diff --git a/clang-tools-extra/CMakeLists.txt b/clang-tools-extra/CMakeLists.txt
index 6b6f2b1ca2276..87050db4e0e75 100644
--- a/clang-tools-extra/CMakeLists.txt
+++ b/clang-tools-extra/CMakeLists.txt
@@ -5,6 +5,8 @@ include(GNUInstallDirs)
 
 option(CLANG_TIDY_ENABLE_STATIC_ANALYZER
   "Include static analyzer checks in clang-tidy" ON)
+option(CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
+  "Enable query-based custom checks in clang-tidy" ON)
 
 if(CLANG_INCLUDE_TESTS)
   umbrella_lit_testsuite_begin(check-clang-tools)
diff --git a/clang-tools-extra/clang-tidy/CMakeLists.txt b/clang-tools-extra/clang-tidy/CMakeLists.txt
index 93117cf1d6373..153356245cfd1 100644
--- a/clang-tools-extra/clang-tidy/CMakeLists.txt
+++ b/clang-tools-extra/clang-tidy/CMakeLists.txt
@@ -58,6 +58,7 @@ add_subdirectory(bugprone)
 add_subdirectory(cert)
 add_subdirectory(concurrency)
 add_subdirectory(cppcoreguidelines)
+add_subdirectory(custom)
 add_subdirectory(darwin)
 add_subdirectory(fuchsia)
 add_subdirectory(google)
@@ -101,6 +102,10 @@ set(ALL_CLANG_TIDY_CHECKS
   clangTidyReadabilityModule
   clangTidyZirconModule
   )
+
+if(CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS)
+  list(APPEND ALL_CLANG_TIDY_CHECKS clangTidyCustomModule)
+endif()
 if(CLANG_TIDY_ENABLE_STATIC_ANALYZER)
   list(APPEND ALL_CLANG_TIDY_CHECKS clangTidyMPIModule)
 endif()
diff --git a/clang-tools-extra/clang-tidy/ClangTidy.cpp b/clang-tools-extra/clang-tidy/ClangTidy.cpp
index f4ab93b51f4a7..95726337df91f 100644
--- a/clang-tools-extra/clang-tidy/ClangTidy.cpp
+++ b/clang-tools-extra/clang-tidy/ClangTidy.cpp
@@ -53,6 +53,11 @@ LLVM_INSTANTIATE_REGISTRY(clang::tidy::ClangTidyModuleRegistry)
 
 namespace clang::tidy {
 
+namespace custom {
+extern void registerCustomChecks(const ClangTidyOptions &O,
+                                 ClangTidyCheckFactories &Factories);
+} // namespace custom
+
 namespace {
 #if CLANG_TIDY_ENABLE_STATIC_ANALYZER
 static const char *AnalyzerCheckNamePrefix = "clang-analyzer-";
@@ -341,6 +346,9 @@ ClangTidyASTConsumerFactory::ClangTidyASTConsumerFactory(
     IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem> OverlayFS)
     : Context(Context), OverlayFS(std::move(OverlayFS)),
       CheckFactories(new ClangTidyCheckFactories) {
+#if CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
+  custom::registerCustomChecks(Context.getOptions(), *CheckFactories);
+#endif
   for (ClangTidyModuleRegistry::entry E : ClangTidyModuleRegistry::entries()) {
     std::unique_ptr<ClangTidyModule> Module = E.instantiate();
     Module->addCheckFactories(*CheckFactories);
@@ -411,7 +419,9 @@ ClangTidyASTConsumerFactory::createASTConsumer(
                         .getCurrentWorkingDirectory();
   if (WorkingDir)
     Context.setCurrentBuildDirectory(WorkingDir.get());
-
+#if CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
+  custom::registerCustomChecks(Context.getOptions(), *CheckFactories);
+#endif
   std::vector<std::unique_ptr<ClangTidyCheck>> Checks =
       CheckFactories->createChecksForLanguage(&Context);
 
@@ -651,6 +661,9 @@ getAllChecksAndOptions(bool AllowEnablingAnalyzerAlphaCheckers) {
       std::make_unique<DefaultOptionsProvider>(ClangTidyGlobalOptions(), Opts),
       AllowEnablingAnalyzerAlphaCheckers);
   ClangTidyCheckFactories Factories;
+#if CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
+  custom::registerCustomChecks(Context.getOptions(), Factories);
+#endif
   for (const ClangTidyModuleRegistry::entry &Module :
        ClangTidyModuleRegistry::entries()) {
     Module.instantiate()->addCheckFactories(Factories);
diff --git a/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h b/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h
index adde9136ff1dd..cdf6ce2045a5d 100644
--- a/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h
+++ b/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h
@@ -54,6 +54,13 @@ extern volatile int CppCoreGuidelinesModuleAnchorSource;
 static int LLVM_ATTRIBUTE_UNUSED CppCoreGuidelinesModuleAnchorDestination =
     CppCoreGuidelinesModuleAnchorSource;
 
