/sdlc-implement

June 20, 2026 · View on GitHub

Implements a single Linear issue or free-form spec using fullstack-engineer + the ralph-loop skill for self-correcting retry logic. Works independently of the full /sdlc pipeline.

Usage

/sdlc-implement SAI-41                          # Linear mode: reads issue from Linear
/sdlc-implement "add JWT refresh token logic"   # Free-form mode: infers DoD from spec

STEP 1: Detect Input Mode

Inspect the argument:

  • If it matches the pattern [A-Z]+-[0-9]+ (e.g. SAI-41, LIN-123) → Linear mode
  • Otherwise → Free-form mode

STEP 2: Read Spec + Extract DoD

Linear Mode

Use the Linear MCP to fetch the issue:

mcp__linear-server__get_issue({ id: "<ARGUMENT>" })

Extract from the response:

  • Title — used as the commit subject
  • Description — full context for the engineer
  • Acceptance criteria — the checklist under "## Acceptance criteria" or "## DoD" becomes the Definition of Done

If no explicit AC section exists, infer DoD from the description: turn each "should", "must", or imperative statement into a checkbox.

Free-Form Mode

The argument string is the spec. Infer DoD by breaking the spec into verifiable outcomes:

  • What file(s) should exist or change?
  • What behaviour should be observable?
  • What should typecheck + tests confirm?

Write the inferred DoD as a checklist (3–5 items minimum).

STEP 3: Load Ralph Loop Skill

Read skills/ralph-loop/SKILL.md to load the self-correcting loop methodology into context before invoking the engineer.

STEP 4: Invoke fullstack-engineer

Spawn the fullstack-engineer agent with the following context:

Spawn: Agent({
  name: "fullstack-engineer",
  description: "Implement: <title or spec summary>",
  prompt: "
    ## Spec
    <full issue description or free-form spec>

    ## Definition of Done
    <DoD checklist extracted in Step 2>

    ## Instructions
    Implement the spec above. Apply the ralph-loop skill:

    ### Inner Loop (apply per implementation attempt)
    1. Run sentinel checks before verifying:
       - Context drift: are you still addressing the full spec?
       - Spec drift: are you writing code outside the declared scope?
    2. Implement the changes.
    3. Verification gateway:
       - Run typecheck: `npm run typecheck` or `tsc --noEmit` (adapt to project)
       - Run relevant tests: `npm test` or equivalent
    4. If all checks pass → DoD satisfied, stop.
    5. If checks fail → retry with fresh context:
       - Re-read the spec + DoD
       - Pin the failure output at the top of your reasoning
       - Do NOT carry forward previous reasoning
       - Max 2 retries. If still failing after 2 retries → stop and surface failure.

    ### Circuit Breaker
    After 2 failed retries: report what failed, what you tried, and what the blocking error is.
    Do not attempt further changes — surface to the user.
  "
})

Wait for fullstack-engineer to complete.

STEP 5: Evaluate DoD

After the engineer completes, check each DoD item:

  • All acceptance criteria satisfied?
  • Typecheck passes?
  • Relevant tests pass?
  • No unintended files modified outside the spec scope?

If the circuit breaker fired (2 retries exhausted), report the failure and stop — do not proceed to review or commit.

STEP 6: Run /review

If DoD is satisfied, run /review scoped to the changed files:

# Identify changed files
git diff --name-only HEAD

# Review surfaces any correctness or quality issues
/review

If review surfaces blocking issues, surface them to the user before committing.

STEP 7: Commit

Commit all changes to the current branch.

Commit message format:

  • Linear mode: Use the issue title verbatim as the subject line, followed by the issue ID in the footer. 
    <Issue title>

Closes <ISSUE-ID>
  • Free-form mode: Use a concise imperative summary of the spec as the subject line. 
    <imperative summary of spec>

No "Co-Authored-By", "Generated with", or AI attribution lines.

git add <changed files>
git commit -m "<subject>"

Completion Output

✅ /sdlc-implement complete

Mode: <Linear | Free-form>
Issue: <ID and title, or spec summary>

DoD satisfied:
  ✅ <criterion 1>
  ✅ <criterion 2>
  ...

Files changed:
  <list of modified/created files>

Commit: <short hash> — <subject>

Error Output (Circuit Breaker)

❌ /sdlc-implement: circuit breaker fired after 2 retries

Spec: <title or summary>

Last failure:
  <typecheck / test failure output>

What was tried:
  Attempt 1: <brief description>
  Attempt 2: <brief description>

Action required: Review the failure above and either clarify the spec or fix the blocking issue manually.

Rules

  • Load ralph-loop skill before invoking the engineer — it is not optional
  • Typecheck + tests must pass before DoD is declared satisfied
  • Do not retry more than 2 times — surface failures, don't loop silently
  • Do not commit if DoD is not satisfied
  • Do not add AI attribution to commits