diff --git a/pyproject.toml b/pyproject.toml
index 162a104..9f5905f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,7 +30,7 @@ build-backend = "setuptools.build_meta"
 where = ["src"]
 
 [tool.setuptools.package-data]
-gaspype = ["data/therm_data.bin"]
+gaspype = ["data/therm_data.bin", "py.typed"]
 
 [project.optional-dependencies]
 dev = [
diff --git a/src/gaspype/py.typed b/src/gaspype/py.typed
new file mode 100644
index 0000000..e69de29