+#if CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
+// This anchor is used to force the linker to link the CustomModule.
+extern volatile int CustomModuleAnchorSource;
+static int LLVM_ATTRIBUTE_UNUSED CustomModuleAnchorDestination =
+    CustomModuleAnchorSource;
+#endif
+
 // This anchor is used to force the linker to link the DarwinModule.
 extern volatile int DarwinModuleAnchorSource;
 static int LLVM_ATTRIBUTE_UNUSED DarwinModuleAnchorDestination =
diff --git a/clang-tools-extra/clang-tidy/ClangTidyModule.h b/clang-tools-extra/clang-tidy/ClangTidyModule.h
index 28f54331755a7..d818ea926a567 100644
--- a/clang-tools-extra/clang-tidy/ClangTidyModule.h
+++ b/clang-tools-extra/clang-tidy/ClangTidyModule.h
@@ -62,6 +62,8 @@ class ClangTidyCheckFactories {
                          });
   }
 
+  void eraseCheck(llvm::StringRef CheckName) { Factories.erase(CheckName); }
+
   /// Create instances of checks that are enabled.
   std::vector<std::unique_ptr<ClangTidyCheck>>
   createChecks(ClangTidyContext *Context) const;
diff --git a/clang-tools-extra/clang-tidy/ClangTidyOptions.cpp b/clang-tools-extra/clang-tidy/ClangTidyOptions.cpp
index e59f157b468bc..646a3a0a08c8b 100644
--- a/clang-tools-extra/clang-tidy/ClangTidyOptions.cpp
+++ b/clang-tools-extra/clang-tidy/ClangTidyOptions.cpp
@@ -8,8 +8,10 @@
 
 #include "ClangTidyOptions.h"
 #include "ClangTidyModuleRegistry.h"
+#include "clang/Basic/DiagnosticIDs.h"
 #include "clang/Basic/LLVM.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/MemoryBufferRef.h"
@@ -125,6 +127,51 @@ void yamlize(IO &IO, ClangTidyOptions::OptionMap &Val, bool,
   }
 }
 
+namespace {
+struct MultiLineString {
+  std::string &S;
+};
+} // namespace
+
+template <> struct BlockScalarTraits<MultiLineString> {
+  static void output(const MultiLineString &S, void *Ctxt, raw_ostream &OS) {
+    OS << S.S;
+  }
+  static StringRef input(StringRef Str, void *Ctxt, MultiLineString &S) {
+    S.S = Str;
+    return "";
+  }
+};
+
+template <> struct ScalarEnumerationTraits<clang::DiagnosticIDs::Level> {
+  static void enumeration(IO &IO, clang::DiagnosticIDs::Level &Level) {
+    IO.enumCase(Level, "Warning", clang::DiagnosticIDs::Level::Warning);
+    IO.enumCase(Level, "Note", clang::DiagnosticIDs::Level::Note);
+  }
+};
+template <> struct SequenceElementTraits<ClangTidyOptions::CustomCheckDiag> {
+  static const bool flow = false;
+};
+template <> struct MappingTraits<ClangTidyOptions::CustomCheckDiag> {
+  static void mapping(IO &IO, ClangTidyOptions::CustomCheckDiag &D) {
+    IO.mapRequired("BindName", D.BindName);
+    MultiLineString MLS{D.Message};
+    IO.mapRequired("Message", MLS);
+    IO.mapOptional("Level", D.Level);
+  }
+};
+template <> struct SequenceElementTraits<ClangTidyOptions::CustomCheckValue> {
+  static const bool flow = false;
+};
+template <> struct MappingTraits<ClangTidyOptions::CustomCheckValue> {
+  static void mapping(IO &IO, ClangTidyOptions::CustomCheckValue &V) {
+    IO.mapRequired("Name", V.Name);
+    MultiLineString MLS{V.Query};
+    IO.mapRequired("Query", MLS);
+    IO.mapRequired("Diagnostic", V.Diags);
+  }
+};
+
 struct ChecksVariant {
   std::optional<std::string> AsString;
   std::optional<std::vector<std::string>> AsVector;
@@ -180,6 +227,7 @@ template <> struct MappingTraits<ClangTidyOptions> {
     IO.mapOptional("InheritParentConfig", Options.InheritParentConfig);
     IO.mapOptional("UseColor", Options.UseColor);
     IO.mapOptional("SystemHeaders", Options.SystemHeaders);
+    IO.mapOptional("CustomChecks", Options.CustomChecks);
   }
 };
 
@@ -241,7 +289,8 @@ ClangTidyOptions &ClangTidyOptions::mergeWith(const ClangTidyOptions &Other,
   overrideValue(UseColor, Other.UseColor);
   mergeVectors(ExtraArgs, Other.ExtraArgs);
   mergeVectors(ExtraArgsBefore, Other.ExtraArgsBefore);
-
+  // FIXME: how to handle duplicate names check?
+  mergeVectors(CustomChecks, Other.CustomChecks);
   for (const auto &KeyValue : Other.CheckOptions) {
     CheckOptions.insert_or_assign(
         KeyValue.getKey(),
diff --git a/clang-tools-extra/clang-tidy/ClangTidyOptions.h b/clang-tools-extra/clang-tidy/ClangTidyOptions.h
index 6ddc5f9b9cf9e..0f52925a7c765 100644
--- a/clang-tools-extra/clang-tidy/ClangTidyOptions.h
+++ b/clang-tools-extra/clang-tidy/ClangTidyOptions.h
@@ -9,6 +9,7 @@
 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYOPTIONS_H
 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYOPTIONS_H
 
