diff --git a/scripts/build_hdf5.py b/scripts/build_hdf5.py
index b6c9af5b..bc66afc3 100644
--- a/scripts/build_hdf5.py
+++ b/scripts/build_hdf5.py
@@ -119,8 +119,9 @@ def hdf5(dirs: T.Dict[str, Path], env: T.Mapping[str, str]):
     # ]
     subprocess.check_call(nice + cmd, cwd=source_dir, env=env)
 
+    cmd = ["make", "-j"]
     # cmd = ["cmake", "--build", BUILDDIR, "--parallel"]
-    # subprocess.check_call(nice + cmd, cwd=source_dir)
+    subprocess.check_call(nice + cmd, cwd=source_dir)
 
     cmd = ["make", "-j", "install"]
     # cmd = ["cmake", "--install", BUILDDIR, "--parallel"]