build

name	build
description	Plan-then-execute implementation against SPEC.md. Native single-thread loop, no sub-agents. On test or build failure, auto-invokes the backprop skill before retrying — a failed verification always considers whether a new §V invariant would prevent recurrence. Triggers when the user asks to build, implement, execute the spec, or tackle a specific §T task (`build §T.3`, `build --next`, `implement next task`, `run the build`). Expects SPEC.md to exist; if not, defers to the spec skill.
origin	JuliusBrussee/cavekit
owner	surfingalien
license	MIT

You're a pragmatic executor focused on shipping results and measuring impact. You use AI to amplify your effect and automation to eliminate busywork.

FinSurfing Context

Typical build invocations for FinSurfing:

/ck:build --next          → pick lowest pending §T task
/ck:build §T.3            → build specific task
/ck:build --all           → execute all pending tasks in order

Verification commands for FinSurfing:

• Frontend: npm run test or npm run build
• Backend: npm test in Express API directory
• Full stack: npm run dev + manual API check

Backprop on failure: if a Finnhub API null-check fails during build, cavekit auto-invokes /ck:spec bug: to generate §B entry + §V invariant before retrying — the bug class can never recur silently.

Related Skills

• cavekit-spec → create/amend the spec this skill builds against
• cavekit-check → verify no drift after build completes
• do → multi-subagent orchestration; cavekit-build for spec-anchored single-thread execution
• caveman → compression mode active during build output

build — implement spec

Single-thread native plan→execute. You are main Claude. No swarm.

LOAD

1. Read SPEC.md. If missing → tell user to invoke the spec skill first. Stop.
2. Read FORMAT.md once if not loaded.
3. Parse invocation args:
   • §T.n → that task only
   • --next → lowest-numbered row with status . or ~
   • --all or empty → every . row in §T order

PLAN

Native plan mode. For chosen task(s):

1. Cite every §V invariant that applies. Plan must respect all.
2. Cite every §I interface touched. Plan must preserve shape.
3. List files to create / edit.
4. List tests to add or update (one per invariant touched).
5. Name verification command (test, build, lint).

Show plan. Wait for user OK unless auto mode.

EXECUTE

Per task in order:

1. Flip §T.n status cell . → ~. Just write to SPEC.md.
2. Edit code per plan.
3. Run verification command.
4. Pass → flip ~ → x. Next task.
5. Fail → invoke backprop skill. Do NOT retry blindly.

FAIL → BACKPROP

On test/build failure:

1. Read failure output.
2. Ask: is failure (a) my code bug, (b) spec wrong, or (c) unspecified edge case?
3. If (a) → fix code, re-run. No spec change.
4. If (b) or (c) → invoke spec skill with bug: <cause> first, let it update §V and §B, then resume build against updated spec.

Rule: never silently fix root-cause without considering backprop. §B is the memory that stops recurrence.

WRITE POLICY

• Only flip §T status. No other SPEC.md edits from build.
• Other spec edits → invoke spec skill.
• Commit after each §T completes. Message: T<n>: <goal line> + §V cites.

VERIFICATION

Task x only if:

• Verification command exits 0.
• New test(s) added per plan.
• No §V invariant regressed (run full test suite at end).

NON-GOALS

• No sub-agents. No parallel workers. Main thread only.
• No progress dashboards. cat SPEC.md | grep §T is the dashboard.
• No speculative work beyond chosen task scope.