+#include "clang/Basic/DiagnosticIDs.h"
 #include "llvm/ADT/IntrusiveRefCntPtr.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringMap.h"
@@ -129,6 +130,19 @@ struct ClangTidyOptions {
   /// Key-value mapping used to store check-specific options.
   OptionMap CheckOptions;
 
+  struct CustomCheckDiag {
+    std::string BindName;
+    std::string Message;
+    std::optional<DiagnosticIDs::Level> Level;
+  };
+  struct CustomCheckValue {
+    std::string Name;
+    std::string Query;
+    llvm::SmallVector<CustomCheckDiag> Diags;
+  };
+  using CustomCheckValueList = llvm::SmallVector<CustomCheckValue>;
+  std::optional<CustomCheckValueList> CustomChecks;
+
   using ArgList = std::vector<std::string>;
 
   /// Add extra compilation arguments to the end of the list.
diff --git a/clang-tools-extra/clang-tidy/clang-tidy-config.h.cmake b/clang-tools-extra/clang-tidy/clang-tidy-config.h.cmake
index f4d1a4b38004b..400e89ea60b33 100644
--- a/clang-tools-extra/clang-tidy/clang-tidy-config.h.cmake
+++ b/clang-tools-extra/clang-tidy/clang-tidy-config.h.cmake
@@ -6,5 +6,6 @@
 #define CLANG_TIDY_CONFIG_H
 
 #cmakedefine01 CLANG_TIDY_ENABLE_STATIC_ANALYZER
+#cmakedefine01 CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
 
