diff --git a/extensions/fine_python_pyrefly/README.md b/extensions/fine_python_pyrefly/README.md
new file mode 100644
index 0000000..492a5f3
--- /dev/null
+++ b/extensions/fine_python_pyrefly/README.md
@@ -0,0 +1,3 @@
+# fine_python_pyrefly
+
+FineCode extension for Pyrefly type checker integration.
diff --git a/extensions/fine_python_pyrefly/fine_python_pyrefly/__init__.py b/extensions/fine_python_pyrefly/fine_python_pyrefly/__init__.py
new file mode 100644
index 0000000..d9e6a9c
--- /dev/null
+++ b/extensions/fine_python_pyrefly/fine_python_pyrefly/__init__.py
@@ -0,0 +1,6 @@
+from .lint_handler import PyreflyLintHandler, PyreflyLintHandlerConfig
+
+__all__ = [
+    "PyreflyLintHandler",
+    "PyreflyLintHandlerConfig",
+]
\ No newline at end of file
diff --git a/extensions/fine_python_pyrefly/fine_python_pyrefly/lint_handler.py b/extensions/fine_python_pyrefly/fine_python_pyrefly/lint_handler.py
new file mode 100644
index 0000000..3e15608
--- /dev/null
+++ b/extensions/fine_python_pyrefly/fine_python_pyrefly/lint_handler.py
@@ -0,0 +1,134 @@
+from __future__ import annotations
+
+import dataclasses
+import json
+import sys
+from pathlib import Path
+
+from finecode_extension_api import code_action
+from finecode_extension_api.actions import lint as lint_action
+from finecode_extension_api.interfaces import icache, icommandrunner, ilogger, ifilemanager
+
+
+@dataclasses.dataclass
+class PyreflyLintHandlerConfig(code_action.ActionHandlerConfig):
+    ...
+
+
+class PyreflyLintHandler(
+    code_action.ActionHandler[lint_action.LintAction, PyreflyLintHandlerConfig]
+):
+    """
+    NOTE: pyrefly currently can check only saved files, not file content provided by
+    FineCode. In environments like IDE, messages from pyrefly will be updated only after
+    save of a file.
+    """
+    CACHE_KEY = "PyreflyLinter"
+
+    def __init__(
+        self,
+        config: PyreflyLintHandlerConfig,
+        cache: icache.ICache,
+        logger: ilogger.ILogger,
+        file_manager: ifilemanager.IFileManager,
+        command_runner: icommandrunner.ICommandRunner,
+    ) -> None:
+        self.config = config
+        self.cache = cache
+        self.logger = logger
+        self.file_manager = file_manager
+        self.command_runner = command_runner
+        
+        self.pyrefly_bin_path = Path(sys.executable).parent / "pyrefly"
+
+    async def run_on_single_file(
+        self, file_path: Path
+    ) -> lint_action.LintRunResult:
+        messages = {}
+        try:
+            cached_lint_messages = await self.cache.get_file_cache(
+                file_path, self.CACHE_KEY
+            )
+            messages[str(file_path)] = cached_lint_messages
+            return lint_action.LintRunResult(messages=messages)
+        except icache.CacheMissException:
+            pass
+
+        file_version = await self.file_manager.get_file_version(file_path)
+        lint_messages = await self.run_pyrefly_lint_on_single_file(file_path)
+        messages[str(file_path)] = lint_messages
+        await self.cache.save_file_cache(
+            file_path, file_version, self.CACHE_KEY, lint_messages
+        )
+
+        return lint_action.LintRunResult(messages=messages)
+
+    async def run(
+        self,
+        payload: lint_action.LintRunPayload,
+        run_context: code_action.RunActionWithPartialResultsContext,
+    ) -> None:
+        file_paths = [file_path async for file_path in payload]
+
+        for file_path in file_paths:
+            run_context.partial_result_scheduler.schedule(
+                file_path,
+                self.run_on_single_file(file_path),
