diff --git a/pyproject.toml b/pyproject.toml
index 4d84c9bc36..1e4dba7d3b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,6 +5,7 @@ requires = [
   "cython",
   "numpy>=1.21.3",
   "torch>=1.10",
+  "mocodo<=4.2.6",
 ]
 build-backend = "setuptools.build_meta"