 #endif
diff --git a/clang-tools-extra/clang-tidy/custom/CMakeLists.txt b/clang-tools-extra/clang-tidy/custom/CMakeLists.txt
new file mode 100644
index 0000000000000..0b43387970903
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/custom/CMakeLists.txt
@@ -0,0 +1,22 @@
+if(CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS)
+  set(LLVM_LINK_COMPONENTS
+    support
+  )
+
+  add_clang_library(clangTidyCustomModule STATIC
+    CustomTidyModule.cpp
+    QueryCheck.cpp
+
+    LINK_LIBS
+    clangTidy
+    clangTidyUtils
+
+    DEPENDS
+    ClangDriverOptions
+  )
+
+  clang_target_link_libraries(clangTidyCustomModule
+    PRIVATE
+    clangQuery
+  )
+endif()
diff --git a/clang-tools-extra/clang-tidy/custom/CustomTidyModule.cpp b/clang-tools-extra/clang-tidy/custom/CustomTidyModule.cpp
new file mode 100644
index 0000000000000..4ec9501dd4c2c
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/custom/CustomTidyModule.cpp
@@ -0,0 +1,50 @@
+#include "../ClangTidy.h"
+#include "../ClangTidyModule.h"
+#include "../ClangTidyModuleRegistry.h"
+#include "../ClangTidyOptions.h"
+#include "QueryCheck.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringRef.h"
+#include <memory>
+
+namespace clang::tidy {
+namespace custom {
+
+class CustomModule : public ClangTidyModule {
+public:
+  void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {}
+};
+
+// We need to register the checks more flexibly than builtin modules. The checks
+// will changed dynamically when switching to different source file.
+extern void registerCustomChecks(const ClangTidyOptions &Options,
+                                 ClangTidyCheckFactories &Factories) {
+  static llvm::SmallSet<llvm::SmallString<32>, 8> CustomCheckNames{};
+  if (!Options.CustomChecks.has_value() || Options.CustomChecks->empty())
+    return;
+  for (const llvm::SmallString<32> &Name : CustomCheckNames)
+    Factories.eraseCheck(Name);
+  for (const ClangTidyOptions::CustomCheckValue &V :
+       Options.CustomChecks.value()) {
+    llvm::SmallString<32> Name = llvm::StringRef{"custom-" + V.Name};
+    Factories.registerCheckFactory(
+        // add custom- prefix to avoid conflicts with builtin checks
+        Name, [&V](llvm::StringRef Name, ClangTidyContext *Context) {
+          return std::make_unique<custom::QueryCheck>(Name, V, Context);
+        });
+    CustomCheckNames.insert(std::move(Name));
+  }
+}
+
+} // namespace custom
+
+// Register the CustomTidyModule using this statically initialized variable.
+static ClangTidyModuleRegistry::Add<custom::CustomModule>
+    X("custom-module", "Adds custom query lint checks.");
+
+// This anchor is used to force the linker to link in the generated object file
+// and thus register the AlteraModule.
+volatile int CustomModuleAnchorSource = 0; // NOLINT (misc-use-internal-linkage)
+
+} // namespace clang::tidy
diff --git a/clang-tools-extra/clang-tidy/custom/QueryCheck.cpp b/clang-tools-extra/clang-tidy/custom/QueryCheck.cpp
new file mode 100644
index 0000000000000..f83c138fbfaf5
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/custom/QueryCheck.cpp
@@ -0,0 +1,146 @@
+//===--- QueryCheck.cpp - clang-tidy --------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "QueryCheck.h"
+#include "../../clang-query/Query.h"
+#include "../../clang-query/QueryParser.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/ASTMatchers/Dynamic/VariantValue.h"
+#include "clang/Basic/DiagnosticIDs.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include <string>
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::custom {
+
+static void emitConfigurationDiag(ClangTidyContext *Context, StringRef Message,
+                                  StringRef CheckName) {
+  Context->configurationDiag("%0 in '%1'", DiagnosticIDs::Warning)
+      << Message << CheckName;
+}
+
+static SmallVector<ast_matchers::dynamic::DynTypedMatcher>
+parseQuery(const ClangTidyOptions::CustomCheckValue &V,
+           ClangTidyContext *Context) {
+  SmallVector<ast_matchers::dynamic::DynTypedMatcher> Matchers{};
+  clang::query::QuerySession QS({});
+  llvm::StringRef QueryStringRef{V.Query};
+  while (!QueryStringRef.empty()) {
+    query::QueryRef Q = query::QueryParser::parse(QueryStringRef, QS);
+    switch (Q->Kind) {
+    case query::QK_Match: {
+      const auto &MatchQuery = llvm::cast<query::MatchQuery>(*Q);
+      Matchers.push_back(MatchQuery.Matcher);
+      break;
+    }
+    case query::QK_Let: {
+      const auto &LetQuery = llvm::cast<query::LetQuery>(*Q);
+      LetQuery.run(llvm::errs(), QS);
+      break;
+    }
+    case query::QK_NoOp: {
+      const auto &NoOpQuery = llvm::cast<query::NoOpQuery>(*Q);
+      NoOpQuery.run(llvm::errs(), QS);
+      break;
+    }
+    case query::QK_Invalid: {
+      const auto &InvalidQuery = llvm::cast<query::InvalidQuery>(*Q);
+      emitConfigurationDiag(Context, InvalidQuery.ErrStr, V.Name);
+      return {};
+    }
+    // FIXME: TODO
+    case query::QK_File: {
+      emitConfigurationDiag(Context, "unsupported query kind 'File'", V.Name);
+      return {};
+    }
+    case query::QK_DisableOutputKind: {
+      emitConfigurationDiag(
+          Context, "unsupported query kind 'DisableOutputKind'", V.Name);
+      return {};
+    }
+    case query::QK_EnableOutputKind: {
+      emitConfigurationDiag(
+          Context, "unsupported query kind 'EnableOutputKind'", V.Name);
