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Reflex Changelog

v0.10.0 (2026-10-08)

Breaking Changes

Python and dependencies

  • Drop support for Python 3.10, which reaches end of life in October 2026. Reflex now requires Python 3.11 or newer. (#7449)
  • reflex[db] allows SQLModel 0.0.45 and later, which stores a plain datetime field as UTC: writes and filters need timezone-aware values and reads return aware ones. To keep naive datetimes, declare the field with sa_type=DateTime(timezone=False) or pin sqlmodel<0.0.45, as described in Datetimes and SQLModel upgrades. (#7462)

State

  • Reading a backend var on a state class (State._items) now returns its Field descriptor instead of the var's default value. Passing it to a component, which used to bake the default into the frontend, now raises ChildrenTypeError as a child or TypeError: Unsupported type <class 'reflex_base.vars.base.Field'> for LiteralVar. as a prop. To keep baking in the default, pass State._items.default_value() instead; to make the value reactive, declare a frontend var or computed var and pass that. See Upgrading to Reflex 0.10. (#7312)
  • Assigning a state var through its state class, such as State.count = 10, raises TypeError instead of replacing the var; so do pytest's monkeypatch.setattr and unittest.mock.patch.object on a var. Change a default with State.__fields__["count"].set_default(10), patch the field in tests, and declare class-level configuration as ClassVar. See Upgrading to Reflex 0.10. (#7516)
  • Mutable values provided as state var defaults are deep-copied when assigned at class creation time or passed to set_default, so later changes to the original object no longer reach new sessions. A module-level list filled in after the class statement, such as options: list[str] = OPTIONS followed by OPTIONS.append(...), now starts every session empty: fill it before the class is defined, or declare default_factory=lambda: list(OPTIONS). (#7519)
  • In a background task, calling a state-modifying handler inherited from a parent state, or writing an inherited var, outside async with self now raises ImmutableStateError like any other state change. See Upgrading to Reflex 0.10. (#7312)
  • Assigning an undeclared state attribute still raises SetUndefinedStateVarError outside of prod mode, but no longer in prod. The internal class maps backend_vars, inherited_vars and inherited_backend_vars, get_skip_vars() and the instance _backend_vars are removed: use get_fields(), whose fields know the state they belong to. (#7312)
  • Instances of Reflex 0.9 and 0.10 can no longer share a Redis or disk state store. A 0.10 instance loads state saved by 0.9, but a 0.9 instance discards state saved by 0.10, so a rolling deploy that runs both versions, or a rollback to 0.9 against the same store, resets the sessions that reach the older instance. Upgrade every instance of an app together, and clear the store (or start a fresh one) when rolling back. (#7494)

CLI

  • Remove the reflex component CLI (init, build, share, install) and the CustomComponents constants; running reflex component now points to the replacements. Wrap React libraries directly in your app as described in the wrapping React docs, and start reusable component packages from the component template, which builds, tests, and publishes them with standard Python tooling. (#6425, #7497)

Deprecations

  • Deprecate State.router.headers.cookie and State.router.headers["cookie"] in components; both now render an empty string. Use rx.Cookie for cookies that need to be accessible to the frontend. (#7360)

Features

  • A substate may now declare a var or computed var with the same name as an inherited var: it gets an independent one of its own, instead of raising BaseVarShadowsInheritedVarError or ComputedVarShadowsBaseVarsError. A dynamic route arg only conflicts with a var of the state it is installed on. (#7312)
  • The duration settings read by the app and the state managers take a unit suffix: SQLALCHEMY_POOL_TIMEOUT, REFLEX_SOCKET_INTERVAL and REFLEX_SOCKET_TIMEOUT accept values such as 2m, and REFLEX_AUTO_RELOAD_COOLDOWN, REFLEX_OPLOCK_HOLD_TIME and REFLEX_STATE_MANAGER_DISK_DEBOUNCE replace the _MS/_SECONDS names, which still work with a deprecation warning until 1.0. A bare number is read as seconds. (#7138)
  • Set REFLEX_REDIS_MAX_CONNECTIONS to cap each Redis client's connection pool (the state manager, the token manager and the health check each use their own client). Once a pool reaches the cap, requests wait up to REFLEX_REDIS_POOL_TIMEOUT (default 2s, which must be above 0 and below the configured state-lock lifetime) for a free connection instead of opening new ones. (#7179)

Bug Fixes

State and events

  • Stop sending request cookies, including HttpOnly cookies, and standard authorization, Cloudflare Access, OAuth2 Proxy, AWS ALB, and Google IAP credential headers to frontend router data. On-load events no longer copy request router metadata to the frontend; server-side access to request headers is unchanged. (#7360)
  • Defaults are no longer part of the saved-state schema, so changing one keeps state saved by this release or later loadable. A browser storage var annotated with a storage type, such as rx.Field[rx.LocalStorage], and declared with a default_factory compiles with the storage options the factory produces, and reset() restores the factory's value. (#7461)
  • Assigning a double-underscore private attribute on a state (self.__counter = 1) from a mixin, a base, or a class whose name starts with an underscore no longer raises SetUndefinedStateVarError in dev mode. Private names not explicitly declared with rx.field() are plain Python attributes: vars do not update in response to them. (#7465)
  • In a background task on a substate, in-place changes to a mutable var inherited from a parent state (like self.items.append(...)) are now sent to the client and persisted. (#7312)
  • A page URL with a self query parameter (e.g. /post?self=1), or a request header named self, no longer crashes router data parsing and leaves the page unhydrated. (#7324)
  • A state stored in Redis that can no longer be unpickled, for example because a deploy moved or deleted a class held in a state var, is now replaced with a fresh state like a schema mismatch, instead of failing every event from that tab until the Redis key expires. (#7329)
  • The memory and disk state managers now free expired session states right away instead of waiting for a garbage collection pass, and the disk state manager no longer keeps a lock for every expired session. (#7318)
  • Fix a race with REFLEX_OPLOCK_ENABLED where an instance could take an opportunistic lease before its Redis lock notifications were active, making other instances wait out the full hold time for the same token. (#7372)
  • Fix TypeError: refs._client_state_set... is not a function when a component sets a global rx._x.client_state value before any component reading .value has mounted, such as when the reader sits behind an rx.cond. (#7286)
  • Preserve ID-based form controls through automatic memoization while excluding IDs on non-controls from submissions. (#7227)

