diff --git a/pyproject.toml b/pyproject.toml
index 65f639b..2b84bcd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,6 +30,7 @@ homepage = "https://github.com/greenbone/autohooks-plugin-mypy"
 repository = "https://github.com/greenbone/autohooks-plugin-mypy"
 packages = [
   { include = "autohooks" },
+  { include = "tests", format = "sdist"},
 ]
 
 [tool.poetry.dependencies]