diff --git a/requirements.txt b/requirements.txt
index fbdd29cd..d56b2d7c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -15,3 +15,4 @@ h5netcdf==1.6.1
 impactlab-tools==0.6.0
 p_tqdm==1.4.2
 pyarrow==19.0.1
+numcodecs==0.15.1