visualizing-recomposition-cascades
Visualizing Recomposition Cascades — static blast radius and live heatmap inside the IDE
Passive gutter icons answer "is this composable skippable" (covered by ../using-stability-analyzer-ide-plugin/SKILL.md). The active investigation tools answer two harder questions. The Cascade visualizer walks the static call graph from a root @Composable and shows what else might recompose if the root recomposes. The Live Heatmap subscribes to the device's logcat and renders the actual recomposition counts as block inlays above each instrumented composable in the editor. Together they close the loop between static analysis and runtime evidence.
Both features live inside the same IntelliJ plugin and surface through the right-anchored Compose Stability Analyzer tool window, which has three tabs: Explorer, Cascade, and Heatmap.
When to use this skill
- The developer asks "what gets dragged in if I change this composable" — use the Cascade tab.
- The developer asks "how many times did this recompose during that scroll" or "which composable is hot during this animation" — use the Heatmap tab.
- Triaging a recomposition spike surfaced by
../../recomposition/debugging-recompositions/SKILL.mdand needing the call-site context. - Preparing a refactor and wanting the blast radius before touching a shared composable.
- The user mentions the Cascade tab, the Heatmap tab, recomposition inlays, Analyze Recomposition Cascade, Toggle Recomposition Heatmap, or Clear Recomposition Data.
When NOT to use this skill
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10deferring-state-reads
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