case 't':
-      if (s[i + 1] == 'r' &&
-          s[i + 2] == 'u' &&
-          s[i + 3] == 'e') {
+      if (s[i + 1] == 'r' && s[i + 2] == 'u' && s[i + 3] == 'e') {
         i += 4;
-        new(&v) mixed(true);
+        new (&v) mixed(true);
         return true;
       }
       break;
     case 'f':
-      if (s[i + 1] == 'a' &&
-          s[i + 2] == 'l' &&
-          s[i + 3] == 's' &&
-          s[i + 4] == 'e') {
+      if (s[i + 1] == 'a' && s[i + 2] == 'l' && s[i + 3] == 's' && s[i + 4] == 'e') {
         i += 5;
-        new(&v) mixed(false);
+        new (&v) mixed(false);
         return true;
       }
       break;
@@ -364,8 +355,7 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
                   }
 
                   if (0xD7FF < num && num < 0xE000) {
-                    if (s[i + 1] == '\\' && s[i + 2] == 'u' &&
-                        isxdigit(s[i + 3]) && isxdigit(s[i + 4]) && isxdigit(s[i + 5]) && isxdigit(s[i + 6])) {
+                    if (s[i + 1] == '\\' && s[i + 2] == 'u' && isxdigit(s[i + 3]) && isxdigit(s[i + 4]) && isxdigit(s[i + 5]) && isxdigit(s[i + 6])) {
                       i += 2;
                       int u = 0;
                       for (int t = 0; t < 4; t++) {
@@ -419,7 +409,7 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
         }
         value.shrink(l);
 
-        new(&v) mixed(value);
+        new (&v) mixed(value);
         i++;
         return true;
       }
@@ -446,7 +436,7 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
         i++;
       }
 
-      new(&v) mixed(res);
+      new (&v) mixed(res);
       return true;
     }
     case '{': {
@@ -483,7 +473,7 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
         res[string{json_obj_magic_key}] = true;
       }
 
-      new(&v) mixed(res);
+      new (&v) mixed(res);
       return true;
     }
     default: {
@@ -495,7 +485,7 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
         int64_t intval = 0;
         if (php_try_to_int(s + i, j - i, &intval)) {
           i = j;
-          new(&v) mixed(intval);
+          new (&v) mixed(intval);
           return true;
         }
 
@@ -503,7 +493,7 @@ bool do_json_decode(const char *s, int s_len, int &i, mixed &v, const char *json
         double floatval = strtod(s + i, &end_ptr);
         if (end_ptr == s + j) {
           i = j;
-          new(&v) mixed(floatval);
+          new (&v) mixed(floatval);
           return true;
         }
       }
diff --git a/runtime-light/utils/json-functions.h b/runtime-light/utils/json-functions.h
index 15626a7e23..7805da79d9 100644
--- a/runtime-light/utils/json-functions.h
+++ b/runtime-light/utils/json-functions.h
@@ -9,7 +9,6 @@
 #include "common/mixin/not_copyable.h"
 #include "runtime-core/runtime-core.h"
 
-
 constexpr int64_t JSON_UNESCAPED_UNICODE = 1;
 constexpr int64_t JSON_FORCE_OBJECT = 16;
 constexpr int64_t JSON_PRETTY_PRINT = 128; // TODO: add actual support to untyped
@@ -22,7 +21,7 @@ constexpr int64_t JSON_AVAILABLE_FLAGS_TYPED = JSON_PRETTY_PRINT | JSON_PRESERVE
 struct JsonPath {
   constexpr static int MAX_DEPTH = 8;
 
-  std::array<const char*, MAX_DEPTH> arr;
+  std::array<const char *, MAX_DEPTH> arr;
   unsigned depth = 0;
 
   void enter(const char *key) noexcept {
@@ -47,31 +46,31 @@ class JsonEncoder : vk::not_copyable {
 public:
   JsonEncoder(int64_t options, bool simple_encode, const char *json_obj_magic_key = nullptr) noexcept;
 
-  //todo:k2 change static_SB everywhere to string_buffer arg
-  bool encode(bool b, string_buffer & sb) noexcept;
-  bool encode(int64_t i, string_buffer & sb) noexcept;
-  bool encode(const string &s, string_buffer & sb) noexcept;
-  bool encode(double d, string_buffer & sb) noexcept;
-  bool encode(const mixed &v, string_buffer & sb) noexcept;
+  // todo:k2 change static_SB everywhere to string_buffer arg
+  bool encode(bool b, string_buffer &sb) noexcept;
+  bool encode(int64_t i, string_buffer &sb) noexcept;
+  bool encode(const string &s, string_buffer &sb) noexcept;
+  bool encode(double d, string_buffer &sb) noexcept;
+  bool encode(const mixed &v, string_buffer &sb) noexcept;
 
   template<class T>
-  bool encode(const array<T> &arr, string_buffer & sb) noexcept;
+  bool encode(const array<T> &arr, string_buffer &sb) noexcept;
 
   template<class T>
-  bool encode(const Optional<T> &opt, string_buffer & sb) noexcept;
+  bool encode(const Optional<T> &opt, string_buffer &sb) noexcept;
 
 private:
-  bool encode_null(string_buffer & sb) const noexcept;
+  bool encode_null(string_buffer &sb) const noexcept;
 
