diff --git a/pyproject.toml b/pyproject.toml
index c8a12d0..8708071 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -45,6 +45,7 @@ test = [
     "scipy",
     "pandas",
     "h5py",
+    "zarr >=2.16.0"
 ]
 
 docs = [