Feature Flags Architect

End-to-end feature flag design, rollout, and lifecycle management. Covers flag taxonomy (release vs ops vs experiment vs permission), gradual rollout patterns with blast-radius math, kill-switch runbooks, governance (who can flip what), and the flag-debt cleanup loop that keeps a codebase from drowning in stale flags.

This skill is provider-agnostic: the patterns work whether you run LaunchDarkly, Statsig, Unleash, Flagsmith, ConfigCat, GrowthBook, OpenFeature, or a homegrown system backed by Redis/DynamoDB/Postgres.

Core Capabilities

• Flag taxonomy — classify every flag as one of four types (release, ops, experiment, permission); the type sets lifetime, who flips it, and auto-expiry.
• Rollout ramps — dogfood → canary → 100% schedules with per-step blast-radius math and ramp templates by change type.
• Kill switches — ops-flag pattern with fail-open/closed decisions, runbooks, and alerting for risky dependencies or code paths.
• Governance — role-based who-can-flip-what matrix plus audit-log/retention requirements, mappable onto any flag system.
• Flag debt cleanup — quarterly inventory → classify → decide → execute → measure loop to keep flag count flat or shrinking.
• End-to-end workflows — add a release flag, build a kill switch, audit flag debt, flag-based rollback after a bad release.

Flag taxonomy — the four types

Every flag belongs to exactly one of these four types. The type determines the lifecycle, who can flip it, and whether it should auto-expire. Mixing types in one flag is a root cause of flag debt.