   JsonPath json_path_;
   const int64_t options_{0};
-  //todo:k2 use simple_encode
+  // todo:k2 use simple_encode
   [[maybe_unused]] const bool simple_encode_{false};
   const char *json_obj_magic_key_{nullptr};
 };
 
 template<class T>
-bool JsonEncoder::encode(const array<T> &arr, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(const array<T> &arr, string_buffer &sb) noexcept {
   bool is_vector = arr.is_vector();
   const bool force_object = static_cast<bool>(JSON_FORCE_OBJECT & options_);
   if (!force_object && !is_vector && arr.is_pseudo_vector()) {
@@ -142,7 +141,7 @@ bool JsonEncoder::encode(const array<T> &arr, string_buffer & sb) noexcept {
 }
 
 template<class T>
-bool JsonEncoder::encode(const Optional<T> &opt, string_buffer & sb) noexcept {
+bool JsonEncoder::encode(const Optional<T> &opt, string_buffer &sb) noexcept {
   switch (opt.value_state()) {
     case OptionalState::has_value:
       return encode(opt.val(), sb);
@@ -170,7 +169,7 @@ Optional<string> f$json_encode(const T &v, int64_t options = 0, bool simple_enco
   return sb.c_str();
 }
 
-//todo:k2 implement string f$vk_json_encode_safe(const T &v, bool simple_encode = true) noexcept
+// todo:k2 implement string f$vk_json_encode_safe(const T &v, bool simple_encode = true) noexcept
 
 template<class T>
 inline Optional<string> f$vk_json_encode(const T &v) noexcept {
diff --git a/runtime-light/utils/php_assert.cpp b/runtime-light/utils/php_assert.cpp
index 190caca8d3..0d869406bd 100644
--- a/runtime-light/utils/php_assert.cpp
+++ b/runtime-light/utils/php_assert.cpp
@@ -2,6 +2,9 @@
 // Copyright (c) 2020 LLC «V Kontakte»
 // Distributed under the GPL v3 License, see LICENSE.notice.txt
 
+#include "runtime-light/utils/php_assert.h"
+
+#include <algorithm>
 #include <csignal>
 #include <cstdarg>
 #include <cstdio>
@@ -13,10 +16,7 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
-#include "runtime-core/utils/kphp-assert-core.h"
-#include "runtime-light/header.h"
-#include "runtime-light/utils/context.h"
-#include "runtime-light/utils/logs.h"
+#include "runtime-light/utils/panic.h"
 
 static void php_warning_impl(bool out_of_memory, int error_type, char const *message, va_list args) {
   (void)out_of_memory;
diff --git a/runtime-light/utils/to-array-processor.h b/runtime-light/utils/to-array-processor.h
index 19ac809395..47ff7ec4a2 100644
--- a/runtime-light/utils/to-array-processor.h
+++ b/runtime-light/utils/to-array-processor.h
@@ -86,7 +86,7 @@ class ToArrayVisitor {
     add_value(field_name, instance.is_null() ? mixed{} : f$to_array_debug(instance, with_class_names_));
   }
 
-  template<class ...Args>
+  template<class... Args>
   void process_impl(const char *field_name, const std::tuple<Args...> &value) {
     ToArrayVisitor tuple_processor{with_class_names_};
     tuple_processor.result_.reserve(sizeof...(Args), true);
@@ -95,7 +95,7 @@ class ToArrayVisitor {
     add_value(field_name, std::move(tuple_processor).flush_result());
   }
 
-  template<size_t ...Is, typename ...T>
+  template<size_t... Is, typename... T>
   void process_impl(const char *field_name, const shape<std::index_sequence<Is...>, T...> &value) {
     ToArrayVisitor shape_processor{with_class_names_};
     shape_processor.result_.reserve(sizeof...(Is), true);
diff --git a/runtime-light/utils/utils.cmake b/runtime-light/utils/utils.cmake
index f74079da0d..b25f9b6b3d 100644
--- a/runtime-light/utils/utils.cmake
+++ b/runtime-light/utils/utils.cmake
@@ -1 +1,5 @@
-prepend(RUNTIME_UTILS_SRC utils/ panic.cpp php_assert.cpp json-functions.cpp context.cpp)
+prepend(RUNTIME_UTILS_SRC utils/
+        php_assert.cpp
+        json-functions.cpp
+        context.cpp
+        timer.cpp)