---
name: migrate-internal-package
description: Move a package from another TryGhost repository into Ghost as an internal-only workspace package while preserving its Git history. Use for package migrations from repositories such as TryGhost/SDK or TryGhost/framework, including the history import PR, exceptional merge-commit handoff, source-repository removal PR, optional npm deprecation, migration cleanup, and modernization handoff.
---

# Migrate an internal package into Ghost

Move a package from another TryGhost repository into Ghost without losing its
history or creating a period where neither repository owns it. Keep migration
mechanics separate from Ghost's lifetime package standards.

## Authority boundaries

Explain every cross-repository or administrative action before it happens.

- A request for instructions is not permission to perform the action.
- If the user says "tell me how, I do it", provide the command and wait.
- Require explicit authorization before changing repository settings, merging a
  PR, deprecating npm versions, or force-pushing.
- Never ask for, display, or store credentials or OTPs.

## Work in isolated checkouts

Never manipulate history in a checkout containing unrelated work. Fetch both
repositories, confirm the source checkout is clean, and create a dedicated
Ghost worktree from the freshly fetched `origin/main`.

Run history-changing commands individually or in a fail-fast shell. A failed
`git worktree add` must not be followed by `git subtree add` in whichever
checkout happens to be current. Before choosing a branch or path, list existing
worktrees and matching local and remote branches. Use a migration-specific slug,
for example `codex/import-<package>-from-<source>`, rather than a generic name.

If the destination branch or path already exists, stop and inspect its
cleanliness, base, divergence, source split and attached worktree. Do not mutate,
delete or silently reuse it. Present the evidence and ask the user whether to
resume, preserve and supersede, or remove it when more than one choice is
reasonable. A previous attempt can contain valid unmerged history even when its
remote branch is gone.

Before importing, record and compare the destination `HEAD` and `origin/main`;
they must match. Recheck the first parent immediately after the subtree commit.

## Confirm this workflow applies

Before changing either repository, record the source repository, its default
branch, the package path within it, the destination path in Ghost, and whether
the package has been published to npm. Then:

1. Find every Ghost and source-repository reference to the package name and
   directory.
2. Inspect its npm metadata, README, documentation, release configuration and
   known public consumers.
3. Confirm Ghost is the real owner and can consume it via `workspace:*`.
4. Identify any need for independent releases or supported external use.

Publication or download counts alone do not prove that a package must remain a
supported public API. If supported external consumers still need new releases,
stop: this internal-only workflow is the wrong publishing model.

For the public-consumer audit, check npm metadata, first-party repositories and
documentation, plus GitHub code search for package dependencies and runtime
imports. Classify results as first-party consumers, independent integrations,
Ghost forks, or deployed Ghost installation snapshots. Forks and installation
snapshots show historical presence only. Require a recent update, current
deployment, active dependency or another freshness signal before treating them
as evidence of continued installation needs; even then, they do not establish
an independently supported API. Record the evidence and confidence behind the
ownership decision; stop and ask if current support expectations remain
unclear.

Run registry-only `npm view` commands from a neutral temporary directory. A
repository's `devEngines` policy can reject the host Node version before npm
contacts the registry, which is unrelated to the package metadata audit. Record
that failure separately if using a neutral directory does not resolve it.

## Produce these work products in order

1. A green Ghost import PR with reachable source history.
2. After it merges, a green source-repository removal PR.
3. npm deprecation if the package was published and new direct use is
   unsupported.
4. A focused Ghost cleanup PR for stale migration-specific automation.
5. A Ghost modernization PR assessed against the current package template and
   comparable internal packages.

Keep the history import and modernization separate. The import establishes
ownership and provenance; later commits can modernize code without obscuring
the move.

## 1. Import the history into Ghost

Read
[`references/history-and-merge.md`](references/history-and-merge.md) completely
before manipulating history.

Use an unsquashed `git subtree` import from the recorded source repository and
package path. Do not copy the current files, pass `--squash`, or recreate old
commits manually.

After the subtree commit, add focused integration commits that:

- make the package private with an internal placeholder version;
- set `ghostPackage.goldenPath` to `migration` and `ghostPackage.reason` to a
  concise explanation of the remaining modernization work;
- switch Ghost consumers to `workspace:*`;
- update the lockfile with `pnpm`;
- minimally adapt configuration and tests to work in Ghost;
- retain runtime behavior for the later modernization PR.

