## 1. Project Overview & Quickstart (Unleash/unleash) ## File: README.md ## What is Unleash? Unleash is a powerful open-source solution for feature management. It streamlines your development workflow, accelerates software delivery, and empowers teams to control how and when they roll out new features to end users. With Unleash, you can deploy code to production in smaller, more manageable releases at your own pace. Feature flags in Unleash let you test your code with real production data, reducing the risk of negatively impacting your users' experience. It also enables your team to work on multiple features simultaneously without the need for separate feature branches. Unleash is the most popular open-source solution for feature flagging on GitHub. It supports 15 official client and server SDKs and over 15 community SDKs. You can even create your own SDK if you wish. Unleash is compatible with any language and framework. ## Get started with Unleash ### Set up Unleash To get started with Unleash, you can either explore [Unleash Enterprise](#unleash-enterprise) with a free trial or [get started locally](#unleash-open-source) with our open-source solution. #### Unleash Enterprise To start with Unleash Enterprise, [request a free trial](https://www.getunleash.io/plans/enterprise-payg?utm_source=oss&utm_medium=readme&utm_content=unleash-enterprise-start). This gives you access to a hosted instance with unlimited projects and environments and features such as [role-based access control](https://docs.getunleash.io/concepts/rbac), [change requests](https://docs.getunleash.io/concepts/change-requests), [single sign-on](https://docs.getunleash.io/concepts/sso), and [SCIM](https://docs.getunleash.io/concepts/scim) for automatic user provisioning. #### Unleash Open Source To set up Unleash locally, you'll need [`git`](https://git-scm.com/) and [`docker`](https://www.docker.com/) installed on your machine. Execute the following commands: ```bash git clone git@github.com:Unleash/unleash.git cd unleash docker compose up -d ``` Then point your browser to `localhost:4242` and log in using: - username: `admin` - password: `unleash4all` If you'd rather run the source code in this repo directly via Node.js, see the [step-by-step instructions to get up and running in the contributing guide](./contributing/CONTRIBUTING.md#how-to-run-the-project). ### Connect your SDK Find your preferred SDK in [our list of official SDKs](#unleash-sdks) and import it into your project. Follow the setup guides for your specific SDK. If you use the docker compose file from the previous step, here's the configuration details you'll need to get going: - For frontend SDKs, use: - URL: `http://localhost:4242/api/frontend/` - `clientKey`: `default:development.unleash-insecure-frontend-api-token` - For backend SDKs, use: - Unleash API URL: `http://localhost:4242/api/` - API token: `default:development.unleash-insecure-api-token` If you use a different setup, your configuration details will most likely also be different. ### Check a feature flag Checking the state of a feature flag in your code is easy! The syntax will vary depending on your language, but all you need is a simple function call to check whether a flag is available. Here's how it might look in Java: ```java if (unleash.isEnabled("AwesomeFeature")) { // do new, flashy thing } else { // do old, boring stuff } ``` ## Try Unleash in the cloud Want to explore Unleash without setting it up locally? Here are two easy ways to see it in action. ### Live demo Open a running Unleash environment in your browser with no signup or setup required. This shared demo instance includes the core functionality so you can quickly get a feel for how Unleash works. **→ [Launch the live demo](https://www.getunleash.io/interactive-demo?utm_source=readme&utm_medium=oss&utm_content=demo-section-cta)** [](https://www.getunleash.io/interactive-demo?utm_source=readme&utm_medium=oss&utm_content=demo-section-cta) ### Free Enterprise trial Get your own dedicated instance with a free 14-day cloud trial. This includes the