v0.9.0 Pre-release thread

[adhami3310]

Please report any problems you encounter in this discussion thread or as separate issues on reflex-dev/reflex.

pip install 'reflex~=0.9.0a'

Schedule

2026-04-10 12:20 PT: 0.9.0a2 pre-release published for testing
2026-04-13: Planned Public release of 0.9.0

Release Notes

What's Changed

• provide event for redis state expiry by @adhami3310 in provide event for redis state expiry #6194
• Support FunctionVar handlers in EventChain rendering by @FarhanAliRaza in Support FunctionVar handlers in EventChain rendering #6188
• feat: add chunked file upload support Streaming Upload API (rx.upload_files_chunk) by @FarhanAliRaza in feat: add chunked file upload support Streaming Upload API (rx.upload_files_chunk) #6190
• Add in-memory state expiration to StateManagerMemory by @FarhanAliRaza in Add in-memory state expiration to StateManagerMemory #6201
• feat: add experimental memo decorator for JS-level component and function memoization by @FarhanAliRaza in feat: add experimental memo decorator for JS-level component and function memoization #6192
• Add chunked upload documentation for rx.upload_files_chunk by @FarhanAliRaza in Add chunked upload documentation for rx.upload_files_chunk #6259
• ENG-9028: Move event queue to backend by @masenf in ENG-9028: Move event queue to backend #6267
• remove pydantic sqlmodel alembic dep by @adhami3310 in remove pydantic sqlmodel alembic dep #6293
• add sitemap slash configuration by @adhami3310 in add sitemap slash configuration #6291
• ENG-8961: Single port is only prod option by @adhami3310 in ENG-8961: Single port is only prod option #6297

Performance Improvements

• fix: avoid eagerly copying uploaded files into memory by @FarhanAliRaza in fix: avoid eagerly copying uploaded files into memory #6174
• Cache expensive introspection calls in pyi_generator for faster stub generation by @FarhanAliRaza in Cache expensive introspection calls in pyi_generator for faster stub generation #6187
• do inspect signature once by @adhami3310 in do inspect signature once #6197
• define _compile_stateful_components as an external by @adhami3310 in define _compile_stateful_components as an external #6198
• do not compile stateful components in dev mode by @adhami3310 in do not compile stateful components in dev mode #6199
• skip duplicate DynamicRouteVar by @adhami3310 in skip duplicate DynamicRouteVar #6202
• avoid validating app when running in backend only by @adhami3310 in avoid validating app when running in backend only #6203

Bugfixes

• Fix race conditions in StateManagerRedis lock detection by @masenf in Fix race conditions in StateManagerRedis lock detection #6196
• reflex.event: revert future annotation changes by @masenf in reflex.event: revert future annotation changes #6254
• Fix buffered upload handler not cancelling on client disconnect by @FarhanAliRaza in Fix buffered upload handler not cancelling on client disconnect #6307
• fix: set_focus/blur_focus args stripped by get_handler_args for stateless handlers by @FarhanAliRaza in fix: set_focus/blur_focus args stripped by get_handler_args for stateless handlers #6314
• Serve _upload files with content-disposition: attachment by @masenf in Serve _upload files with content-disposition: attachment #6303
• fix: collect imports from components in props in _get_all_imports() by @lawrence3699 in fix: collect imports from components in props in _get_all_imports() #6317

Docs

• implement reflex docgen by @adhami3310 in implement reflex docgen #6200
• ENG-9032: move framework docs into framework repo by @adhami3310 in ENG-9032: move framework docs into framework repo #6206
• Expose docs through reflex docgen by @adhami3310 in Expose docs through reflex docgen #6257
• make reflex state import dynamic by @adhami3310 in make reflex state import dynamic #6258
• remove all pcweb references from the docs by @adhami3310 in remove all pcweb references from the docs #6263
• add back images for readme by @adhami3310 in add back images for readme #6265
• Fix cond typing by @adhami3310 in Fix cond typing #6279
• Make reflex init and docs uv-first by @GautamBytes in Make reflex init and docs uv-first #6287
• Add docs app by @carlosabadia in Add docs app #6299
• Add reflex-ui and integrations docs to packages by @carlosabadia in Add reflex-ui and integrations docs to packages #6302
• Update docs sidebar text color by @carlosabadia in Update docs sidebar text color #6309
• Update posthog script by @carlosabadia in Update posthog script #6315
• Add posthog recordings and events by @carlosabadia in Add posthog recordings and events #6310
• Remove image zoom in how reflex works doc by @carlosabadia in Remove image zoom in how reflex works doc #6276

Chores

• 090dev by @adhami3310 in 090dev #6182
• README.md: Add responsive logo for light and dark themes by @masenf in README.md: Add responsive logo for light and dark themes #6253
• export modules for plugins by @adhami3310 in export modules for plugins #6261
• make the ci better at not install reflex deps for reflex-web by @adhami3310 in make the ci better at not install reflex deps for reflex-web #6262
• reflex core is typed by @adhami3310 in reflex core is typed #6271
• Add wildcard ignore and pragma: no cover for compat shims by @masenf in Add wildcard ignore and pragma: no cover for compat shims #6275
• ENG-9277: Add AI builder, Entreprise and hosting docs by @carlosabadia in ENG-9277: Add AI builder, Entreprise and hosting docs #6277
• Rename reflex core to reflex base by @adhami3310 in Rename reflex core to reflex base #6281
• specify directories for publish by @adhami3310 in specify directories for publish #6282
• improve pypi directory handling by @adhami3310 in improve pypi directory handling #6283
• publish dist star by @adhami3310 in publish dist star #6284
• Codspeed benchmark for backend state event processing by @masenf in Codspeed benchmark for backend state event processing #6290
• Remove 090 deprecations by @adhami3310 in Remove 090 deprecations #6292
• Exclude old-style imports when they will be replaced with subpackage imports by @masenf in Exclude old-style imports when they will be replaced with subpackage imports #6294
• ENG-9212: integration socket.dev in OSS integration tests by @masenf in ENG-9212: integration socket.dev in OSS integration tests #6280
• Bump requests from 2.32.5 to 2.33.0 in the uv group across 1 directory by @dependabot[bot] in Bump requests from 2.32.5 to 2.33.0 in the uv group across 1 directory #6251
• reflex-web CI uses local reflex version by @masenf in reflex-web CI uses local reflex version #6298
• remove git https pyproject by @adhami3310 in remove git https pyproject #6306
• remove flexdown completely by @adhami3310 in remove flexdown completely #6308
• Update some reflex ui components by @carlosabadia in Update some reflex ui components #6311
• Add page whitelist instructions to README for faster docs app dev builds by @carlosabadia in Add page whitelist instructions to README for faster docs app dev builds #6313
• pyi_generator regression tests by @masenf in pyi_generator regression tests #6318
• More pyi_generator tweaks by @masenf in More pyi_generator tweaks #6319
• Usability improvements for generated type hints by @masenf in Usability improvements for generated type hints #6300

New Contributors

• @FarhanAliRaza made their first contribution in fix: avoid eagerly copying uploaded files into memory #6174
• @GautamBytes made their first contribution in Make reflex init and docs uv-first #6287
• @lawrence3699 made their first contribution in fix: collect imports from components in props in _get_all_imports() #6317

Full Changelog: v0.8.28...v0.9.0a2