+            )
+
+    async def run_pyrefly_lint_on_single_file(
+        self,
+        file_path: Path,
+    ) -> list[lint_action.LintMessage]:
+        """Run pyrefly type checking on a single file"""
+        lint_messages: list[lint_action.LintMessage] = []
+
+        cmd = [
+            str(self.pyrefly_bin_path),
+            "check",
+            "--output-format",
+            "json",
+            str(file_path),
+        ]
+
+        cmd_str = " ".join(cmd)
+        pyrefly_process = await self.command_runner.run(cmd_str)
+
+        await pyrefly_process.wait_for_end()
+        
+        output = pyrefly_process.get_output()
+        try:
+            pyrefly_results = json.loads(output)
+            for error in pyrefly_results['errors']:
+                lint_message = map_pyrefly_error_to_lint_message(error)
+                lint_messages.append(lint_message)
+        except json.JSONDecodeError:
+            raise code_action.ActionFailedException(f'Output of pyrefly is not json: {output}')
+
+        return lint_messages
+
+
+def map_pyrefly_error_to_lint_message(error: dict) -> lint_action.LintMessage:
+    """Map a pyrefly error to a lint message"""
+    # Extract line/column info (pyrefly uses 1-based indexing)
+    start_line = error['line']
+    start_column = error['column']
+    end_line = error['stop_line']
+    end_column = error['stop_column']
+
+    # Determine severity based on error type
+    error_code = error.get('code', '')
+    code_description = error.get("name", "")
+    severity = lint_action.LintMessageSeverity.ERROR
+
+    return lint_action.LintMessage(
+        range=lint_action.Range(
+            start=lint_action.Position(line=start_line, character=start_column),
+            end=lint_action.Position(line=end_line, character=end_column),
+        ),
+        message=error.get("description", ""),
+        code=error_code,
+        code_description=code_description,
+        source="pyrefly",
+        severity=severity,
+    )
diff --git a/extensions/fine_python_pyrefly/pyproject.toml b/extensions/fine_python_pyrefly/pyproject.toml
new file mode 100644
index 0000000..2ac97b6
--- /dev/null
+++ b/extensions/fine_python_pyrefly/pyproject.toml
@@ -0,0 +1,8 @@
+[project]
+name = "fine_python_pyrefly"
+version = "0.1.0"
+description = ""
+authors = [{ name = "Vladyslav Hnatiuk", email = "aders1234@gmail.com" }]
+readme = "README.md"
+requires-python = ">=3.11, < 3.14"
+dependencies = ["finecode_extension_api==0.3.*", "pyrefly (>=0.30.0,<1.0.0)"]
diff --git a/extensions/fine_python_pyrefly/setup.py b/extensions/fine_python_pyrefly/setup.py
new file mode 100644
index 0000000..7809fb7
--- /dev/null
+++ b/extensions/fine_python_pyrefly/setup.py
@@ -0,0 +1,67 @@
+import atexit
+import shutil
+import sys
+import tempfile
+
+from setuptools import setup
+from setuptools.command.build import build
+from setuptools.command.build_ext import build_ext
+from setuptools.command.build_py import build_py
+from setuptools.command.egg_info import egg_info
+
+# Create a single temp directory for all build operations
+_TEMP_BUILD_DIR = None
+
+
+def get_temp_build_dir(pkg_name):
+    global _TEMP_BUILD_DIR
+    if _TEMP_BUILD_DIR is None:
+        _TEMP_BUILD_DIR = tempfile.mkdtemp(prefix=f"{pkg_name}_build_")
+        atexit.register(lambda: shutil.rmtree(_TEMP_BUILD_DIR, ignore_errors=True))
+    return _TEMP_BUILD_DIR
+
+
+class TempDirBuildMixin:
+    def initialize_options(self):
+        super().initialize_options()
+        temp_dir = get_temp_build_dir(self.distribution.get_name())
+        self.build_base = temp_dir
+
+
+class TempDirEggInfoMixin:
