correctly configured for a platform like Hugging Face Spaces

app.py

@@ -88,10 +88,8 @@ with SinglePageLayout(server) as layout:
                 trame_html.Div(f"QLBM embed failed: {e}", style="padding:8px;color:#b00020;")
 
 if __name__ == "__main__":
-    # If PORT is provided (e.g., Hugging Face), bind on 0.0.0.0; otherwise use localhost
-    env_port = os.environ.get("PORT")
-    port = int(env_port or os.environ.get("HF_PORT", "7860"))
-    host = "0.0.0.0" if env_port else "127.0.0.1"
-    server.start(host=host, port=port, open_browser=False)
+    # For Hugging Face, use the PORT env var and listen on 0.0.0.0
+    port = int(os.environ.get("PORT", 7860))
+    server.start(host="0.0.0.0", port=port, open_browser=False)
 
 

qlbm_trame.py

@@ -0,0 +1,12 @@
+import os
+import sys
+
+# Configure VTK for headless rendering BEFORE any VTK imports
+if os.environ.get("PORT") or os.environ.get("HF_PORT") or os.environ.get("SPACE_ID"):
+    os.environ["MESA_GL_VERSION_OVERRIDE"] = "3.2"
+    os.environ["MESA_GLSL_VERSION_OVERRIDE"] = "150"
+    os.environ["GALLIUM_DRIVER"] = "llvmpipe"
+    # Force VTK to use OSMesa for offscreen rendering
+    os.environ["VTK_DEFAULT_EGL_DEVICE_INDEX"] = "-1"
+
+# ...existing imports...