Database

  • The db extra now installs greenlet, which SQLAlchemy 2.1 no longer pulls in on its own, so rx.Model, rx.session() and the reflex db commands work on a fresh pip install reflex[db] instead of failing with ImportError: The SQLAlchemy asyncio module requires that the Python 'greenlet' library is installed. (#7466)
  • Fixed reflex db makemigrations/migrate crashing with CompileError when autogenerating a migration that adds a column with a callable default (e.g. default_factory=datetime.now or default=uuid.uuid4) to an existing table; callable defaults are now evaluated before being carried as a SQL server_default. (#6706)
  • reflex db commands only require sqlalchemy and alembic, so apps that use plain SQLAlchemy models without sqlmodel can run migrations again. (#7322)
  • reflex db commands run without the db extra installed now exit with the "pip install reflex[db]" message instead of a raw traceback. (#7259)

CLI, build and serving

  • Serve valid dynamic-route URLs (e.g. /articles/7) with HTTP 200 instead of 404 when loaded directly in self-hosted prod static serving, reserving 404 for genuinely unknown paths. (#6996)
  • reflex run now stops its frontend on SIGTERM and SIGINT without a TTY, while keeping frontend workers in the CLI process group so a hard kill also stops them. (#7328)
  • reflex run --json now emits every output line as a JSON record: print() output from the app, subprocess output, and worker tracebacks (as one record with an exception field) no longer break the JSON-lines stream. (#7350)
  • Fix stylesheet edits in assets/ not applying in dev mode until a manual reload. (#7317)
  • Avoid reinstalling frontend packages on every compile or hot reload when bun or npm only changes the formatting of package.json. (#7236)
  • When a project keeps using npm because reflex.lock/ only has package-lock.json (for example after a run with REFLEX_USE_NPM=1), Reflex now logs why and how to switch back to bun with REFLEX_USE_NPM=0. (#7093)
  • Reflex now checks the Node.js version before running npm, so an unsupported Node.js no longer leaves npm lockfiles behind that switch later runs to npm. (#7210)
  • An editable install (uv sync, pip install -e .) no longer overwrites .pyi stubs that the checkout already has. A checkout missing any of them still gets them generated. (#7303)
  • On Windows, the development backend no longer closes its listening socket twice when it releases the port, which could close another socket that had reused the handle and make it fail with OSError: [WinError 10038]. (#7348)
  • Stop logging asyncio.CancelledError: lifespan_cleanup as an error when a running coroutine lifespan task is cancelled at backend shutdown or hot reload. (#7392)

Testing

  • AppHarness now forgets the states of every module of the app's package when it stops, not only those of the app module, so a state defined elsewhere in the app (for example one using rx.dynamic) no longer breaks the next app started in the same test process. (#7359)

Performance

  • Speed up first page loads by combining hydration with the websocket connect and sending only values that differ from compiled defaults. Reduce Redis state-tree read/write overhead and avoid repeated class metadata computation in apps with many states. (#7064)
  • Reading a state var is about 4x faster, and setting one about 7x faster (15x in prod mode): vars, computed vars and event handlers are now descriptors on the state class that declares them, instead of every attribute access going through BaseState.__getattribute__. (#7312)
  • Process events with less CPU on the backend: iterating, sorting and reading list and dataclass state values costs 25–75% less, and the redis state manager writes the changed states of a session in one round trip. (#7370)
  • Apps that define an rx.SharedState no longer pay extra per-event work for events that change no shared state. (#7237)
  • Compile memoized components faster by reusing unchanged memo bodies instead of rendering them again. (#7123)

Documentation

  • Add an Upgrading to Reflex 0.10 guide covering the changes most likely to break an existing app, with the fix for each. (#7496)
  • Document the dict form for rx.toast action and cancel props instead of referencing the non-public ToastAction class. (#7327)

Miscellaneous

  • Allow wrapt 2.4 and 2.5. (#7424)

v0.9.12 (2026-09-21)

Breaking Changes

  • The root state gained five base vars holding the router data: rx_router_session, rx_router_headers, rx_router_page, rx_router_url and rx_router_route_id. A substate that declares one of these names now raises BaseVarShadowsInheritedVarError, the same error any other shadowed inherited var raises, and must rename its field. State.router itself is unchanged. (#7068)
  • Declaring a substate var that shadows a var inherited from a parent state now raises BaseVarShadowsInheritedVarError at class creation. Such a declaration was silently ignored — reads and writes resolved to the parent's var and class-level access returned the raw default instead of a reactive Var. Rename the substate var to fix the error. (#7077)
  • State vars, event handlers, and dynamic route arguments now reject names reserved by framework methods and bookkeeping before registration. Rename conflicting members. (#7136)
  • state.dict() and the state deltas no longer carry a single router entry: the root state now serializes rx_router_session, rx_router_headers, rx_router_page, rx_router_url and rx_router_route_id instead (each with the usual field-marker suffix). Code that read or rewrote the router entry of a state dict or delta — for example to redact request headers before returning state over an API — must read those five entries instead. State.router itself is unchanged for app code. (#7215)