+    def initialize_options(self):
+        super().initialize_options()
+        temp_dir = get_temp_build_dir(self.distribution.get_name())
+        self.egg_base = temp_dir
+
+
+class CustomBuild(TempDirBuildMixin, build):
+    pass
+
+
+class CustomBuildPy(TempDirBuildMixin, build_py):
+    pass
+
+
+class CustomBuildExt(TempDirBuildMixin, build_ext):
+    pass
+
+
+class CustomEggInfo(TempDirEggInfoMixin, egg_info):
+    def initialize_options(self):
+        # Don't use temp dir for editable installs
+        if "--editable" in sys.argv or "-e" in sys.argv:
+            egg_info.initialize_options(self)
+        else:
+            super().initialize_options()
+
+
+setup(
+    name="fine_python_pyrefly",
+    cmdclass={
+        "build": CustomBuild,
+        "build_py": CustomBuildPy,
+        "build_ext": CustomBuildExt,
+        "egg_info": CustomEggInfo,
+    },
+)
\ No newline at end of file
diff --git a/extensions/fine_python_pyrefly/tests/__init__.py b/extensions/fine_python_pyrefly/tests/__init__.py
new file mode 100644
index 0000000..39a7300
--- /dev/null
+++ b/extensions/fine_python_pyrefly/tests/__init__.py
@@ -0,0 +1 @@
+# Tests for fine_python_pyrefly extension
\ No newline at end of file
diff --git a/finecode_dev_common_preset/pyproject.toml b/finecode_dev_common_preset/pyproject.toml
index ed7a1df..38fa669 100644
--- a/finecode_dev_common_preset/pyproject.toml
+++ b/finecode_dev_common_preset/pyproject.toml
@@ -7,7 +7,7 @@ readme = "README.md"
 requires-python = ">=3.11, < 3.14"
 dependencies = [
     "fine_python_aksem @ git+https://github.com/Aksem/fine_python_aksem.git",
-    "fine_python_recommended==0.3.*",
+    "fine_python_recommended==0.4.*",
 ]
 
 [tool.setuptools.package-data]
diff --git a/presets/fine_python_lint/fine_python_lint/preset.toml b/presets/fine_python_lint/fine_python_lint/preset.toml
index ddbb75e..dc81393 100644
--- a/presets/fine_python_lint/fine_python_lint/preset.toml
+++ b/presets/fine_python_lint/fine_python_lint/preset.toml
@@ -7,8 +7,8 @@ handlers = [
     { name = "flake8", source = "fine_python_flake8.Flake8LintHandler", env = "dev_no_runtime", dependencies = [
         "fine_python_flake8==0.2.*",
     ] },
-    { name = "mypy", source = "fine_python_mypy.MypyLintHandler", env = "dev_no_runtime", dependencies = [
-        "fine_python_mypy==0.2.*",
+    { name = "pyrefly", source = "fine_python_pyrefly.PyreflyLintHandler", env = "dev_no_runtime", dependencies = [
+        "fine_python_pyrefly==0.1.*",
     ] },
 ]
 
diff --git a/presets/fine_python_lint/pyproject.toml b/presets/fine_python_lint/pyproject.toml
index 622b6d9..68f0de3 100644
--- a/presets/fine_python_lint/pyproject.toml
+++ b/presets/fine_python_lint/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "fine_python_lint"
-version = "0.3.0"
+version = "0.4.0"
 description = ""
 authors = [{ name = "Vladyslav Hnatiuk", email = "aders1234@gmail.com" }]
 readme = "README.md"
diff --git a/presets/fine_python_recommended/pyproject.toml b/presets/fine_python_recommended/pyproject.toml
index 6d963c4..48de1fc 100644
--- a/presets/fine_python_recommended/pyproject.toml
+++ b/presets/fine_python_recommended/pyproject.toml
@@ -1,11 +1,11 @@
 [project]
 name = "fine_python_recommended"
-version = "0.3.0"
+version = "0.4.0"
 description = ""
 authors = [{ name = "Vladyslav Hnatiuk", email = "aders1234@gmail.com" }]
 readme = "README.md"
 requires-python = ">=3.11, < 3.14"
-dependencies = ["fine_python_format==0.3.*", "fine_python_lint==0.3.*"]
+dependencies = ["fine_python_format==0.3.*", "fine_python_lint==0.4.*"]
 
 [build-system]
 requires = ["setuptools>=64"]