full Unleash Enterprise feature set; ideal when evaluating Unleash for production use. **→ [Start your free trial](https://www.getunleash.io/plans/enterprise-payg?utm_source=readme&utm_medium=oss&utm_content=demo-section-cta)** ## Deploying to a production server To self-host Unleash in a production environment, you need to deploy it to a persistent server. We provide guides for deploying to services like Heroku and DigitalOcean: [](https://www.heroku.com/deploy/?template=https://github.com/Unleash/unleash) [](https://cloud.digitalocean.com/apps/new?repo=https://github.com/Unleash/unleash/tree/main&refcode=0e1d75187044) For more advanced configurations options, check out our documentation on: - [Getting started with self-hosting](https://docs.getunleash.io/deploy/getting-started) - [Unleash configuration options](https://docs.getunleash.io/deploy/configuring-unleash) ## Community and help We know that learning a new tool can be hard and time-consuming. We have a growing community that loves to help out. Please don't hesitate to reach out for help. [](https://slack.unleash.run) 💬 [Join Unleash on Slack](https://slack.unleash.run) if you want ask open questions about Unleash, feature toggling or discuss these topics in general. 💻 [Create a GitHub issue](https://github.com/Unleash/unleash/issues/new) if you have found a bug or have ideas on how to improve Unleash. 📚 [Visit the documentation](https://docs.getunleash.io/) for more in-depth descriptions, how-to guides, and more. 📖 Learn more about the principles of building and scaling [feature flag](https://docs.getunleash.io/guides/feature-flag-best-practices) solutions. ## Contribute to Unleash Unleash is the largest [open-source feature flag solution](https://www.getunleash.io/) on GitHub. Building Unleash is a collaborative effort, and we owe a lot of gratitude to many smart and talented individuals. Building it together with the community ensures that we build a product that solves real problems for real people. We'd love to have your help too: Please feel free to open issues or provide pull requests. Check out [the CONTRIBUTING.md file](./contributing/CONTRIBUTING.md) for contribution guidelines and the [Unleash developer guide](https://docs.getunleash.io/contribute) for tips on environment setup, running the tests, and running Unleash from source. Before a pull request can be merged, contributors must read and agree to the [Unleash Contributor License Agreement](./CLA.md). ### Contributors ## Documentation You can visit the Unleash documentation at https://docs.getunleash.io. As of 2 February 2026, the Unleash documentation source code lives in its own repository: [Unleash/unleash-documentation](https://github.com/Unleash/unleash-documentation). ## Features our users love ### Flexibility and adaptability - Get an overview of all feature flags across all your environments, applications and services - Targeted releases using [activation strategies](https://docs.getunleash.io/concepts/activation-strategies) to enable and disable features for certain users or segments without having to redeploy your application. - [Canary releases / gradual rollouts](https://docs.getunleash.io/concepts/activation-strategies) - [Kill switches](https://docs.getunleash.io/concepts/feature-flags#feature-flag-types) - [A/B testing](https://docs.getunleash.io/guides/a-b-testing) - 2 [environments](https://docs.getunleash.io/concepts/environments) - Organize feature flags using [tags](https://docs.getunleash.io/concepts/feature-flags#tags) - Out-of-the-box integrations with popular tools ([Slack](https://docs.getunleash.io/integrate/slack-app), [Microsoft Teams](https://docs.getunleash.io/integrate/teams), [Datadog](https://docs.getunleash.io/integrate/datadog)) + integrate with anything with [webhooks](https://docs.getunleash.io/integrate/webhook) - [Insights for managing technical debt](https://docs.getunleash.io/concepts/technical-debt) and [stale flags](https://docs.getunleash.io/concepts/technical-debt#stale-and-potentially-stale-flags) - API-first: _everything_ can be