Deprecations

  • Declaring a computed var dependency on the router var (deps=["router"]) is deprecated; depend on the router Var instead, e.g. deps=[State.router.url] for a single field or deps=[State.router] to keep tracking all of them. (#7068)

Bug Fixes

  • Fix stateful inputs under rx.form.control(..., as_child=True) so they receive the parent form's attributes and their values appear in submitted form data. (#6850)
  • Allow State Vars for page titles and descriptions in @rx.page and compiled metadata. (#6923)
  • Stopping reflex run with SIGTERM no longer reports "Starting frontend failed with exit code 143" and now exits cleanly. (#6981)
  • Preserve relationship serialization and database usage accounting for apps that use SQLModel directly, without loading unused database integrations. (#7049)
  • Preserve prerendered pages when asset directories collide with routes under frontend_path, and compress the final merged output. (#7078)
  • Generated .pyi stubs now type a prop declared as a union — content: Var[str] | Component, say — as optional, matching the None default that create() gives every prop. Type checkers previously reported the generated signature itself as an error. (#7080)
  • Subclassing rx.Model (e.g. class Item(rx.Model, table=True)) without the db extra installed now raises the guided "pip install reflex[db]" ImportError instead of a bare TypeError from __init_subclass__. (#7083)
  • Backend-only development runs no longer leave a compile-skip marker that can cause the next full run to skip frontend compilation. (#7089)
  • Persist bundled-library metadata for backend-only workers so state hydration can serialize values that reference libraries included in the frontend build. (#7096)
  • Keep the development backend port open while hot reload restarts the worker, so requests made during a reload wait for the new worker instead of being refused. (#7114)
  • Fixed local package specifiers such as @masenf/hello-react@../hello-react and @masenf/hello-react@../hello-react.tgz being truncated at the first slash (to @masenf/hello-react@..) before reaching the package manager, so wrapping a React package from a local directory or archive now installs correctly. (#7117)
  • Switching between bun and npm (REFLEX_USE_NPM) no longer leaves reflex.lock/ in a state that makes the next run fail with bun install --frozen-lockfile: lockfile had changes. Only the lockfile of the package manager that actually ran is kept. (#7129)
  • Keep saving state to disk and Redis when a state defines a var named _get_was_touched. (#7132)
  • Apps no longer crash at startup with AttributeError: 'method' object attribute '__call__' is read-only when ASGI instrumentation that wraps middleware is active, such as sentry-sdk's Starlette integration. (#7139)
  • Fix backend startup crashes from concurrent or truncated stateful-page marker writes. Markers are replaced atomically, remain readable by separate backend users, and are rebuilt when missing or corrupt; dry-run compilation leaves them unchanged. (#7142)
  • Match routes that start with the frontend_path text, such as /apple under frontend_path="/app", instead of treating them as 404. (#7153)
  • Flush OpenTelemetry compile spans before the isolated initial development compile worker exits. (#7155)
  • Fixed StateManagerDisk.set_state to persist and cache state instances that were not obtained from get_state, and debounced writes now flush the latest supplied value instead of the first one queued. (#7159)
  • Fix @rx.memo components dropping the app wraps their body requires. Providers requested by a nested child, or through var data as rx.upload's UploadFilesProvider is, now reach the app root — so a provider-backed component behaves the same inside a memo as inlined into the page. (#7176)
  • Reuse one long-lived Redis client for the /_health endpoint instead of opening and closing a new TCP connection on every probe. (#7187)
  • Emit Granian lifecycle logs as JSON records when Reflex JSON logging is enabled, keeping reflex run --json stdout valid JSON lines. (#7193)
  • Avoid crash when node is not installed (error: restartWithMergedOptions() was called, but the process has already been restarted.). (#7202)
  • type(rx.State) is reflex.vars.BaseStateMeta again, so a state declared with its own metaclass derived from BaseStateMeta (class MyState(rx.State, metaclass=MyMeta)) no longer raises TypeError: metaclass conflict. The reserved-state-name validation is unchanged: it now runs from BaseStateMeta itself for every subclass of rx.State. (#7215)
  • An @rx.var(cache=False) value that a downstream get_delta override keeps out of the delta is now delivered as soon as the override stops withholding it, instead of being deduplicated away until the value changes again. Uncached var values only count as sent to the client once the delta that carries them is actually delivered. (#7216)
  • Release the development backend port again when no worker can serve it, so requests fail fast while the app module raises on import and after the server shuts down, instead of waiting in the accept backlog until the client times out. (#7217)
  • Keep app wraps registered below the "Built with Reflex" badge in the rendered page. In production builds with the badge on, the badge swallowed every lower-priority app wrap, so rx.data_editor's <div id="portal" /> never reached the DOM and its overlay cell editors — including the new image preview — could not open. (#7218)
  • Fix nested router mutations bypassing background-task locks and read-only state proxies. Writes through self.router now enforce the same mutation guards as direct state-field access. (#7230)

