feature-flagslisted

# Feature Flags (pointer) SDK code, targeting rules syntax and dashboard integration drift on each vendor release and are canonical at: - **LaunchDarkly** — [launchdarkly.com/docs](https://launchdarkly.com/docs) (SaaS, advanced targeting + experimentation) - **Unleash** — [docs.getunleash.io](https://docs.getunleash.io) (self-hosted open source) - **ConfigCat** — [configcat.com/docs](https://configcat.com/docs) (SaaS, generous free tier) - **PostHog Feature Flags** — [posthog.com/docs/feature-flags](https://posthog.com/docs/feature-flags) (paired with product analytics; see also recipe) - **OpenFeature** — [openfeature.dev](https://openfeature.dev) (vendor-neutral SDK standard — use to avoid lock-in) ## Use-case taxonomy (version-agnostic) | Type | Purpose | Lifetime | |---|---|---| | **Release toggle** | Deploy inactive code; flip on after smoke test | Short (days/weeks) | | **Experiment toggle** | A/B test; emits exposure events for analysis | Bounded by experiment duration | | **Ops toggle** | Circuit breakers, kill switches, degraded modes | Long-lived | | **Permission toggle** | Feature gating by role/plan/cohort | Permanent (treat like config) | Choose by lifetime: short → cheap implementation, long-lived → invest in observability + naming discipline. ## Foundation discipline (keep across releases) - **Default OFF**: every flag defaults to its conservative value (usually off). A flag that ships defaulting to ON is a hidden behaviour change. - **2-sprint rule**: r