workflow-feature-flag — Gate → Rollout → Monitor → Promote or Rollback

Shipping code and switching it on are two separate acts. A feature flag lets you deploy on your schedule, enable for specific users or a percentage of traffic, and kill it instantly if anything goes wrong — without a rollback deploy. This skill gives that discipline to any feature.

Phase 0: Detect existing flag infrastructure

package.json         → launchdarkly-node-server-sdk, @launchdarkly/js-client-sdk,
                       flagsmith, growthbook, unleash-client, posthog-js
.env.*               → LD_SDK_KEY, FLAGSMITH_ENV_KEY, GROWTHBOOK_API_HOST,
                       POSTHOG_KEY (reference by name only)
src/lib/flags.*      → custom feature-flag utility
src/config/flags.*   → env-var-based flags