/rollback

description: "Revert to a previous Shipyard checkpoint"
disable-model-invocation: true
argument-hint: "[checkpoint-tag] [--list]"

/shipyard:rollback - Checkpoint Rollback

You are executing the Shipyard rollback workflow. Follow these steps precisely.

<prerequisites>

Step 1: Verify State

1. Verify `.shipyard/` exists. If not, tell the user there is nothing to roll back. 2. Verify this is a git repository with at least one commit.

Step 2: List Checkpoints

Run `git tag -l "shipyard-checkpoint-*" --sort=-version:refname` to find all checkpoints.

• **If `--list` was passed**, display checkpoints with dates and labels, then stop.
• **If no checkpoints exist**, inform the user:

> "No Shipyard checkpoints found. Checkpoints are created automatically during `/shipyard:plan` and `/shipyard:build`."

</prerequisites>

<execution>

Step 3: Select Checkpoint

• **If a specific checkpoint tag was provided**, use it. Verify it exists with `git tag -l`.
• **If no argument**, show the 5 most recent checkpoints and ask the user to select one:

Available Checkpoints
═════════════════════

1. shipyard-checkpoint-post-build-phase-2-20260131T...
2. shipyard-checkpoint-pre-build-phase-2-20260131T...
3. shipyard-checkpoint-post-plan-phase-2-20260130T...
4. shipyard-checkpoint-post-build-phase-1-20260130T...
5. shipyard-checkpoint-pre-build-phase-1-20260130T...

Select a checkpoint (1-5):

Step 4: Choose Rollback Scope

Ask the user:

> "What scope should the rollback cover?" > 1. **State only** — Revert `.shipyard/` files only (plans, state, roadmap). Code stays as-is. > 2. **Full rollback** — Revert both `.shipyard/` state AND code changes back to the checkpoint.

Step 5: Create Safety Checkpoint

Before any rollback, create a safety checkpoint:

Follow **Checkpoint Protocol** (create a named git tag for rollback safety at key pipeline stages; see `docs/PROTOCOLS.md`) -- create `pre-rollback` checkpoint.

This ensures the current state can be recovered if the rollback was a mistake.

Step 6: Execute Rollback

State-only rollback:

git checkout <checkpoint-tag> -- .shipyard/

This restores all `.shipyard/` files to their state at the checkpoint without affecting code.

Full rollback:

Identify all commits between the checkpoint and HEAD:

git log --oneline <checkpoint-tag>..HEAD

Show the user what will be reverted. Then:

git revert --no-commit <checkpoint-tag>..HEAD
git commit -m "shipyard: rollback to <checkpoint-tag>"

Step 7: Update State

Add a history entry to `.shipyard/HISTORY.md`:

- [<timestamp>] Rolled back to <checkpoint-tag> (<scope>)

</execution>

<output>

Step 8: Confirm

Display: > "Rollback complete. Reverted to `<checkpoint-tag>` (<scope> scope)." > "Safety checkpoint created: `shipyard-checkpoint-pre-rollback-<timestamp>`" > "Run `/shipyard:status` to see current state."

</output>