[masenf]

The generated StateProvider currently owns every substate reducer, so each delta re-renders that combined provider and recreates the provider elements for all substates. Give each substate its own reducer and provider so a delta only re-renders the providers it touches. Consumer updates continue to depend on their context values.

Dispatchers register into a stable shared registry during the layout phase, before the event loop connects the WebSocket. DispatchProvider's memo depends only on children, since the registry ref has a stable identity.

Validation: 282 compiler tests, all eight router browser cases across development and production modes, and all pre-commit hooks pass. The new browser case extends the existing router app: its initial on-load event updates two sibling substates, and the test verifies both rendered values plus a single received delta containing both updates. It replaces the source-string test that did not establish runtime ordering.

[codspeed]

Merging this PR will not alter performance

✅ 67 untouched benchmarks
⏩ 17 skipped benchmarks¹

---

_{Comparing masenf/memoize-state-provider-separately (8b23c9a) with main (702f675)}

Footnotes

1. 17 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge with no outstanding actionable findings.

Summary

This PR restructures generated client state contexts so each substate has an independent reducer and provider, reducing unnecessary browser re-renders.

• Adds a stable shared dispatcher registry with layout-phase registration before the event loop connects.
• Adds browser coverage for an initial delta updating two sibling substates.
• Revises the performance news fragment to describe the downstream benefit rather than implementation details.

_{Reviews (9) · Last reviewed commit: "Describe state provider performance in u..."}

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}

[masenf]

The final CodSpeed check flagged test_var_access[mutable_dict] (3.22% lower efficiency) with a different-runtime-environment warning. This PR changes the generated state-provider template; the measured Python mutable-proxy code is unchanged. A matched local comparison gave 1.472 ms on main and 1.492 ms here (about 1.36%, below the reported change). These short wall-clock samples cannot establish a causal regression. I have rerun the performance job and am keeping unrelated proxy work out of this PR.

[FarhanAliRaza]

I tested this PR in a real app against a main baseline. The two builds differ only in templates.py.

The app has a root state, sibling substates, a nested substate, a computed var, an event that changes two substates through get_state, a generator event, and two pages with on_load. I added 300 generated substates to make the provider cost visible. A React commit hook counted the components that rendered in each commit and recorded the commit duration.

On main, each delta renders StateProvider and the one consumer. With this PR, each delta renders one SubstateProvider and the one consumer. Consumer renders are the same on both builds. With 310 substates, the median commit duration goes from 1.1 ms to 0.2 ms over 200 clicks.

I also exercised a two-substate delta, a 50-click burst, client navigation between the pages, a hard load on the second page, and a dev hot reload that adds a state var. All deltas dispatched correctly and the browser console stayed clean. A frontend export succeeds.

The requested changes are in the inline comments.

[cubic-dev-ai]

1 issue found across 4 files

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="packages/reflex-base/news/6181.performance.md">

<violation number="1" location="packages/reflex-base/news/6181.performance.md:1">
P3: The fragment names the generated file `utils/context.js`, but the compiler writes it with a JSX extension: `reflex/compiler/utils.py:871` emits `get_web_dir() / (constants.Dirs.CONTEXTS_PATH + constants.Ext.JSX)`, where `CONTEXTS_PATH` is `"utils/context"` (packages/reflex-base/src/reflex_base/constants/base.py:40). Update the fragment to `utils/context.jsx` so the changelog entry matches the shipped file.</violation>
</file>