diff --git a/.coveragerc b/.coveragerc
deleted file mode 100644
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..0000000000000000000000000000000000000000
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d236a2a68d11d5ad5296c57dcb1e6b3be3e4237a..4637e335ff35bcae7b6a712dad8fb260fd6c451d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,3 +7,8 @@
 * added __len__ to Optional
 * major bugfix in Optional
 * deprecated call_if_nnone
+
+Build system
+------------
+
+* switched to pyproject.toml
\ No newline at end of file