diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 837cf482a..e9a106536 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -20,7 +20,10 @@ jobs:
     - name: Install apt dependencies
       run: |
         sudo apt update
+        # Install `libopenmpi` for MPI
         sudo apt install openmpi-bin libopenmpi-dev
+        # Install `libhdf5` for `morphio`
+        sudo apt install libhdf5-dev
 
     - name: Install dependencies & self
       run: |