build-until-pass

Build Until Pass

A bounded self-correcting loop: run the project's check command, capture its errors, apply the smallest diff that addresses the first failure, re-run, and repeat until it exits 0 — or until a hard attempt cap is hit.

The core principle: the check command is the judge, not you. You do not declare the build "basically fixed." Green is exit code 0. Anything else is red, and red means another round.

This is the engineering-discipline counterpart to "run it and hope." The cap exists so the agent backs off instead of burning tokens thrashing on an error it cannot fix without human input.

When to Use

• A build / compile / bundle command fails and the cause is mechanical (type errors, missing imports, signature mismatches, bundler config)
• tsc, cargo build, go build, npm run build, vite build exits non-zero
• A typecheck or lint gate is red and you want it green before committing
• A focused test suite is failing and each failure points at a clear fix
• CI went red on a build/typecheck step and you're reproducing locally
• You catch yourself copy-pasting errors back to the agent one at a time

When NOT to Use

• You don't know the check command yet — find it first (see Phase 0)
• The failure is a genuine logic bug needing investigation, not a mechanical fix → use debug-hypothesis instead, then come back here to confirm green
• The fix requires a product/design decision only a human can make
• The "fix" would mean deleting tests, // @ts-ignore-ing real errors, or loosening types to silence the compiler → that's cheating the judge, not passing it (see Anti-rationalizations)
• The build passes already — there's nothing to loop on

The Loop

            ┌─────────────────────────────────────────────┐
            │  attempt > MAX_ATTEMPTS (default 10)?        │
            │  → STOP, report what's left, ask the human   │
            └──────────────────────┬──────────────────────┘
                                   │ no
   RUN CHECK ──▶ green? ──yes──▶  DONE (exit 0, report rounds used)
       ▲             │
       │             │ no (red)
       │             ▼
       │      READ ERRORS  ──▶  FIX SMALLEST  ──▶  re-RUN
       │      first failure     minimal diff,        │
       │      only, verbatim    no refactor          │
       └──────────────────────────────────────────────┘
                    one round = one fix + one re-run