Hey there, thanks for reaching out and welcome to the Streamlit community! 
Segmentation faults like the one you’re seeing (Segmentation fault sudo -E -u appuser /home/adminuser/venv/bin/streamlit “$@”) on Streamlit Community Cloud are often caused by your app exceeding memory/resource limits or by incompatibilities with Python/package versions. This is especially likely if your app was working before and suddenly started crashing, even though it still works locally. Community Cloud has strict resource limits (max ~2.7GB RAM, 2 CPU cores), and memory leaks or large models/files can easily push you over the edge. See the official docs for more on resource limits and common app problems.
My understanding is that the best first steps are: (1) Reboot your app from the workspace or Cloud logs (temporary fix), (2) Optimize your app’s memory usage (use st.cache_data/st.cache_resource, move large data to a database, profile memory), and (3) Check your Python and Streamlit versions—sometimes new releases or dependency conflicts can cause segfaults, so try pinning compatible versions in requirements.txt and avoid using very new Python versions (e.g., 3.13+). If you’re still stuck, please share your requirements.txt and a minimal reproducible example so the community can help debug further! For more troubleshooting, see this FAQ post and the sanity checks guide.
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