diff -urN a/pyproject.toml b/pyproject.toml
--- a/pyproject.toml	2021-04-16 15:26:19.000000000 +0200
+++ b/pyproject.toml	2021-11-08 21:38:57.758890447 +0100
@@ -2,7 +2,7 @@
 requires = [
     "setuptools",
     "wheel",
-	"numpy <= 1.19.3",
+    "numpy",
     "cython"
 ]
 build-backend = "setuptools.build_meta"