Feature Flags

Deep feature flag workflow—taxonomy, targeting, lifecycle, safety and kill switches, cleanup, and governance. Use when shipping gradually, experimenting, or decoupling deploy from release.

Flags decouple deploy from release—and become debt if never removed. Taxonomy, ownership, and retirement matter as much as targeting.

When to Offer This Workflow

Trigger conditions:

• Gradual rollouts, kill switches, or experiments behind flags
• Flag sprawl and unknown defaults
• Client vs server evaluation and hydration flicker

Initial offer:

Use six stages: (1) taxonomy, (2) targeting rules, (3) evaluation & consistency, (4) safety & ops, (5) lifecycle & cleanup, (6) governance). Confirm provider (LaunchDarkly, Unleash, ConfigCat, homegrown).

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Stage 1: Taxonomy

Goal: Separate short-lived release flags, long-lived config flags, and experiment flags tied to analytics.

Exit condition: Naming convention and expected TTL per type.

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Stage 2: Targeting Rules

Goal: Percentage rollouts, segments (tenant, plan, region), deterministic bucketing (stable user key).

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Stage 3: Evaluation & Consistency

Goal: Server-side authoritative for security and billing; client flags for UX only; avoid UI flicker on hydration (SSR/CSR agreement).

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Stage 4: Safety & Ops

Goal: Kill-switch runbook; audit trail for changes; safe defaults when provider unavailable (often “off”).

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Stage 5: Lifecycle & Cleanup

Goal: Tickets to remove flags after full rollout; periodic audits; metric for stale flags.

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Stage 6: Governance

Goal: Approvals for broadening exposure; promotion across environments; break-glass access for incidents.

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Final Review Checklist

• Flag types and naming documented
• Targeting and bucketing deterministic
• Server vs client boundaries clear
• Kill switches and defaults documented
• Cleanup process and ownership

Tips for Effective Guidance

• Never put security-only gates solely in client-side flags.
• Pair with ab-testing when experiment analysis is primary.

Handling Deviations

• Align with release-management for communication cadence.