automated. No exceptions. - [12 official SDKs](https://docs.getunleash.io/sdks#official-sdks), and 10 [community-contributed SDKs](https://docs.getunleash.io/sdks#community-sdks) - Run it via Docker with the [official Docker image](https://hub.docker.com/r/unleashorg/unleash-server) or as a pure Node.js application ### Security and performance - Privacy by design (GDPR and Schrems II). End-user data never leaves your application. - [Audit logs](https://docs.getunleash.io/concepts/events) - Enforce [OWASP's secure headers](https://owasp.org/www-project-secure-headers/) via the strict HTTPS-only mode - Flexible hosting options: host it on premise or in the cloud (_any_ cloud) - Scale with [Unleash Edge](https://docs.getunleash.io/unleash-edge) independently of the Unleash server to support any number of frontend clients without overloading your Unleash instance ### Looking for more features? If you're looking for one of the following features, please take a look at our [Pro and Enterprise plans](https://www.getunleash.io/plans): - [role-based access control (RBAC)](https://docs.getunleash.io/concepts/rbac) - [single sign-on (SSO)](https://docs.getunleash.io/concepts/sso) - more environments - [feature flags project support](https://docs.getunleash.io/concepts/projects) - [advanced segmentation](https://docs.getunleash.io/concepts/segments) - [additional strategy constraints](https://docs.getunleash.io/concepts/activation-strategies#constraints) - tighter security - more hosting options (we can even host it for you!) ## Architecture Read more in the [_system overview_ section of the Unleash documentation](https://docs.getunleash.io/get-started/unleash-overview#system-overview). ## Unleash SDKs To connect your application to Unleash you'll need to use a client SDK for your programming language. **Official backend SDKs:** - [Go SDK](https://docs.getunleash.io/sdks/go) - [Java SDK](https://docs.getunleash.io/sdks/java) - [Node.js SDK](https://docs.getunleash.io/sdks/node) - [PHP SDK](https://docs.getunleash.io/sdks/php) - [Python SDK](https://docs.getunleash.io/sdks/python) - [Ruby SDK](https://docs.getunleash.io/sdks/ruby) - [Rust SDK](https://github.com/unleash/unleash-client-rust) - [.NET SDK](https://docs.getunleash.io/sdks/dotnet) **Official frontend SDKs:** - [Android SDK](https://docs.getunleash.io/sdks/android) - [Flutter SDK](https://docs.getunleash.io/sdks/flutter) - [iOS SDK](https://docs.getunleash.io/sdks/ios) - [JavaScript SDK](https://docs.getunleash.io/sdks/javascript-browser) - [React SDK](https://docs.getunleash.io/sdks/react) - [Svelte SDK](https://docs.getunleash.io/sdks/svelte) - [Vue SDK](https://docs.getunleash.io/sdks/vue) **Community SDKs:** If none of the official SDKs fit your need, there's also a number of [community-developed SDKs](https://docs.getunleash.io/sdks#community-sdks) where you might find an implementation for your preferred language (such as [Elixir](https://gitlab.com/afontaine/unleash_ex), [Dart](https://pub.dev/packages/unleash), [Clojure](https://github.com/AppsFlyer/unleash-client-clojure), and more). ## Users of Unleash **Unleash is trusted by thousands of companies all over the world**. **Proud Open-Source users:** (send us a message if you want to add your logo here) ## Migration guides Unleash has evolved significantly over the past few years, and we know how hard it can be to keep software up to date. If you're using the current major version, upgrading shouldn't be an issue. If you're on a previous major version, check out the [Unleash migration guide](https://docs.getunleash.io/deploy/upgrading-unleash)! ## Want to know more about Unleash? ### Videos and podcasts - [The Unleash YouTube channel](https://www.youtube.com/channel/UCJjGVOc5QBbEje-r7nZEa4A) - [_Feature toggles — Why and how to add to your software_ — freeCodeCamp (YouTube)](https://www.youtube.com/watch?v=-yHZ9uLVSp4&t=0s) - [_Feature flags with Unleash_ — The Code Kitchen (podcast)](https://share.fireside.fm/episode/zD-4e4KI+Pr379KBv) - [_Feature Flags og Unleash med Fredrik Oseberg_ — Utviklerpodden (podcast; Norwegian)](https://pod.space/utviklerpodden/feature-flags-og-unleash-med-fredrik-oseberg) ### Articles and more - [The Unleash Blog](https://www.getunleash.io/blog) - [_Designing the Rust Unleash API client_ — Medium](https://medium.com/cognite/designing-the-rust-unleash-api-client-6809c95aa568) - [_FeatureToggle_ by Martin Fowler](http://martinfowler.com/bliki/FeatureToggle.html) - [_Feature toggling transient errors in load tests_ — nrkbeta](https://nrkbeta.no/2021/08/23/feature-toggling-transient-errors-in-load-tests/) - [_An Interview with Ivar of Unleash_ — Console](https://console.substack.com/p/console-42) - [_Unleash your features gradually_](http://ivarconr.github.io/feature-toggles-presentation/sch-dev-lunch-2017/#1 ' '), slideshow/presentation by Ivar, the creator of Unleash --- ## File: frontend/cypress/README.md ## Unleash Behavioural tests ### Add common commands to Cypress - `global.d.ts` is where we extend Cypress types - `API.ts` contains api requests for common actions (great place for cleanup actions) - `UI.ts` contains common functions for UI operations - `commands.ts` is the place to map the functions to a cypress command ### Test Format Ideally each test should manage its own data. Avoid using `after` and `afterEach` hooks for cleaning up. According to Cypress docs, there is no guarantee that the functions will run Suggested Format: - `prepare` - `when` - `then` - `clean` #### Passing (returned) parameters around ```ts it('can add, update and delete a gradual rollout strategy to the development environment', async () => { cy.addFlexibleRolloutStrategyToFeatureUI({ featureToggleName, }).then(value => { strategyId = value; cy.updateFlexibleRolloutStrategyUI(featureToggleName, strategyId).then( () => cy.deleteFeatureStrategyUI(featureToggleName, strategyId) ); }); }); ``` --- ## File: frontend/src/component/impact-views/README.md # Impact Views (experimental) Impact views let a user follow a set of feature flags and their impact metrics together on a single chart. The **full** feature (built on the `feat/exp-views` branch) includes goal-tracking and system-health templates, a "top flag movers" panel, a flag-impact dialog, and a view editor. We are re-introducing it onto `main` incrementally. **The current, narrowed scope is a basic goal-tracking view with dummy data** — see "Rollout plan" for what is in scope now vs. deferred. This feature is **experimental and intentionally not production-hardened**: - **Storage is browser `localStorage`** — there is no backend persistence, no new database tables, and no new API endpoints. The getters used here hit existing endpoints only (e.g. `api/admin/search/events`). - It is **gated behind the `impactViews` feature flag** and served from the self-contained `/impact-views` route. - Everything is **co-located under this directory** so the feature can be removed cleanly (see "Deletion contract" below). ## Layout ``` component/impact-views/ ImpactViewsPage.tsx # page: switcher + active view's chart (useGoalViewData) LazyImpactViewsPage.tsx # lazy wrapper used by the route views/ # components (GoalSummaryPanel, MultimetricChartCard, FollowedFeaturesList, # ViewSwitcher, FeaturePicker, ViewEditorDialog, ImpactMetricViewsEmptyState, …) hooks/ # data hooks (useGoalViewData seam + resolver/event/metrics hooks) # + useImpactMetricViews (localStorage CRUD) ``` **Reused from `main` (imported, not copied):** the `MultimetricChart` suite (`chartConfig`, `types`, `FeatureEventOverlay/eventTheme`, `MultimetricTotals`), `metricsFormatters`, `useFeatureEnvironmentEvents`, `useImpactMetricsMetadata` (`useImpactMetricsOptions`), `useEnvironments`, `useFeatureSearch`, `useLocalStorageState`, `createUuid`, `PageHeader`, `PageContent`, `LineChart`, `FeatureLifecycleStageIcon`. ## Rollout plan (small, independently-mergeable PRs) Source of the view files: the `feat/exp-views` branch under `frontend/src/component/impact-metrics/views/`. Extract file contents (not commits — the branch carries unrelated churn) and adjust import paths to the co-located locations. **Current