diff --git a/pyproject.toml b/pyproject.toml
index aa36f8f..55d64a0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -8,7 +8,8 @@ readme = "README.md"
 dependencies = [
     "setuptools",
     "alphapept>=0.5.2",
-    "altair>=5.2.0",
+    # TODO investigate
+    "altair<5.4.0",
     "h5py>=3.10.0",
     "matplotlib>=3.8.2",
     "numba>=0.59.0",