+      return {};
+    }
+    case query::QK_SetOutputKind: {
+      emitConfigurationDiag(Context, "unsupported query kind 'SetOutputKind'",
+                            V.Name);
+      return {};
+    }
+    case query::QK_SetTraversalKind: {
+      emitConfigurationDiag(
+          Context, "unsupported query kind 'SetTraversalKind'", V.Name);
+      return {};
+    }
+    case query::QK_SetBool: {
+      emitConfigurationDiag(Context, "unsupported query kind 'SetBool'",
+                            V.Name);
+      return {};
+    }
+    case query::QK_Help: {
+      emitConfigurationDiag(Context, "unsupported query kind 'Help'", V.Name);
+      return {};
+    }
+    case query::QK_Quit: {
+      emitConfigurationDiag(Context, "unsupported query kind 'Quit'", V.Name);
+      return {};
+    }
+    }
+    QueryStringRef = Q->RemainingContent;
+  }
+  return Matchers;
+}
+
+QueryCheck::QueryCheck(llvm::StringRef Name,
+                       const ClangTidyOptions::CustomCheckValue &V,
+                       ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context) {
+  for (const ClangTidyOptions::CustomCheckDiag &D : V.Diags) {
+    auto DiagnosticIdIt =
+        Diags
+            .try_emplace(D.Level.value_or(DiagnosticIDs::Warning),
+                         llvm::StringMap<llvm::SmallVector<std::string>>{})
+            .first;
+    auto DiagMessageIt =
+        DiagnosticIdIt->getSecond()
+            .try_emplace(D.BindName, llvm::SmallVector<std::string>{})
+            .first;
+    DiagMessageIt->second.emplace_back(D.Message);
+  }
+  Matchers = parseQuery(V, Context);
+}
+
+void QueryCheck::registerMatchers(MatchFinder *Finder) {
+  for (const ast_matchers::dynamic::DynTypedMatcher &M : Matchers)
+    Finder->addDynamicMatcher(M, this);
+}
+
+void QueryCheck::check(const MatchFinder::MatchResult &Result) {
+  auto Emit = [this](const DiagMaps &DiagMaps, const std::string &BindName,
+                     const DynTypedNode &Node, DiagnosticIDs::Level Level) {
+    DiagMaps::const_iterator DiagMapIt = DiagMaps.find(Level);
+    if (DiagMapIt == DiagMaps.end())
+      return;
+    const BindNameMapToDiagMessage &BindNameMap = DiagMapIt->second;
+    BindNameMapToDiagMessage::const_iterator BindNameMapIt =
+        BindNameMap.find(BindName);
+    if (BindNameMapIt == BindNameMap.end())
+      return;
+    for (const std::string &Message : BindNameMapIt->second)
+      diag(Node.getSourceRange().getBegin(), Message, Level);
+  };
+  for (const auto &[Name, Node] : Result.Nodes.getMap())
+    Emit(Diags, Name, Node, DiagnosticIDs::Warning);
+  // place Note last, otherwise it will not be emitted
+  for (const auto &[Name, Node] : Result.Nodes.getMap())
+    Emit(Diags, Name, Node, DiagnosticIDs::Note);
+}
+} // namespace clang::tidy::custom
diff --git a/clang-tools-extra/clang-tidy/custom/QueryCheck.h b/clang-tools-extra/clang-tidy/custom/QueryCheck.h
new file mode 100644
index 0000000000000..3dcdc518736c2
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/custom/QueryCheck.h
@@ -0,0 +1,41 @@
+//===--- QueryCheck.h - clang-tidy ------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CUSTOM_QUERYCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CUSTOM_QUERYCHECK_H
+
+#include "../ClangTidyCheck.h"
+#include "clang/ASTMatchers/Dynamic/VariantValue.h"
+#include "clang/Basic/DiagnosticIDs.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringMap.h"
+
+namespace clang::tidy::custom {
+
+/// Implement of Clang-Query based check.
+/// Not directly visible to users.
+class QueryCheck : public ClangTidyCheck {
+public:
+  QueryCheck(llvm::StringRef Name, const ClangTidyOptions::CustomCheckValue &V,
+             ClangTidyContext *Context);
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+
+private:
+  llvm::SmallVector<ast_matchers::dynamic::DynTypedMatcher> Matchers;
+  using BindNameMapToDiagMessage =
+      llvm::StringMap<llvm::SmallVector<std::string>>;
+  using DiagMaps =
+      llvm::DenseMap<DiagnosticIDs::Level, BindNameMapToDiagMessage>;
+  DiagMaps Diags;
+};
+
+} // namespace clang::tidy::custom
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CUSTOM_QUERYCHECK_H
diff --git a/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp b/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp
index 4336c723bd7cd..d42c84585d357 100644
--- a/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp
+++ b/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp
@@ -60,6 +60,8 @@ Configuration files:
   Checks                       - Same as '--checks'. Additionally, the list of
                                  globs can be specified as a list instead of a
                                  string.
+  CustomChecks                 - Array of user defined checks based on
+                                 Clang-Query syntax.
   ExcludeHeaderFilterRegex     - Same as '--exclude-header-filter'.
   ExtraArgs                    - Same as '--extra-arg'.
   ExtraArgsBefore              - Same as '--extra-arg-before'.
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index f8f183e9de1cc..27934405a59dc 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -105,6 +105,10 @@ Improvements to clang-tidy
   specific tests. This may break tests for users with custom out-of-tree checks
   who use :program:`check_clang_tidy.py` as-is.
 
