diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 5c5ed374d..f1125cc8e 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -209,6 +209,9 @@ jobs:
             - name: Run mypy
               working-directory: api/python/slint
               run: uv run mypy -p tests -p slint
+            - name: Run mypy on slint-compiler
+              working-directory: api/python/compiler
+              run: uv run mypy slint_compiler
             - name: Run ruff linter
               working-directory: api/python/slint
               run: uv tool run ruff check
diff --git a/api/python/compiler/pyproject.toml b/api/python/compiler/pyproject.toml
index 473c1eb34..34b86d49c 100644
--- a/api/python/compiler/pyproject.toml
+++ b/api/python/compiler/pyproject.toml
@@ -19,3 +19,14 @@ Tracker = "https://github.com/slint-ui/slint/issues"
 
 [project.scripts]
 slint-compiler = "slint_compiler:main"
+
+[dependency-groups]
+dev = ["mypy>=1.15.0"]
+
+[tool.mypy]
+strict = true
+disallow_subclassing_any = false
+
+[[tool.mypy.overrides]]
+module = ["cached_path.*"]
+follow_untyped_imports = true
diff --git a/api/python/compiler/slint_compiler/__init__.py b/api/python/compiler/slint_compiler/__init__.py
index 217c82cb8..23ed38ff3 100644
--- a/api/python/compiler/slint_compiler/__init__.py
+++ b/api/python/compiler/slint_compiler/__init__.py
@@ -10,7 +10,7 @@ import os
 from importlib.metadata import version, PackageNotFoundError
 
 
-def main():
+def main() -> None:
     try:
         package_version = version("slint-compiler")
         # Strip alpha/beta from for example "1.13.0b1"
@@ -58,7 +58,7 @@ def main():
     local_path = cached_path.cached_path(
         url_and_path_within_archive, extract_archive=True
     )
-    args = [local_path]
+    args = [str(local_path)]
     args.extend(sys.argv[1:])
     subprocess.run(args)