Before editing package metadata, map each source `workspace:*` dependency to
its destination state:

- use `workspace:*` when the dependency already exists in Ghost;
- use `catalog:` when Ghost's catalog version satisfies the imported package;
- add a named migration catalog with the exact published version when changing
  the shared catalog would broaden the migration or alter runtime behavior;
- stop if a required dependency is unpublished or exists only in the source
  workspace.

Document temporary named-catalog entries for the modernization follow-up. Never
inline dependency versions; Ghost's strict catalog policy still applies. Do not
import additional packages implicitly.

If the package is legacy JavaScript or CommonJS, read
[`references/legacy-integration.md`](references/legacy-integration.md)
completely before creating integration commits.

Verify that the subtree commit has two parents and that representative file
history crosses into the source repository before opening the PR.

Before opening the PR, also verify the source split is reachable from the branch
tip, the consumer resolves the workspace package through its production import
path, package lint and tests pass through Nx, relevant consumer tests pass, the
full build passes, and the Ghost archive contains the internal package. Record
the exact commit IDs and commands in the handoff.

For a pilot or first use, include a structured gap report in the handoff:

- `Observed`: the exact failure or ambiguity and the command/state that exposed it;
- `Worked around`: the safe action taken, without hiding the original gap;
- `Skill change`: the concrete instruction, preflight or script improvement;
- `Tooling change`: anything that cannot be solved within this repository;
- `Confidence`: high, medium or low, with unresolved evidence called out.

## 2. Merge the import without rewriting history

This is the exceptional PR. It must use GitHub's **Create a merge commit**
method:

- squash merge discards the imported ancestry;
- rebase merge cannot preserve the subtree merge topology.

Make CI green, then stop at the merge checkpoint. If the merge-commit option is
disabled, an authorized org admin should run:

```bash
.agents/skills/migrate-internal-package/scripts/merge-history-pr \
    TryGhost/Ghost \
    <pr-number> \
    <source-split-tip> \
    --confirm
```

An agent without admin authority should provide that exact handoff rather than
attempting a workaround. The script performs preflight checks, records and
temporarily changes the setting, uses the correct merge form, restores the
setting, and verifies the resulting history.

Afterward, independently fetch `main` and confirm the source split tip is an
ancestor before starting source-repository cleanup.

## 3. Remove the package from the source repository

Branch from the latest source default branch only after the Ghost import is
verified on `main`. Remove:

- the package directory;
- workspace and lockfile entries;
- release, Changesets and publishing configuration;
- package-specific Renovate rules;
- tests, documentation and examples that claim source-repository ownership;
- remaining source-repository consumers or imports.

Search with both the npm name and directory name. The source-repository PR
should link to the merged Ghost PR and state that Ghost now owns the
implementation. Use that repository's normal merge policy; this PR does not
contain imported ancestry.

## 4. Deprecate npm when appropriate

If the package was published and new direct use is now unsupported, deprecate
all historical versions rather than unpublishing them:

```bash
npm deprecate '@tryghost/<package>@*' \
  'This package is now maintained as an internal Ghost workspace package. Existing versions remain available for older Ghost releases; direct use is unsupported.'
npm view @tryghost/<package> deprecated
```

This preserves installation for old Ghost releases. Authentication and OTP are
human checkpoints; verify the public metadata after the authorized user runs
the mutation.

## 5. Remove migration-specific automation

Search `.github/renovate.json5` and related release automation for rules that
still treat the package as sourced or released from the former repository or
npm. Prefer a small,
standalone cleanup PR so the later conversion remains focused.

## 6. Hand off to the package golden path

Read `packages/README.md` completely and compare the package against the
template and current comparable internal packages. Do not turn this one-time
migration skill into the source of lifetime package standards.

If the package needs conversion from legacy JavaScript or CommonJS, use the
`convert-internal-package-to-typescript` skill in a separate modernization PR.
That skill owns commit staging, file-lineage checks, TypeScript quality and
runtime verification. This does not alter the merge-commit requirement for the
earlier subtree history import.

## Completion criteria

Do not call the migration complete until:

- the source split history is reachable from Ghost `main`;
- Ghost consumes the workspace package;
- the source repository no longer consumes or publishes it;
- npm status matches the chosen support policy;
- stale migration automation is gone;
- the package satisfies the repository's current internal-package standards;
- relevant package, consumer and archive checks pass;
- temporarily changed repository settings are restored.

At each boundary, distinguish what is merged from what is merely prepared and
report the exact verification performed.

## Exclusions

Do not use this workflow for packages that remain public, independently
versioned, or supported for third-party use. This skill describes privileged
operations but does not authorize them.