Performance

  • @rx.var(cache=False) vars now remember what they last sent to the frontend. They are still recomputed on every state update, but the value is only included in the delta when it actually changed, so an uncached var whose value stays the same no longer causes needless network traffic and re-renders. (#6946)
  • Reduce development startup and reload time and memory by deferring unused database, admin, and compiler imports in the backend launcher and state mutation tracking, and by avoiding redundant app preloads in spawned Granian supervisors. (#7049)
  • Store router data in separate base vars (session, headers, page, url, route_id) so a navigation delta only re-sends the fields that changed instead of the whole router, and gather the connection-scoped router data (headers, client IP, session id) once at connect time rather than on every event. State.router is unchanged for app code.
  • The page URL is also persisted as the URL itself rather than as its parsed pieces: ReflexURL and URLData re-split on the way out of the state store instead of writing scheme, netloc, origin, path, query, query parameters and fragment alongside the href on every state write. (#7068)
  • Preload the global stylesheet so browsers can discover render-blocking CSS alongside early resource hints. (#7078)
  • Honor frontend_lazy_bundled_libraries when compiling the app root so optional dynamic-component namespaces do not force their full exports into every page's initial bundle. (#7078)
  • Reduce reflex run and reflex export memory: the vite/react-router processes no longer keep their dependency pre-bundling arena resident (MIMALLOC_ARENA_EAGER_COMMIT=0, overridable from the environment), and error telemetry is sent through urllib so backend workers never import httpx. (#7112)
  • Speed up compilation by reading only the props a component sets, caching literal Var dispatch by value type, and trimming render and app-wrap bookkeeping. (#7121)
  • Share one event chain per handler and trigger across call sites, and reuse memoized event wrappers by chain identity during compilation. (#7122)

Documentation

  • Refresh the docker-example deployments for current Reflex and consolidate them into production, production-compose, and app-platform-backend, with smaller images, clean SIGTERM shutdown, and no build tooling at runtime. The two-port example is gone since prod mode now serves the frontend and backend on one port; the self-hosting docs are updated to match. (#7140)

v0.9.11 (2026-09-11)

Breaking Changes

  • State deltas may emit state entries and variable keys in a different order. Values are unchanged, but downstream snapshots or tests comparing serialized deltas as text may need updating; compare parsed JSON objects or normalize key order instead. (#7087)

Features

  • Propagate a frontend traceparent into event spans, count websocket connections and message sizes, and wrap the ASGI app when the reflex-otel instrumentor is active. (#6227)

Bug Fixes

  • A backend var whose name is annotated on a state now takes the default declared by a field() on a base class instead of silently becoming None, and an error raised by that field's default_factory surfaces instead of being swallowed. (#6812)
  • State classes no longer resolve descriptors while being constructed, so a hybrid property's frontend var is no longer built against a half-built class. (#6812)
  • Assigning to a state attribute backed by a property (including a hybrid_property) now runs its setter instead of raising SetUndefinedStateVarError. (#6812)
  • Telemetry events are now collected under the submitting thread's registration context, so the background worker reuses the config the app already loaded instead of re-importing rxconfig.py (and mutating sys.path) off-thread. (#6960)
  • Make reflex.testing importable without test-only dependencies and provide a testing extra for AppHarness. (#6974)
  • Mutable proxies over dataclass state values now carry the wrapped type's __dataclass_params__ and __match_args__ on their class alongside __dataclass_fields__, so code that inspects a dataclass through the class — reading the frozen/eq flags or the positional field names after dataclasses.is_dataclass — no longer raises AttributeError on a proxied value. (#7014)
  • AdminDash now works with starlette-admin 1.0, which renamed the SQLAlchemy Admin(engine=...) argument to session_provider. Both starlette-admin 0.x and 1.x are supported. (#7019)
  • Compiling an app from several processes against one working directory — pytest-xdist workers, parallel builds, or containers sharing a bind mount — no longer aborts with FileNotFoundError or FileExistsError while linking a rx.asset(shared=True) file into assets/external/. A shared asset whose link already points at a different file is repointed at the asset rather than left alone. (#7039)
  • reflex run --env prod and reflex export no longer fail with FileNotFoundError when frontend_path is set and route prerendering is disabled (REFLEX_SSR=false), and no longer fail on Windows with cannot instantiate 'PosixPath' whenever frontend_path is set. (#7044)
  • Generate the frontend context module as utils/context.jsx so reflex run hot updates keep the state providers mounted; a stale utils/context.js is removed on the next compile. (#7071)
  • Fix rx.AdminDash pages failing with NoMatchFound by preserving named route lookup through the application's context middleware. (#7107)
  • Give forked backend workers distinct socket-owner identities so Redis can deliver backend-initiated state updates to clients connected to another worker. (#7108)
  • Preserve explicit bundle_library() registrations through frontend compilation and automatically bundle imports used by initial-state components. Explicitly registered component subpaths can first appear after an event, and initial components such as Lucide icons no longer need a separate registration. (#7109)

Performance

  • Clear auto-memoization naming caches after compiling app. (#6947)
  • New opt-in dev-server knobs: REFLEX_DEV_PROD_REACT=1 serves React's production build under the Vite dev server (navigation CPU on a large app 54 → 36 ms, prod build 24 ms; edits become a full reload since Fast Refresh needs dev React), and REFLEX_VITE_WARMUP_ROUTES=1 pre-transforms route modules at startup so the first visit to a page no longer waits on Vite (105–131 → 43–69 ms, or 20–32 ms with both). (#7021)
  • Trimmed the framework overhead around every event handler: the state fast-paths its own bookkeeping attributes, foreground handler tasks start eagerly on Python 3.12+, the computed-var expiry check only looks at interval vars, route matching is memoized per path, and socket.io handlers run inline. About 28% less CPU per trivial event and 20% more events per second per worker under concurrent load. (#7025)
  • Reduce CLI startup time by loading component and cloud command implementations only when invoked, and avoid frontend package reinstalls after backend-only config changes. (#7050)
  • Avoid repeated PyPI requests by caching successful latest-version checks for 24 hours and throttling failed checks for one hour. (#7050)

Miscellaneous

  • Allow wrapt 2.2 and 2.3. (#7019)

v0.9.10 (2026-09-01)

