diff --git a/nix/build-all.py b/nix/build-all.py
index d7b7a36e72..e30e3322fa 100644
--- a/nix/build-all.py
+++ b/nix/build-all.py
@@ -348,7 +348,6 @@ if any(f.startswith("occt-") for f in flags):
     OCCT_VERSION = next(f.split('-', 1)[1] for f in flags if f.startswith("occt-"))
 
 print(OCCT_VERSION)
-exit()
 
 if explicit_targets:
     targets = {dep for target in explicit_targets for dep in gather_dependencies(target)}
@@ -889,6 +888,9 @@ if USE_OCCT and "occ" in targets:
     if OCCT_VERSION == "7.8.1":
         patches.append("./patches/occt/no_ExpToCasExe_7_8_1.patch")
 
+    if OCCT_VERSION == "7.9.1":
+        patches.append("./patches/occt/no_ExpToCasExe_7_9_1.patch")
+
     if "wasm" in flags:
         patches.append("./patches/occt/no_em_js.patch")