diff --git a/server/cli/prepare.py b/server/cli/prepare.py
index b0ff3d43..bd8eb286 100644
--- a/server/cli/prepare.py
+++ b/server/cli/prepare.py
@@ -160,14 +160,7 @@ def prepare(
         sc.pp.neighbors(adata)
 
     def run_louvain(adata):
-        try:
-            sc.tl.louvain(adata)
-        except ModuleNotFoundError:
-            click.echo(
-                "\nWarning: louvain module is not installed, no clusters will be calculated. "
-                "To fix this please install cellxgene with the optional feature louvain enabled: "
-                "`pip install cellxgene[louvain]`"
-            )
+        sc.tl.louvain(adata)
 
     def run_layout(adata):
         if len(unique(adata.obs["louvain"].values)) < 10:
diff --git a/server/requirements-prepare.txt b/server/requirements-prepare.txt
index d1b43def..630015df 100644
--- a/server/requirements-prepare.txt
+++ b/server/requirements-prepare.txt
@@ -1 +1,3 @@
 scanpy>=1.3.7
+python-igraph
+louvain>=0.6
diff --git a/setup.py b/setup.py
index 7987697d..570b4eef 100644
--- a/setup.py
+++ b/setup.py
@@ -39,5 +39,5 @@ setup(
         "Topic :: Scientific/Engineering :: Bio-Informatics",
     ],
     entry_points={"console_scripts": ["cellxgene = server.cli.cli:cli"]},
-    extras_require=dict(prepare=requirements_prepare, louvain=["python-igraph", "louvain>=0.6"], gui=["PySide2>=5.12.3", "cefpython3>=66", "requests"]),
+    extras_require=dict(prepare=requirements_prepare, gui=["PySide2>=5.12.3", "cefpython3>=66", "requests"]),
 )