+- :program:`clang-tidy` now supports query based custom checks by `CustomChecks`
+  configuration option.
+  :doc:`Query Based Custom Check Document <clang-tidy/QueryBasedCustomChecks>`
+  
 - Improved :program:`clang-tidy-diff.py` script. Add the `-warnings-as-errors`
   argument to treat warnings as errors.
 
diff --git a/clang-tools-extra/docs/clang-tidy/Contributing.rst b/clang-tools-extra/docs/clang-tidy/Contributing.rst
index 9611c655886f2..49621ea1bed04 100644
--- a/clang-tools-extra/docs/clang-tidy/Contributing.rst
+++ b/clang-tools-extra/docs/clang-tidy/Contributing.rst
@@ -33,6 +33,9 @@ If CMake is configured with ``CLANG_TIDY_ENABLE_STATIC_ANALYZER=NO``,
 :program:`clang-tidy` will not be built with support for the
 ``clang-analyzer-*`` checks or the ``mpi-*`` checks.
 
+If CMake is configured with ``CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS=NO``,
+:program:`clang-tidy` will not be built with support for query based checks. 
+
 
 .. _AST Matchers: https://clang.llvm.org/docs/LibASTMatchers.html
 .. _PPCallbacks: https://clang.llvm.org/doxygen/classclang_1_1PPCallbacks.html
diff --git a/clang-tools-extra/docs/clang-tidy/QueryBasedCustomChecks.rst b/clang-tools-extra/docs/clang-tidy/QueryBasedCustomChecks.rst
new file mode 100644
index 0000000000000..0f8bcf1ec84be
--- /dev/null
+++ b/clang-tools-extra/docs/clang-tidy/QueryBasedCustomChecks.rst
@@ -0,0 +1,63 @@
+====================================
+Query Based Custom Clang-Tidy Checks
+====================================
+
+Introduction
+============
+
+This page provides examples of how to add query based custom checks for
+:program:`clang-tidy`.
+
+Custom checks are based on :program:`clang-query` syntax. Every custom checks
+will be registered in `custom` module to avoid name conflict. They can be
+enabled or disabled by the checks option like the built-in checks.
+
+Custom checks support inheritance from parent configurations like other
+configuration items.
+
+Goals: easy to write, cross platform, multiple versions supported toolkit for
+custom clang-tidy rules.
+Non-Goals: complex checks, performance, fix-its, etc.
+
+Configuration
+=============
+
+`CustomChecks` is a list of custom checks. Each check must contain
+  - Name: check name can be used in `-checks` option.
+  - Query: `clang-query` string
+  - Diagnostic: list of diagnostics to be reported.
+    - BindName: name of the node to be bound in `Query`.
+    - Message: message to be reported.
+    - Level: severity of the diagnostic, the possible values are `Note`, `Warning`.
+
+`CustomChecks` can be configured by `Checks` option in the configuration file.
+
+Example
+=======
+
+.. code-block:: yaml
+
+  Checks: -*,custom-call-main-function
+  CustomChecks:
+    - Name: call-main-function
+      Query: |
+          match callExpr(
+            callee(
+              functionDecl(isMain()).bind("fn")
+            )
+          ).bind("callee")
+      Diagnostic:
+        - BindName: fn
+          Message: main function.
+          Level: Note
+        - BindName: callee
+          Message: call to main function.
+          Level: Warning
+
+.. code-block:: c++
+
+  int main(); // note: main function.
+
+  void bar() {
+    main(); // warning: call to main function. [custom-call-main-function]
+  }
diff --git a/clang-tools-extra/docs/clang-tidy/index.rst b/clang-tools-extra/docs/clang-tidy/index.rst
index b7a366e874130..b218e0034825c 100644
--- a/clang-tools-extra/docs/clang-tidy/index.rst
+++ b/clang-tools-extra/docs/clang-tidy/index.rst
@@ -10,6 +10,7 @@ See also:
    :maxdepth: 1
 