focus: the view editor + localStorage CRUD** — let users create/edit/switch/delete their own views, persisted in browser localStorage. The basic goal-tracking view already renders **real** sandbox data. See "Status" and the "NEXT" section below for exactly where to resume. Scope is **goal-tracking only**. Still **deferred** (revisit later): the system-health view, the **Top Movers** panel and the **Flag Impact** dialog (and the flag-event impact math behind them), and the synthetic-data generators. | PR | Contents | |----|----------| | **1** ✅ | `impactViews` flag (backend `experimental.ts` + frontend `UiFlags`), `/impact-views` route, gated nav item, stub page + this README. | | **2** | Goal-view types + goal summary (no components, no API calls): `views/types.ts`, `computeGoalSummary(+test)`. | | **3** | Goal summary panel (render-only): `GoalSummaryPanel`. (`FollowedFeaturesStrip` dropped — dead code, nothing imports it.) | | **4** | Chart card (render-only layout): `views/MultimetricChartCard/MultimetricChartCard.tsx`. (Getter `useGroupedImpactMetricsData` deferred to the real-data PR — not needed for dummy data.) | | **5** | Followed-features list (render-only): `views/FollowedFeaturesList/FollowedFeaturesList.tsx`, rendered below the card on the page with dummy feature names. (The `GoalTrackingViewChart` orchestrator and `useMergedFeatureEvents` stay with the deferred real-data wiring — they exist to fetch live data the dummy view doesn't need.) | | **(later)** | Replace the per-piece dummy wiring on `ImpactViewsPage` with a single cohesive dummy goal view / `GoalTrackingViewChart` if desired — optional polish, no new components. | | **Deferred** | **Top Movers / Flag Impact** (`computeFlagEventImpact`, `flagImpactFormatting`, `TopFlagMoversPanel`, `FlagImpactDialog`); real-data wiring; view editor + localStorage CRUD (`ViewEditorDialog`, `useImpactMetricViews`, `FeaturePicker`, `TemplatePickerDialog`, `ViewSwitcher`, `ImpactMetricViews`); system-health view (`SystemHealthViewChart`, `ViewChart` template router, `useAutoFollowedFeatureNames`, `useEnvironmentEvents`, `normalizeSeriesToBaseline`); the synthetic generator `simulateFlagContribution`. | ## Status - **PR 1** — merged (#12173). Flag, route, nav, stub page, this README. - **PR 2** — merged (#12177). `views/types.ts` + `views/computeGoalSummary.ts(+test)`. - **PR 3** — merged. `views/GoalSummaryPanel/` (panel + extracted, tested `sparkline.ts`). (Shipped with a throwaway dummy preview that was later replaced by real data in PR 6.) - **PR 4** — merged. `views/MultimetricChartCard/MultimetricChartCard.tsx` (render-only layout card, prop interface tightened to what the goal view needs). The page now renders the card with dummy data and the `GoalSummaryPanel` in its `totalsHeaderSlot`. **Note:** the branch version passed `highlightedEventId` / `eventImpactById` to `` and exported `FeatureEventImpactSummary` — those `MultimetricChart` props are **branch-only additions** (deferred Top Movers / event-tooltip work), NOT on `main`, so they were stripped from the co-located card. When Top Movers lands, re-add them to both `MultimetricChart` and this card. - **PR 5** — merged. `views/FollowedFeaturesList/FollowedFeaturesList.tsx` rendered below the chart card. Made **presentational**: it takes `features: ResolvedFeature[]` and only groups + renders them (data fetching deferred to the real-data phase). Trimmed (550 → ~310) and refactored into `StageBadge`/`GroupHeaderRow`/`FeatureRow`. Labels come from the shared `getFeatureLifecycleName`. `PageContent` wrapper removed from the page. - **PR 6** — merged. **Real data** from a hardcoded view template. The page is data-driven: `useGoalViewData(view)` fans out to live getters and feeds the card/panel/list. Pieces (all hooks under `hooks/`): - `fixtures/goalViewConfig.ts` — `GOAL_VIEW` (`purchases` goal + `error_rate`, `count`/ `month`; flags `impact-views-1/2/3`). **Project-agnostic** — a view holds only `featureNames`; each flag's project is resolved from the flag itself (no `project` on `MetricView`). `id`/`createdAt`/`updatedAt` stay required (`GOAL_VIEW` stubs them). *(This fixture was removed in PR C once localStorage-backed user views replaced the seed data.)