Overrides
Targeted flag values for PRs, previews, and specific users.
An override pins a flag to a specific value for a narrow audience — usually a single PR's preview deployment, or a handful of internal users — without touching the global rollout.
PR-scoped overrides
flagctl preview set checkout.v2=on --pr 482
While PR #482 is open, any request carrying X-Flagctl-Preview: 482 sees checkout.v2 = on. Other traffic is untouched.
TTL expiry
Every override gets a TTL (default 7 days). After expiry, flagctl reverts the override and writes an audit entry. You can extend with flagctl preview extend.
Auto-revoke on close
When the linked PR closes (merged or not), the GitHub webhook revokes any overrides scoped to it within seconds.