    List of Clang-Tidy Checks <checks/list>
+   Query Based Custom Clang-Tidy Checks <QueryBasedCustomChecks>
    Clang-tidy IDE/Editor Integrations <Integrations>
    Getting Involved <Contributing>
    External Clang-Tidy Examples <ExternalClang-TidyExamples>
@@ -292,6 +293,8 @@ An overview of all the command-line options:
     Checks                       - Same as '--checks'. Additionally, the list of
                                    globs can be specified as a list instead of a
                                    string.
+    CustomChecks                 - List of user defined checks based on
+                                   Clang-Query syntax.
     ExcludeHeaderFilterRegex     - Same as '--exclude-header-filter'.
     ExtraArgs                    - Same as '--extra-arg'.
     ExtraArgsBefore              - Same as '--extra-arg-before'.
diff --git a/clang-tools-extra/test/clang-tidy/checkers/custom/Inputs/clang-tidy.yml b/clang-tools-extra/test/clang-tidy/checkers/custom/Inputs/clang-tidy.yml
new file mode 100644
index 0000000000000..b4524e247feae
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/custom/Inputs/clang-tidy.yml
@@ -0,0 +1,22 @@
+CustomChecks:
+  - Name: test-diag-level
+    Query: |
+      match varDecl(
+          hasType(asString("long")),
+          hasTypeLoc(typeLoc().bind("long"))
+      ).bind("decl")
+    Diagnostic:
+      - BindName: long
+        Message: use 'int' instead of 'long'
+        Level: Warning
+      - BindName: decl
+        Message: declaration of 'long'
+        Level: Note
+  - Name: test-let-bind
+    Query: |
+      let expr varDecl(isStaticStorageClass()).bind("vd")
+      match expr
+    Diagnostic:
+      - BindName: vd
+        Message: find static variable
+        Level: Warning
diff --git a/clang-tools-extra/test/clang-tidy/checkers/custom/Inputs/incorrect-clang-tidy.yml b/clang-tools-extra/test/clang-tidy/checkers/custom/Inputs/incorrect-clang-tidy.yml
new file mode 100644
index 0000000000000..b94ba32997029
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/custom/Inputs/incorrect-clang-tidy.yml
@@ -0,0 +1,25 @@
+CustomChecks:
+  - Name: test-let-bind-invalid-1
+    Query: |
+      let expr varDecl(isStaticStorageClass()).bind("vd")
+      match expr
+      set output print
+    Diagnostic:
+      - BindName: vd
+        Message: find static variable
+        Level: Warning
+  - Name: test-let-bind-invalid-2
+    Query: |
+      match varDeclInvalid(isStaticStorageClass()).bind("vd")
+    Diagnostic:
+      - BindName: vd
+        Message: find static variable
+        Level: Warning
+  - Name: test-let-bind-valid
+    Query: |
+      let expr varDecl(isStaticStorageClass()).bind("vd")
+      match expr
+    Diagnostic:
+      - BindName: vd
+        Message: find static variable
+        Level: Warning
diff --git a/clang-tools-extra/test/clang-tidy/checkers/custom/query-incorrect-query.cpp b/clang-tools-extra/test/clang-tidy/checkers/custom/query-incorrect-query.cpp
new file mode 100644
index 0000000000000..f9a73750b4c3e
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/custom/query-incorrect-query.cpp
@@ -0,0 +1,7 @@
+// RUN: %check_clang_tidy %s custom-* %t --config-file=%S/Inputs/incorrect-clang-tidy.yml
+
+// CHECK-MESSAGES: warning: 1:1: Matcher not found: varDeclInvalid in 'test-let-bind-invalid-2' [clang-tidy-config]
+// CHECK-MESSAGES: warning: unsupported query kind 'SetOutputKind' in 'test-let-bind-invalid-1' [clang-tidy-config]
+
+static int S;
+// CHECK-MESSAGES: [[@LINE-1]]:1: warning: find static variable [custom-test-let-bind-valid]
diff --git a/clang-tools-extra/test/clang-tidy/checkers/custom/query-partially-active-check.cpp b/clang-tools-extra/test/clang-tidy/checkers/custom/query-partially-active-check.cpp
new file mode 100644
index 0000000000000..962313ddb587b
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/custom/query-partially-active-check.cpp
@@ -0,0 +1,5 @@
+// RUN: %check_clang_tidy %s custom-test-let-bind %t --config-file=%S/Inputs/clang-tidy.yml
+
+extern long E;
+static int S;
+// CHECK-MESSAGES: [[@LINE-1]]:1: warning: find static variable [custom-test-let-bind]
diff --git a/clang-tools-extra/test/clang-tidy/checkers/custom/query.cpp b/clang-tools-extra/test/clang-tidy/checkers/custom/query.cpp
new file mode 100644
index 0000000000000..e9a27301bd611
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/custom/query.cpp
@@ -0,0 +1,7 @@
+// RUN: %check_clang_tidy %s custom-* %t --config-file=%S/Inputs/clang-tidy.yml
+
+extern long E;
+// CHECK-MESSAGES: [[@LINE-1]]:8: warning: use 'int' instead of 'long' [custom-test-diag-level]
+// CHECK-MESSAGES: [[@LINE-2]]:1: note: declaration of 'long'
+static int S;
+// CHECK-MESSAGES: [[@LINE-1]]:1: warning: find static variable [custom-test-let-bind]
diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/append-clang-tidy.yml b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/append-clang-tidy.yml
new file mode 100644
index 0000000000000..5b25ec061ba63
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/append-clang-tidy.yml
@@ -0,0 +1,8 @@
+InheritParentConfig: true
+CustomChecks:
+  - Name: function-decl
+    Query: match functionDecl().bind("func")
+    Diagnostic:
+      - BindName: func
+        Message: find function decl
+        Level: Warning
diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/empty-clang-tidy.yml b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/empty-clang-tidy.yml
new file mode 100644
index 0000000000000..2e9a13e720f4e
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/empty-clang-tidy.yml
@@ -0,0 +1 @@
+InheritParentConfig: false
diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/override-clang-tidy.yml b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/override-clang-tidy.yml
new file mode 100644
index 0000000000000..ec243b8396ea8
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/override-clang-tidy.yml
@@ -0,0 +1,11 @@
