diff --git a/build/fbcode_builder/getdeps/buildopts.py b/build/fbcode_builder/getdeps/buildopts.py
index 5b731b003..90b35b7e2 100644
--- a/build/fbcode_builder/getdeps/buildopts.py
+++ b/build/fbcode_builder/getdeps/buildopts.py
@@ -10,6 +10,7 @@ import os
 import subprocess
 import sys
 import tempfile
+from typing import Optional, Mapping
 
 from .copytree import containing_repo_type
 from .envfuncs import Env, add_path_entry
@@ -18,12 +19,6 @@ from .manifest import ContextGenerator
 from .platform import HostType, is_windows
 
 
-try:
-    import typing  # noqa: F401
-except ImportError:
-    pass
-
-
 def detect_project(path):
     repo_type, repo_root = containing_repo_type(path)
     if repo_type is None:
@@ -312,10 +307,9 @@ def list_win32_subst_letters():
 
 
 def find_existing_win32_subst_for_path(
-    path,  # type: str
-    subst_mapping,  # type: typing.Mapping[str, str]
-):
-    # type: (...) -> typing.Optional[str]
+    path: str,
+    subst_mapping: Mapping[str, str],
+) -> Optional[str]:
     path = ntpath.normcase(ntpath.normpath(path))
     for letter, target in subst_mapping.items():
         if ntpath.normcase(target) == path:
diff --git a/build/fbcode_builder/getdeps/py_wheel_builder.py b/build/fbcode_builder/getdeps/py_wheel_builder.py
index cc783b713..77efe9ba3 100644
--- a/build/fbcode_builder/getdeps/py_wheel_builder.py
+++ b/build/fbcode_builder/getdeps/py_wheel_builder.py
@@ -98,9 +98,7 @@ class PythonWheelBuilder(BuilderBase):
     that can be used by add_fb_python_library()/add_fb_python_executable() CMake rules.
     """
 
-    def _build(self, install_dirs, reconfigure):
-        # type: (List[str], bool) -> None
-
+    def _build(self, install_dirs: List[str], reconfigure: bool) -> None:
         # When we are invoked, self.src_dir contains the unpacked wheel contents.
         #
         # Since a wheel file is just a zip file, the Fetcher code recognizes it as such
@@ -169,9 +167,7 @@ class PythonWheelBuilder(BuilderBase):
         # Run the build
         self._run_cmake_build(install_dirs, reconfigure)
 
-    def _run_cmake_build(self, install_dirs, reconfigure):
-        # type: (List[str], bool) -> None
-
+    def _run_cmake_build(self, install_dirs: List[str], reconfigure: bool) -> None:
         cmake_builder = CMakeBuilder(
             build_opts=self.build_opts,
             ctx=self.ctx,
@@ -187,9 +183,7 @@ class PythonWheelBuilder(BuilderBase):
         )
         cmake_builder.build(install_dirs=install_dirs, reconfigure=reconfigure)
 
-    def _write_cmakelists(self, path_mapping, dependencies):
-        # type: (List[str]) -> None
-
+    def _write_cmakelists(self, path_mapping: List[str], dependencies) -> None:
         cmake_path = os.path.join(self.build_dir, "CMakeLists.txt")
         with open(cmake_path, "w") as f:
             f.write(CMAKE_HEADER.format(**self.template_format_dict))
@@ -221,9 +215,7 @@ class PythonWheelBuilder(BuilderBase):
         with open(output_path, "w") as f:
             f.write(CMAKE_CONFIG_FILE.format(**self.template_format_dict))
 
-    def _add_sources(self, path_mapping, src_path, install_path):
-        # type: (List[str], str, str) -> None
-
+    def _add_sources(self, path_mapping: List[str], src_path: str, install_path: str):
         s = os.lstat(src_path)
         if not stat.S_ISDIR(s.st_mode):
             path_mapping[src_path] = install_path
@@ -236,9 +228,7 @@ class PythonWheelBuilder(BuilderBase):
                 os.path.join(install_path, entry),
             )
 
-    def _parse_wheel_name(self):
-        # type: () -> WheelNameInfo
-
+    def _parse_wheel_name(self) -> WheelNameInfo:
         # The ArchiveFetcher prepends "manifest_name-", so strip that off first.
         wheel_name = os.path.basename(self.src_dir)
         prefix = self.manifest.name + "-"