* - `hooks/useGoalViewData.ts` (+`.test.tsx`) — composition seam (the only file the page calls). Picks the goal series/total by the **goal metric's index** (not `[0]`); handles empty series. - `hooks/useResolvedFeatures.ts` — `featureNames` → `ResolvedFeature[]` via **one cross-project** `useFeatureSearch({ query: names.join(',') })` (backend → `name ILIKE ANY`), filtered client-side by exact name. (feature-search `limit` capped at 100 server-side.) - `hooks/useFollowedFeatureEvents.ts` — all flags' toggle events in **one** cross-project request via the shared `useEventSearch` getter (`feature: IS_ANY_OF:…`), mapped for the chart overlay. No per-flag loaders. - Chart/totals/window from on-`main` `useGroupedImpactMetricsData(view.metrics)`; goal summary from `computeGoalSummary`. - **Architecture:** each data concern is its own small hook behind a narrow interface (all under `hooks/`); the page has no fetching logic. ### Editor + localStorage CRUD (goal-tracking only) — ✅ COMPLETE Users create/edit/switch/duplicate/delete their own views, persisted in browser localStorage. Extracted from `feat/exp-views:.../views/`, **stripping** template/system-health/`normalize`/ `autoFollowFlags`. 4 PRs, all merged: - **PR A** — View **switcher** (`views/ViewSwitcher/`). Page held `activeViewId` and rendered the active view via `useGoalViewData`. (Seeded from a temporary `DUMMY_VIEWS` fixture, since removed.) - **PR B1** — `views/FeaturePicker/FeaturePicker.tsx` — MUI ``, 250ms debounce. - **PR B2** — `views/ViewEditorDialog/ViewEditorDialog.tsx` (goal-only create/edit form, shared `Dialogue` chrome, single view-level aggregation via `GeneralSelect`, `useReducer` form state) + page wiring (in-memory create/edit via the `editor` discriminated union). - **PR C** — `hooks/useImpactMetricViews.ts` (localStorage CRUD: keys `impact-metric-views:list` / `impact-metric-views:active-id`, via `useLocalStorageState` + `createUuid`, real `Date.now()` timestamps) + `hooks/useImpactMetricViews.test.tsx` + `views/ImpactMetricViewsEmptyState/`. Page now uses the hook (no more in-memory state / `DUMMY_VIEWS`): empty storage → empty-state CTA; delete → shared `Dialogue` confirm; duplicate → `duplicateView`. The `goalViewConfig.ts` fixture was deleted (dead once localStorage landed). ## NEXT: deferred work (revisit when prioritized) The editor phase is done. Remaining deferred items (not yet started) — see the table above and "Decisions & context" below: - **Top Movers / Flag Impact** — `computeFlagEventImpact(+test)`, `flagImpactFormatting`, `TopFlagMoversPanel`, `FlagImpactDialog` (re-extract from `feat/exp-views`; not on `main`). - **System-health view** — `SystemHealthViewChart`, `ViewChart` template router, `useAutoFollowedFeatureNames`, `useEnvironmentEvents`, `normalizeSeriesToBaseline`. - Synthetic generator `simulateFlagContribution`. Extraction mechanic unchanged: `git show feat/exp-views:.../` → strip template/system-health/`normalize`/`autoFollowFlags` + comments → point imports at on-`main` modules. ## Decisions & context (for picking this up later) - **Real data is live** — the goal view renders real sandbox data (PR 6). All dummy fixtures (including the `DUMMY_VIEWS`/`GOAL_VIEW` `goalViewConfig.ts`) have been removed; views are now user-created and persisted in localStorage (PR C). - **No backend work** is needed; getters hit existing endpoints. If an extracted file imports a symbol not on `main`, add the smallest co-located copy rather than editing shared/backend code. - **`types.ts` is trimmed to goal-tracking-only** (`MetricView`, `ViewMetricConfig`). The template machinery (`ViewTemplate`/`TEMPLATE_DEFAULTS`/`DEFAULT_VIEW_*`), localStorage keys, and default env/timeRange constants were removed — they come back (re-extracted + stripped of system-health) with the editor/CRUD PRs. `MetricView` has **no `project`** (project-agnostic; resolved per-flag) and