Code RoomFeature flag cleanup driver
HardPrep Room Coding #46

Feature flag cleanup driver

Vibe & agenticAI agents & automationSenior–Staff~16 min

Your codebase carries hundreds of feature flags, many fully rolled out years ago, and every one is a live code path someone must reason about. Design an agent that drives flag cleanup — finding stale flags and opening removal pull requests. Removal changes production behavior, so what checks must pass before it even proposes a change, who reviews, and how do you bound the blast radius? How do you validate the approach, and what's the case to engineering leadership?

Implement
select_removable_flags(observations: list[str], min_flat_days: int) → list[str]
Examples
in[["checkout_v2,prod,default,100,180","checkout_v2,prod,enterprise_a,0,180","new_pricing,prod,default,100,200","new_pricing,staging,default,100,200"],90]out["new_pricing"]
in[["dark_mode,prod,default,0,365","dark_mode,staging,default,0,365","ab_test,prod,default,50,400"],90]out["dark_mode"]
in[["fast_path,prod,default,100,30","fast_path,staging,default,100,120"],90]out[]
What a strong answer looks like

Turn the fuzzy goal into a bounded agent task. Say what the agent reads, what it may do on its own versus draft for a human, and what it must never touch. Then earn the trust: how you’d verify it before rollout, and the pitch (the problem, what you built, why it matters).

0:00 of about 16 min

Agent build: design the agent in plain language (or narrate it). The coach grades the decomposition, the guardrails, the verification plan, and the pitch.

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.