diff --git a/pyproject.toml b/pyproject.toml
index f4045a41..139b73ab 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -64,6 +64,8 @@ metadata.version.provider = "scikit_build_core.metadata.setuptools_scm"
 
 sdist.include = [
     "gaussianfft/_version.py",  # generated by setuptools-scm
+    # Include cached donwloads / compiled dependencies
+    "sources",
 ]
 sdist.exclude = [
     "venv",