keeps `id`/`createdAt`/`updatedAt` required. - **Cross-project, one-request data fetching** — the resolver and event hooks deliberately avoid per-flag requests + per-project filters; they query all followed flags at once (`query: names.join(',')` / `feature: IS_ANY_OF:…`). Keep this pattern when extending. - **PR-2 history note:** PR 2 originally bundled the flag-impact math; it was split into a stacked "PR 2b" (#12178) which was then **closed** when Top Movers / Flag Impact was deferred. So `computeFlagEventImpact(+test)` and `flagImpactFormatting` are *not* yet on `main` — re-extract them from `feat/exp-views` when picking up Top Movers. - **Extraction mechanic:** `git show feat/exp-views:frontend/src/component/impact-metrics/views/` → write into `views/`, then point imports at the on-`main` shared modules (and at co-located `../hooks/` once PR 4 lands). Keep extracted files close to their branch originals to ease later wiring. ## Flag wiring - Backend: `impactViews` in `src/lib/types/experimental.ts` (env var `UNLEASH_EXPERIMENTAL_IMPACT_VIEWS`, default `false`). - Frontend: `impactViews` in `frontend/src/interfaces/uiConfig.ts` (`UiFlags`). - Route: `/impact-views` in `frontend/src/component/menu/routes.ts` (`flag: 'impactViews'`). - Nav: gated `PrimaryListItem` in `frontend/src/component/layout/MainLayout/NavigationSidebar/NavigationList.tsx`. ## Deletion contract Removing the feature is: delete this `component/impact-views/` directory, the one `/impact-views` entry in `routes.ts`, the gated nav line in `NavigationList.tsx`, and the two `impactViews` flag declarations (backend + frontend). --- ## File: frontend/README.md # frontend This directory contains the Unleash Admin UI frontend app. ## Run with a local instance of the unleash-api Refer to the [Contributing to Unleash](../CONTRIBUTING.md#how-to-run-the-project) guide for instructions. The frontend dev server runs (in port 3000) simultaneously with the backend dev server (in port 4242): ``` pnpm install pnpm dev ``` ## Run with a sandbox instance of the Unleash API Alternatively, instead of running unleash-api on localhost, you can use a remote instance: ``` cd ./frontend pnpm install pnpm run start:sandbox ``` ## Running end-to-end tests against localhost If you need to test against a local server instance, you'll need to run in the root directory: * `pnpm build:frontend` * `pnpm dev:start` Then run the e2e tests using: ``` pnpm run e2e ``` You may also need to test that a feature works against the enterprise version of unleash. ``` pnpm run start:enterprise pnpm run e2e:enterprise ``` ### Debugging end-to-end tests Run backend and frontend in development build. In the root of the project run e.g.: `pnpm dev`. Please keep in mind that running tests against dev frontend will be **really** slow (even x5 slower). It's best to open cypress UI and pick only the test that you need to work on. In frontend project run: ``` pnpm e2e:dev:open ``` ## Generating the OpenAPI client The frontend uses an OpenAPI client generated from the backend's OpenAPI spec. Whenever there are changes to the backend API, the client should be regenerated: For now we only use generated types (src/openapi/models). We will use methods (src/openapi/apis) for new features soon. ``` pnpm gen:api rm -rf src/openapi/apis ``` clean up `src/openapi/index.ts` imports, only keep first line `export * from './models';` This script assumes that you have a running instance of the enterprise backend at `http://localhost:4242`. The new OpenAPI client will be generated from the runtime schema of this instance. The target URL can be changed by setting the `UNLEASH_OPENAPI_URL` env var. ## Analyzing bundle size `npx vite-bundle-visualizer` in the root of the frontend directory ## 2. Official Technical Reference & Guides (Unleash/unleash-documentation) # Unleash Documentation ## What is Unleash? Unleash is a powerful open-source solution for feature management. It streamlines your development workflow, accelerates software delivery, and empowers teams to control how and when they roll out new features