diff --git a/src/numpy-stubs/testing/_private/__init__.pyi b/src/numpy-stubs/testing/_private/__init__.pyi
new file mode 100644
index 00000000..e69de29b
diff --git a/src/numpy-stubs/testing/_private/extbuild.pyi b/src/numpy-stubs/testing/_private/extbuild.pyi
new file mode 100644
index 00000000..609a45e7
--- /dev/null
+++ b/src/numpy-stubs/testing/_private/extbuild.pyi
@@ -0,0 +1,25 @@
+import pathlib
+import types
+from collections.abc import Sequence
+
+__all__ = ["build_and_import_extension", "compile_extension_module"]
+
+def build_and_import_extension(
+    modname: str,
+    functions: Sequence[tuple[str, str, str]],
+    *,
+    prologue: str = "",
+    build_dir: pathlib.Path | None = None,
+    include_dirs: Sequence[str] = [],
+    more_init: str = "",
+) -> types.ModuleType: ...
+
+#
+def compile_extension_module(
+    name: str,
+    builddir: pathlib.Path,
+    include_dirs: Sequence[str],
+    source_string: str,
+    libraries: Sequence[str] = [],
+    library_dirs: Sequence[str] = [],
+) -> pathlib.Path: ...