diff --git a/flake.nix b/flake.nix
index 51d808f..e85c8df 100644
--- a/flake.nix
+++ b/flake.nix
@@ -286,7 +286,7 @@
               "pygit2"
               "python-levenshtein"
               "sipyco"
-              "llvmlite"
+              "llvmlite <0.40.0"
               "llvm-tools"
               "lld"
               "tqdm"