to end users. With Unleash, you can deploy code to production in smaller, more manageable releases at your own pace. Feature flags in Unleash let you test your code with real production data, reducing the risk of negatively impacting your users' experience. It also enables your team to work on multiple features simultaneously without the need for separate feature branches. Unleash is the most popular open-source solution for feature flagging on GitHub. It supports 15 official client and server SDKs and over 15 community SDKs. You can even create your own SDK if you wish. Unleash is compatible with any language and framework. **[Try Unleash Enterprise for free](https://www.getunleash.io/plans/enterprise-payg)** ## About this repository This repository contains the source code for the official [Unleash documentation](https://docs.getunleash.io). The site is built entirely by the [Fern CLI](https://buildwithfern.com/). API specs are committed to the repo and kept up to date by CI — you don't need to fetch them locally. ## Quickstart ### Prerequisites - [Node.js](https://nodejs.org/) 20+ (required to install and run the Fern CLI) - [Fern CLI](https://buildwithfern.com/learn/cli-api/cli-reference/global-options): `npm install fern-api` ### Clone and run ```bash git clone https://github.com/Unleash/unleash-documentation.git cd unleash-documentation fern docs dev ``` That's it. The dev server starts at `http://localhost:3000`. ## Command reference | Command | What it does | | --- | --- | | `fern docs dev` | Starts the local dev server. | | `fern check --strict-broken-links` | Validates the documentation and checks for broken links. | | `node scripts/fetch-openapi.mjs` | Manually refreshes the API specs from the hosted Unleash and Unleash Edge instances. Only needed if you want newer specs than what's committed. | ## How API specs are updated CI automatically fetches the latest OpenAPI specs from hosted Unleash and Unleash Edge instances on every push to `main` and every PR. The Unleash spec is split into three domains to keep the API reference navigable, and the Edge spec is published as its own reference: - **Admin API** (`fern/apis/admin-api/`): All endpoints except Client and Frontend. - **Client API** (`fern/apis/client-api/`): Client-tagged endpoints only. - **Frontend API** (`fern/apis/frontend-api/`): Frontend API-tagged endpoints only. - **Unleash Edge API** (`fern/apis/edge-api/`): Client and Frontend compatible endpoints exposed by Unleash Edge. You only need to run `node scripts/fetch-openapi.mjs` locally if you're working on API reference content and need a spec that's newer than the last CI run. ## How last-updated dates work A GitHub Action (`.github/workflows/update-last-updated.yml`) runs on every pull request and automatically adds or updates a `last-updated` field in the YAML frontmatter of any changed MDX file. You don't need to set this manually. ## Architecture - **Engine**: [Fern](https://buildwithfern.com/) - **API specs**: OpenAPI JSON files in `fern/apis/`, fetched by CI from a hosted Unleash instance - **Custom footer**: React component (`fern/components/CustomFooter.tsx`), server-side rendered by Fern - **Custom styling**: CSS overrides in `fern/styles.css`. For detailed architecture notes and conventions, see [CLAUDE.md](./CLAUDE.md). ## Contributing We welcome contributions. If you find something that's wrong, unclear, or missing, feel free to open an issue or submit a pull request. 1. Fork and clone this repository. 2. Create a new branch for your changes. 3. Run `fern docs dev` to preview locally. 4. Submit a pull request. For contributions to the Unleash product itself, see the main [Unleash repository](https://github.com/Unleash/unleash). ## Migration history This documentation was migrated to its own repository on 2 February 2026. It previously lived in the `website` folder of the main [Unleash repository](https://github.com/Unleash/unleash). You can find the commit history prior to the migration date in the [`Unleash/unleash`](https://github.com/Unleash/unleash) repository.