diff --git a/pyproject.toml b/pyproject.toml
index 5047e19..45d5294 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,5 +1,5 @@
 [build-system]
-requires = ["scikit-build-core", "numpy"]
+requires = ["scikit-build-core", "numpy", "charset-normalizer"]
 build-backend = "scikit_build_core.build"
 
 [project]