Bug Fixes

  • Shared state updates now reach linked clients connected to other backend instances — the fan-out previously skipped any client whose websocket was not connected to the instance processing the event, so with redis and multiple workers only same-instance clients received live updates. (#6934)
  • Allow static IDs on document-root head components without generating React hooks. (#7005)

v0.9.9 (2026-08-28)

Breaking Changes

  • pip install reflex no longer installs pydantic; pydantic model support activates when it is installed. Use the new reflex[pydantic] extra (or reflex[db]) to keep it. (#6786)
  • The compiled frontend now targets React Router 8.3.0 (from 7.18.2), and Reflex requires Node 22.22.0 or newer as a result. Apps on the default generated setup need no rxconfig.py or app code changes. One change is required if you wrote a custom component against react-router-dom: that package no longer exists upstream and is no longer installed, so library = "react-router-dom" must become react-router (or react-router/dom for RouterProvider/HydratedRouter). (#6854)
  • A RegistrationContext can only be associated with a single App instance, so creating a second bare rx.App() in one process now raises ReflexRuntimeError (0.9.8 allowed it); use a fresh RegistrationContext (e.g. RegistrationContext.fork()) to create multiple apps. (#6382)

Deprecations

  • reflex.components.dynamic.bundled_libraries and DEFAULT_BUNDLED_LIBRARIES are deprecated (removal in 1.0) but keep working, resolving against the active RegistrationContext. Use RegistrationContext.ensure_context().bundled_libraries to read the list, or bundle_library() / reset_bundled_libraries() to modify it. (#6967)
  • reflex.page.DECORATED_PAGES is deprecated (removal in 1.0) but keeps working, resolving to a mapping of the app name to the active RegistrationContext's page registrations. Use RegistrationContext.ensure_context().decorated_pages instead. (#6985)

Features

  • The current App, the loaded Config, @rx.page registrations, and the bundled-library registry are now scoped to the active RegistrationContext instead of module-level globals, so multiple apps (and test harnesses) can coexist in one process without leaking registrations into each other. (#6382)
  • Report state deltas the frontend cannot process back to the backend via a new client_error socket event, logging an actionable error in the terminal instead of failing silently. A frontend/backend state mismatch is fatal for the session: further events stop until the page is reloaded after the frontend is rebuilt or api_url is corrected. (#6827)
  • Framework logging now flows through standard python logging with per-module loggers (reflex_base.utils.log, re-exported as reflex.utils.log), bootstrapped on import reflex. Rich colored output is preserved, and REFLEX_LOG_JSON emits machine-readable JSON-lines records. --loglevel critical no longer prints the system-info banner. (#6863)
  • The reflex CLI accepts --json (equivalent to REFLEX_LOG_JSON) to emit machine-readable JSON-lines logs. (#6865)
  • reflex deploy accepts --min-instances and --max-instances to set the autoscaling bounds of an app deployed to Google Cloud. Omitted bounds are left unchanged. (#6884)
  • reflex deploy gains --gcp-connection, to pick which of your organization's connected GCP accounts an app deploys through; --full-deploy, to serve the frontend from the provider's own container instead of Reflex's CDN; and --strategy, which was previously only settable in the config file. (#6908)
  • Compiled components are now named for React DevTools: memoized components take a displayName from the Python class or @rx.memo function they came from instead of showing as Anonymous, generated contexts are named (StateContext(reflex___state____state.my_state).Provider rather than an unlabelled Context.Provider), pages are labelled with their route (Component(blog/[slug])), and client-only (NoSSRComponent) wrappers render as ClientSide(<Tag>). (#6945)

Bug Fixes

  • Stale on_load work no longer blocks or outlives a page navigation: a newer navigation for the same client now cancels the previous page's unfinished on_load event chain, including on_load handlers that are background tasks (@rx.event(background=True)), which 0.9.8 let run to completion. Background tasks started from other events are unaffected. (#6593)
  • A [[...splat]] catchall route no longer matches paths that merely share its prefix — posts/[[...splat]] matched /postsomething as well as /posts and its descendants, so the wrong page's on_load events could fire. (#6790)
  • Ensure state manager instances use isolated internal locks instead of sharing one lock across instances. (#6830)
  • Qualify dict annotations on BaseState that were shadowed by BaseState.dict, so type checkers resolve them to the builtin. (#6846)
  • reflex run now pre-enables the development export condition for the dev server via NODE_OPTIONS/BUN_OPTIONS, fixing the dev server exiting with restartWithMergedOptions() was called, but the process has already been restarted on installs without node, where react-router 8's CLI re-executes itself to set the condition. (#6857)
  • An AppHarnessProd no longer leaks REFLEX_ENV_MODE=prod to dev AppHarness instances created later in the same process, which made them compile with route prerendering enabled and drop events dispatched during hydration recovery. (#6857)
  • Cache event handler annotations before runtime state-class patches can shadow builtin names on Python 3.14. (#6890)
  • rx.script head updates now flush synchronously instead of via react-helmet's requestAnimationFrame batching, fixing intermittently missing script tags after hydration (flaky "scripts not loaded" failures). (#6905)
  • Fixed a race where a finishing background task could silently discard state updates made by a concurrently running event handler before they reached the frontend, leaving the UI stale until the next write. Background handlers that never enter async with self still emit their delta, now computed under the state lock. (#6920)
  • AppHarness starts the frontend dev server with the development export condition enabled, fixing "Frontend did not start" on node-less (bun-only) installs where react-router's dev CLI restart guard trips. (#6931)
  • Adding a page no longer raises a spurious RouteValueError when a static segment lines up with another route's dynamic segment (e.g. /posts/all/[x] alongside /posts/[id]). React Router resolves such siblings in favor of the static one, so only two differently named dynamic segments at the same position conflict. The check was also order-dependent: it only tripped when the bracket-carrying route was added second. (#6953)
  • Reduce published wheel and sdist size by removing misplaced generated artifacts. (#6966)
  • A client_error socket emit with no payload no longer raises an unhandled TypeError inside python-socketio's dispatch, which let any connected socket — even one without a valid token — spam asyncio tracebacks into the backend logs past the handler's rate limits. (#6984)
  • Console warnings and errors no longer print literal backslash-escaped brackets (e.g. dict\[str, str]). The rich-markup escapes were left over from the legacy console helpers, but the logging pipeline renders messages with markup disabled, so bracketed type names now print verbatim. VarAttributeError messages drop the same escapes. (#6989)
  • reflex run no longer hangs forever when a fatal error (e.g. the node minimum-version check on the npm path) exits the frontend worker thread while the backend blocks the main thread; the failure now interrupts the main thread and the CLI exits promptly with the original error. (#6990, #6994)