+CustomChecks:
+  - Name: avoid-long-type
+    Query: |
+      match varDecl(
+          hasType(asString("long")),
+          hasTypeLoc(typeLoc().bind("long"))
+      )
+    Diagnostic:
+      - BindName: long
+        Message: use 'int' instead of 'long' override
+        Level: Warning
diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/root-clang-tidy.yml b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/root-clang-tidy.yml
new file mode 100644
index 0000000000000..861ed10be1a5f
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/root-clang-tidy.yml
@@ -0,0 +1,11 @@
+CustomChecks:
+  - Name: avoid-long-type
+    Query: |
+      match varDecl(
+          hasType(asString("long")),
+          hasTypeLoc(typeLoc().bind("long"))
+      )
+    Diagnostic:
+      - BindName: long
+        Message: use 'int' instead of 'long'
+        Level: Warning
diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/vfsoverlay.yaml b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/vfsoverlay.yaml
new file mode 100644
index 0000000000000..2b507f60092c3
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/infrastructure/Inputs/custom-query-check/vfsoverlay.yaml
@@ -0,0 +1,44 @@
+version: 0
+roots:
+  - name: OUT_DIR
+    type: directory
+    contents:
+      - name: .clang-tidy
+        type: file
+        external-contents: INPUT_DIR/root-clang-tidy.yml
+      - name: main.cpp
+        type: file
+        external-contents: MAIN_FILE
+      - name: subdir
+        type: directory
+        contents:
+          - name: main.cpp
+            type: file
+            external-contents: MAIN_FILE
+      - name: subdir-override
+        type: directory
+        contents:
+          - name: main.cpp
+            type: file
+            external-contents: MAIN_FILE
+          - name: .clang-tidy
+            type: file
+            external-contents: INPUT_DIR/override-clang-tidy.yml
+      - name: subdir-empty
+        type: directory
+        contents:
+          - name: main.cpp
+            type: file
+            external-contents: MAIN_FILE
+          - name: .clang-tidy
+            type: file
+            external-contents: INPUT_DIR/empty-clang-tidy.yml
+      - name: subdir-append
+        type: directory
+        contents:
+          - name: main.cpp
+            type: file
+            external-contents: MAIN_FILE
+          - name: .clang-tidy
+            type: file
+            external-contents: INPUT_DIR/append-clang-tidy.yml
diff --git a/clang-tools-extra/test/clang-tidy/infrastructure/custom-query-check.cpp b/clang-tools-extra/test/clang-tidy/infrastructure/custom-query-check.cpp
new file mode 100644
index 0000000000000..13834660385d1
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/infrastructure/custom-query-check.cpp
@@ -0,0 +1,45 @@
+// RUN: sed -e "s:INPUT_DIR:%S/Inputs/custom-query-check:g" -e "s:OUT_DIR:%t:g" -e "s:MAIN_FILE:%s:g" %S/Inputs/custom-query-check/vfsoverlay.yaml > %t.yaml
+// RUN: clang-tidy %t/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml | FileCheck %s --check-prefix=CHECK-SAME-DIR
+// RUN: clang-tidy %t/subdir/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml | FileCheck %s --check-prefix=CHECK-SUB-DIR-BASE
+// RUN: clang-tidy %t/subdir-override/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml | FileCheck %s --check-prefix=CHECK-SUB-DIR-OVERRIDE
+// RUN: clang-tidy %t/subdir-empty/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml --allow-no-checks | FileCheck %s --check-prefix=CHECK-SUB-DIR-EMPTY
+// RUN: clang-tidy %t/subdir-append/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml | FileCheck %s --check-prefix=CHECK-SUB-DIR-APPEND
+// RUN: clang-tidy %t/subdir-append/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml --list-checks | FileCheck %s --check-prefix=LIST-CHECK
+// RUN: clang-tidy %t/subdir-append/main.cpp -checks='-*,custom-*' -vfsoverlay %t.yaml --dump-config | FileCheck %s --check-prefix=DUMP-CONFIG
+// REQUIRES: shell
+
+
+long V;
+// CHECK-SAME-DIR: [[@LINE-1]]:1: warning: use 'int' instead of 'long' [custom-avoid-long-type]
+// CHECK-SUB-DIR-BASE: [[@LINE-2]]:1: warning: use 'int' instead of 'long' [custom-avoid-long-type]
+// CHECK-SUB-DIR-OVERRIDE: [[@LINE-3]]:1: warning: use 'int' instead of 'long' override [custom-avoid-long-type]
+// CHECK-SUB-DIR-EMPTY: No checks enabled.
+// CHECK-SUB-DIR-APPEND: [[@LINE-5]]:1: warning: use 'int' instead of 'long' [custom-avoid-long-type]
+
+void f();
+// CHECK-SUB-DIR-APPEND: [[@LINE-1]]:1: warning: find function decl [custom-function-decl]
+
+// LIST-CHECK: Enabled checks:
+// LIST-CHECK:   custom-avoid-long-type
+// LIST-CHECK:   custom-function-decl
+
+// DUMP-CONFIG: CustomChecks:
+// DUMP-CONFIG: - Name: avoid-long-type
+// DUMP-CONFIG:   Query: |
+// DUMP-CONFIG:     match varDecl(
+// DUMP-CONFIG:       hasType(asString("long")),
+// DUMP-CONFIG:       hasTypeLoc(typeLoc().bind("long"))
+// DUMP-CONFIG:     )
+// DUMP-CONFIG:   Diagnostic:
+// DUMP-CONFIG:    - BindName: long
+// DUMP-CONFIG:      Message: |
+// DUMP-CONFIG:           use 'int' instead of 'long'
+// DUMP-CONFIG:      Level:           Warning
+// DUMP-CONFIG: - Name: function-decl
+// DUMP-CONFIG:   Query: |
+// DUMP-CONFIG:     match functionDecl().bind("func")
+// DUMP-CONFIG:   Diagnostic:
+// DUMP-CONFIG:    - BindName: func
+// DUMP-CONFIG:      Message: |
+// DUMP-CONFIG:        find function decl
+// DUMP-CONFIG:   Level: Warning
diff --git a/clang-tools-extra/unittests/clang-tidy/CMakeLists.txt b/clang-tools-extra/unittests/clang-tidy/CMakeLists.txt
index 3304924d39757..a3f20f5c1359f 100644
--- a/clang-tools-extra/unittests/clang-tidy/CMakeLists.txt
+++ b/clang-tools-extra/unittests/clang-tidy/CMakeLists.txt
@@ -54,6 +54,7 @@ target_link_libraries(ClangTidyTests
   PRIVATE
   clangTidy
   clangTidyAndroidModule
+  clangTidyCustomModule
   clangTidyGoogleModule
   clangTidyMiscModule
   clangTidyLLVMModule