optimizing-streamlit-performance

Streamlit apps rerun the entire script on every widget interaction, causing heavy re-computations and slow rendering. This Skill addresses the problem by applying caching, fragment isolation, and widget layout strategies to control reruns and boost responsiveness.

st.cache_data works by storing the results of expensive data-loading or computation functions, so Streamlit can retrieve cached outputs instantly instead of recomputing them on every script rerun, significantly optimizing app performance.

You can use st.fragment to isolate specific UI components, so that interactions within that fragment only trigger a local rerun instead of executing the entire Streamlit script, limiting unnecessary reruns and speeding up rendering.

The best way to optimize Streamlit performance is combining st.cache_data for caching expensive functions, st.fragment for isolating UI reruns, and a thoughtful widget strategy to control data loading and dashboard responsiveness.

Yes, you can retrofit an existing Streamlit app by applying st.cache_data to expensive functions, wrapping UI components in st.fragment, and adjusting layout decisions to reduce script-wide reruns and speed up rendering.