Performance

  • Remove the per-update asyncio.create_task wrapper in EventNamespace.emit_update, cutting scheduling overhead roughly in half for every outgoing state update. (#6734)
  • Dev mode no longer pays for React's per-element owner-stack capture: navigation clicks in a large app dropped from ~350ms to ~83ms of main-thread CPU (5.6x prod down to ~1.3x). In exchange React.captureOwnerStack() returns no owner frames in dev, which affects React DevTools' owner-stack view and custom error overlays built on that API; set REFLEX_REACT_OWNER_STACKS=1 to restore them. (#6905)
  • @rx.memo components with props bound to state are now auto-memoized at the call site: the state hooks those props need compile into a generated wrapper component instead of the page module. A state change re-renders that wrapper rather than the whole page, and React's memo stops there unless one of the prop values actually changed. (#6949)
  • The generated vite.config.js now declares a hook filter on the plugin that redirects react-dom/server to react-dom/server.node, so the bundler no longer calls into it for every import in the module graph — on the Reflex docs site that was ~15,800 calls per build to rewrite a single specifier. (#6959)

Documentation

  • Documented the provider, gcp_connection and full_deploy cloud config settings, including which settings a Google Cloud target ignores and why full_deploy is left unset rather than false by default. (#6908)

Miscellaneous

  • The generated package.json no longer carries a framework-owned postcss override; the pinned postcss dev dependency already forces a single resolved copy for every transitive requirer. Projects that already installed 0.9.8 keep an inert "postcss": "8.5.23" override in reflex.lock/package.json; it matches the dev-dependency pin, so it changes nothing today and can be deleted by hand. (#6854)
  • Upgrade the locked dev tooling: ruff 0.15.12 -> 0.16.2, pyright 1.1.408 -> 1.1.411, typer 0.25.1 -> 0.27.1. (#6893)
  • The reflex deploy command implementation moved out of the reflex package into reflex-hosting-cli, so cloud code is no longer shipped inside the framework. Flags and behavior are unchanged, and reflex-hosting-cli remains a dependency of reflex, so reflex deploy and reflex cloud stay available out of the box. If the package is not installed, these commands now report which package to install instead of failing with a missing-command error. (#6924)

v0.9.8.post1 (2026-08-18)

Features

  • reflex deploy accepts --min-instances and --max-instances to set the autoscaling bounds of an app deployed to Google Cloud. Omitted bounds are left unchanged. (#6884)
  • reflex deploy gains --gcp-connection, to pick which of your organization's connected GCP accounts an app deploys through; --full-deploy, to serve the frontend from the provider's own container instead of Reflex's CDN; and --strategy, which was previously only settable in the config file. (#6908)

Documentation

  • Documented the provider, gcp_connection and full_deploy cloud config settings, including which settings a Google Cloud target ignores and why full_deploy is left unset rather than false by default. (#6908)

v0.9.8 (2026-08-04)

Features

  • Added content-hash cache busting to rx.asset URLs. (#6550)
  • Add a preview run mode (reflex run --env preview) that hot reloads like dev but serves a freshly built, un-minified frontend bundle mounted into the backend instead of running the Vite dev server. Minification, CSS minification, autoprefixer, and sourcemaps are disabled by default for faster rebuilds and readable output (each overridable via VITE_MINIFY, REFLEX_NO_AUTOPREFIXER, and VITE_SOURCEMAP). (#6663)
  • Support using mutable state proxies as async context managers. (#6689)
  • Run plugins' staged register_route hooks once per app before page evaluation so plugins can contribute pages atomically, and invalidate the cached route resolver when a page is added after it was first built. (#6728)
  • reflex deploy now accepts --provider (deploy to Reflex Cloud or a GCP account connected to your organization) and --description (record an optional changelog note on the deployment, shown in reflex cloud apps history).

Bug Fixes

  • Fix reflex component build crashing with AttributeError on Python 3.10 and 3.11 by delegating recursive stub generation to the Python 3.10-compatible PyiGenerator scanner. (#6760)
  • Fixed reflex rename corrupting or failing on source files on non-UTF-8 platform locales while preserving declared Python source encodings and line endings. (#6761)
  • Fixed nested/subfolder stylesheets failing to load on Windows because the generated CSS @import used backslash path separators (which CSS treats as escape sequences); the import URL is now always POSIX-normalized. (#6762)
  • Process persisted package.json files before mirroring them into the web directory. (#6765)
  • Fix production frontend hydration on Windows when the system MIME registry maps JavaScript files to text/plain. (#6831)
  • Fixed reflex run failing with error: lockfile had changes, but lockfile is frozen after upgrading to a Reflex version that adds a package.json override. Overrides are now applied after the lockfile saved in reflex.lock/ has been installed, so it is no longer treated as out of date. (#6844)

Miscellaneous

  • Update dev pin Pillow==12.3.0 to avoid various CVE reports (#6836)
  • Update locked aiohttp==3.14.3 and cryptography==50.0.0, clearing CVE-2026-59881, CVE-2026-69243, CVE-2026-69244 and CVE-2026-69247. Both are transitive development dependencies of the docs app and are not installed with Reflex. (#6837)

v0.9.7 (2026-07-15)

Features

  • Added default_color_mode to rx.Config ("system", "light", or "dark", also settable via REFLEX_DEFAULT_COLOR_MODE), so apps can set the initial color mode — and use the built-in color mode switcher and rx.color_mode_cond — without pulling in the large Radix themes CSS. The value drives both the compiled ThemeProvider default and the pre-hydration preload script, so there is no flash of the wrong theme on first paint. An explicit rx.theme(appearance=...) still takes precedence. (#6716)
  • @rx.memo components now compile with a configurable JS wrapper: React's memo remains the default, wrapper= swaps in a custom function Var whose imports ride along into the generated module, and wrapper=None emits the bare function component. (#6730)
  • The new frozen_lockfile config option is now honored during frontend package installation: when enabled (the default), bun's initial install runs with --frozen-lockfile so a lockfile out of sync with package.json fails fast. Set frozen_lockfile=False to let the lockfile update in place instead. npm has no equivalent install flag today, so the option is a no-op there. (#6763)

Bug Fixes

  • Fix stateful pages being evaluated twice in one process (forked prod workers and same-process export+serve), which created duplicate ComponentState classes and broke frontend hydration (TypeError: d is not a function). (#6710)
  • Reset the disk state manager write queue task after close. (#6715)
  • Close the RedisTokenManager redis client and cancel its pub/sub background tasks on app shutdown, fixing leaked redis connections (ResourceWarning: unclosed Connection) when the server stops. (#6724)
  • Event handlers and computed vars inherited from a state mixin now preserve the source function's custom attributes and keyword-only defaults. (#6725)

Performance

  • Run anonymous telemetry collection and delivery on a dedicated single-worker background thread instead of inline on the asyncio event loop. The blocking syscalls, subprocess calls and synchronous HTTP request used to gather and post an event no longer stall the event loop — notably when reporting backend errors at a high rate. Delivery is best-effort and any failure is suppressed, so telemetry can never affect the running app. (#6626)
  • Event chaining (yield OtherState.handler(rows)) no longer deep-copies payload values that are not attached to any state: only state-bound MutableProxy subtrees are copied, making proxy-free payloads ~5x faster to chain. (#6739)
  • Var.to() and Var.guess_type() resolve their target Var subclass through cached registry lookups instead of scanning the full registry with safe_issubclass on every call. (#6742)

v0.9.6 (2026-06-25)

Features

  • Auto-memoized (rx.memo) components now compile to .web/app_components/ output paths that mirror their defining Python source module (using the real package name, including framework packages) instead of being bundled into a single shared components.jsx. The compiler's auto-memo registry is scoped per source module, so identical-rendering subtrees in different modules each emit their own output instead of one silently overwriting another, hot-reloads of a module refresh the correct output, and stale memo files are cleaned up when their source changes. Memos whose module can't be mirrored (__main__, unsafe names) fall back to one file per memo at .web/utils/components/<name>.jsx. Each mirrored memo's generated export name also carries a stable per-module suffix, so two memos that share a name in different modules compile to distinct symbols and can be used together on one page without colliding. (#6457)
  • rx._x.hybrid_property now works on dataclasses, pydantic models and SQLAlchemy models, not just State classes. Accessing the property through an object var on the frontend (e.g. State.info.a_b) renders it as a var, using the same code you already use on the backend. (#6617)
  • reflex init now writes a Reflex-managed section into AGENTS.md (fetched from the canonical source and delimited by markers that preserve surrounding user content), and bridges it for Claude Code by creating a CLAUDE.md importing @AGENTS.md — or, if a CLAUDE.md exists without the import, managing the section there directly. (#6620)
  • rx._x.hybrid_property now raises a clear error when its frontend logic reads a backend (underscore-prefixed) state var, instead of silently baking the var's server-side default into the frontend. Reference a regular var, or provide a separate frontend implementation with @<name>.var. (#6621)

Bug Fixes

  • Sync reflex.lock/package.json to .web/package.json before installing packages to ensure lock file and package.json are aligned. (#6658)
  • Avoid re-entering config loading when a State subclass is defined in rxconfig.py. (#6662)
  • Raise minimum dependency versions to pull in security fixes: starlette>=1.3.1 (Host-header path poisoning, request.form() DoS, and UNC-path SSRF), python-multipart>=0.0.32 (quadratic-time querystring DoS, unbounded header field size, and negative Content-Length buffering in parse_form), and granian>=2.7.4 (WSGI and WebSocket header-panic DoS). (#6665)
  • Fixed modify_state to rebind EventContext.token to the token being modified, so delta resolution and computed vars inside shared-state fan-out tasks observe the correct client token rather than the triggering event's inherited context. (#6673)

v0.9.5.post2 (2026-06-10)

Bug Fixes

  • Allow access to State from app_wrap components (#6651)

v0.9.5.post1 (2026-06-10)

Bug Fixes

  • Bumped minimum reflex-components-core dependency to 0.9.5 for compatibility.

v0.9.5 (2026-06-10)

Features

  • rx.form on_submit handlers can now annotate their form-data parameter with a TypedDict (including typing_extensions.NotRequired fields). The submitted mapping is accepted by the event-argument type checker, and at component build time the form statically validates that its controls supply every required TypedDict field, raising EventHandlerValueError — with the missing and present field names — when a required field has no control with a matching static name/id. Validation is skipped when the form sets an id (controls may be associated externally via the HTML form attribute) or when any control identifier is a dynamic Var. (#6301)
  • Event handlers attached to JSX literals built outside a component's render scope — such as an ErrorBoundary's onError — can now dispatch events. addEvents is reached through a module-level import that EventLoopProvider populates on each render, so dispatch no longer depends on a useContext hook being hoisted into the calling scope. The state and event-loop providers, previously hard-coded in the layout template, are now injected around the app root by the compiler from the app_wraps declared on the Vars that use them. (#6447)
  • Added App.hydrate_fallback, a component rendered during the page's hydration window (React Router's HydrateFallback) instead of a blank white page. It can also be configured without code through the hydrate_fallback config — a dotted import path to a no-arg callable returning a component, settable via the REFLEX_HYDRATE_FALLBACK environment variable — with the App argument taking precedence. Note that the fallback only covers the hydration window after the JS bundle has loaded, not the initial bundle download. (#6630)
  • Added the REFLEX_HOT_RELOAD_OVERRIDE_PATHS environment variable, a colon-separated list of paths that, when set, fully replaces the paths watched for hot reload in dev mode — taking precedence over the config-derived defaults as well as REFLEX_HOT_RELOAD_INCLUDE_PATHS and REFLEX_HOT_RELOAD_EXCLUDE_PATHS. (#6639)

Bug Fixes

  • Anonymous telemetry now reports the installation and project identifiers as UUID strings rather than 128-bit integers. PostHog coerced the large integers to floats, discarding all but ~16 significant digits and risking distinct installs or apps being correlated as one. Each identifier is re-encoded to the same value (a UUID carries the same 128 bits), and a one-time PostHog $create_alias links an installation's pre-existing history to its new identifier so continuity is preserved. (#6611)
  • scripts/make_pyi.py is now a proper CLI for maintaining pyi_hashes.json: --force regenerates every default target (ignoring the incremental markers), explicit targets are merged into the registry instead of pruning it, and an unreachable last-run commit (after a branch switch or rebase) triggers a full regeneration. A new --check mode, wired into the pre-commit CI job, fails when a pyi_hashes.json entry no longer has a matching .py source. (#6614)
  • State.get_var_value() no longer silently returns a wrong value when passed a Var operation — an arithmetic/concatenation expression such as State.a + State.b, or an indexed/item access such as State.items[0]. Previously it resolved the state and field of the operation's first operand and returned that field's value instead of the operation's result. It now raises UnretrievableVarValueError, consistent with how it already handled vars not associated with any state. Plain field and computed-var references continue to resolve as before. (#6633)

Performance

  • Speed up reading mutable state vars (lists, dicts, dataclasses) through MutableProxy. The per-element check that detects dataclasses.asdict/astuple recursion now reads frame.f_code.co_filename directly instead of calling inspect.getfile(), cutting proxy read overhead by roughly 3-4x on large containers without changing behavior. (#6600)

Miscellaneous

  • Report the versions of the first-party Reflex subpackages shipped with Reflex (reflex-base, the reflex-components-* family and reflex-hosting-cli) in anonymous telemetry via a new reflex_package_version field. The set is derived from Reflex's own declared dependencies, so unrelated third-party reflex-* packages are never reported. Now that Reflex is split across many independently-versioned packages, the single reflex_version field no longer reflects the full install. (#6610)

v0.9.4 (2026-06-03)

Deprecations

  • rx._x.memo is deprecated in favor of rx.memo. The old name remains a working alias for now; update imports to use rx.memo directly. (#6517)
  • @rx.memo now expects each parameter to be annotated as rx.Var[...] (or rx.RestProp/rx.EventHandler) and the function to declare an rx.Component or rx.Var[...] return type. Memos that still use bare Python types (e.g. name: str) or omit the return annotation keep working — the values are coerced to rx.Var[...]/rx.Component and a deprecation warning points at the parameters and return type that need explicit annotations — but this fallback will be removed in 1.0. (#6598)

Features

  • Added rx._x.hybrid_property, a property decorator usable on State classes that works like a normal Python property for backend access while also rendering on the frontend at class level. Use the same method for both, or register a separate frontend implementation with @<name>.var. (#3806)
  • Promoted the component memo system to a first-class rx.memo API. Memo-decorated components now accept rx.EventHandler parameters and carry annotated return types so they type-check correctly at call sites. (#6517)
  • Added rx.EMPTY_VAR_COMPONENT, an empty-component rx.Var[rx.Component] sentinel for use as a default on @rx.memo children slots (and any rx.Var[rx.Component] prop) — the component counterpart to rx.EMPTY_VAR_STR and rx.EMPTY_VAR_INT. (#6598)
  • @rx.memo now evaluates the decorated function body lazily — on first use (component instantiation) or at compile time — instead of at import time. This speeds up startup and lets a memo reference modules that aren't fully imported yet, sidestepping circular-import errors during decoration. Body-dependent errors (e.g. a var-returning memo that uses hooks or non-bundled imports) now surface when the memo is first used or compiled rather than at import. (#6598)

Miscellaneous

  • Introduced towncrier-based changelog management. Each PR that changes package source now adds a fragment under the affected package's news/ directory; fragments are assembled into CHANGELOG.md at release time. See CONTRIBUTING.md for the full workflow. (#6350)
  • Removed the "choose templates" option from reflex init. The interactive prompt now offers only a blank app or the AI builder, and no longer opens the open-source templates page. (#6592)