strapi-version-upgrade

name	strapi-version-upgrade
description	Upgrade a Strapi application to a new version. ALWAYS reviews the relevant breaking changes first (via the strapi-docs MCP server, or by fetching the docs directly if the MCP is unavailable), then performs the upgrade using the official @strapi/upgrade tool. Use whenever the user wants to upgrade, update, or bump their Strapi version.

Strapi version upgrade

Upgrade a Strapi project to a target version. This skill enforces two hard rules:

1. Always check breaking changes before upgrading. Never run the upgrade without first reviewing the breaking changes that apply between the current version and the target.
2. Always use the @strapi/upgrade tool to perform the upgrade. Never upgrade by manually editing package.json or running npm install @strapi/strapi@x directly.

Follow the steps below in order.

Step 1 — Determine current and target versions

1. Read the project's current Strapi version from package.json (@strapi/strapi under dependencies). If there is no Strapi project in the working directory, stop and tell the user.

2. Determine the latest published version:

   npm view @strapi/strapi dist-tags
   

   The latest tag is the newest stable release. legacy is typically the latest v4.

3. Establish the target. If the user named a version or release type (major/minor/patch/latest/a specific x.y.z), use it. Otherwise default to latest and confirm with the user.

4. Classify the jump using semantic versioning: compare the major/minor/patch of current vs. target. Only a change in the major number introduces breaking changes. Minor and patch releases are backward-compatible by definition.

Step 2 — Check breaking changes (MANDATORY, before any upgrade)

Use the strapi-docs-mcp skill / strapi-docs MCP server if it is available; otherwise fetch the docs directly. Do not skip this step even for patch upgrades.

If the strapi-docs MCP server is available

Query it for the breaking changes between the current and target versions, e.g.:

"What are the breaking changes when upgrading Strapi from <current> to <target>?"

Quote the exact breaking-change titles and note which are handled by codemods vs. which require manual work.

If the MCP server is NOT available

Fetch the breaking changes page directly (no auth needed). Prefer the flat Markdown form:

• Major-version migrations (e.g. v4 → v5): https://docs.strapi.io/cms/migration/v4-to-v5/breaking-changes.md

Use WebFetch on the .md URL (append .md to any docs.strapi.io page to get flattened Markdown with nothing hidden in tabs/accordions). If a page 404s as .md, retry the HTML URL.

Make the report concrete — scan the codebase

Do not stop at a generic list from the docs. For each breaking change, grep the project's own source to see which ones actually apply, and turn the summary into a project-specific list. Concretely:

• Read src/index.{js,ts} (the app's register/bootstrap entry) for patterns the breaking changes touch.
• Scan the project's controllers, services, and route files (src/api/**) — the upgrade tool's codemods cover common patterns, but custom logic often uses APIs a breaking change renames or removes.
• Read the content-type schemas (src/api/**/content-types/**/schema.json and src/components/**) for attributes affected by breaking changes — e.g. attribute types that changed, or attribute names that collide with new reserved/system names.
• Check package.json and config/plugins.{js,ts} for third-party plugins whose compatibility may be affected.

Use each breaking-change title as a search seed (grep for the removed/renamed API, the deprecated option, the reserved name). Report which files match which breaking change so the user sees exactly what the upgrade will touch versus what they'll need to fix by hand.

Report and gate

• Same major (minor/patch upgrade): State clearly that there are no breaking changes — the breaking-changes database is scoped to major migrations only. You still performed the check; say so.
• Major upgrade: Summarize the applicable breaking changes grounded in the codebase scan above, flag which are handled by codemods versus which need manual code updates, call out any reserved-name collisions (these may need a database migration — see Step 7), and stop and wait for the user's affirmative reply before proceeding — do not continue in the same turn.

Step 3 — Pre-flight safety

Remind the user to back up codebase and database before upgrading (default SQLite DB is .tmp/data.db). The upgrade tool also checks for a clean git working tree as an optional requirement, so a committed/clean tree eases rollback.

Offer a dry run first to preview changes without modifying files:

npx @strapi/upgrade <target> --dry

Step 4 — Check the running Node version (before running the tool)

The @strapi/upgrade tool is itself a Node CLI: it runs under whatever Node npx is invoked with, and it declares the same Node requirement as the target Strapi. So the running Node — not just package.json's engines — must satisfy the target's range before you run the tool. If it doesn't, both the upgrade run and the subsequent app boot happen on an unsupported runtime.

1. Read the currently running Node version (node -v).

2. Read the Node range the target Strapi supports:

   npm view @strapi/strapi@<target-x.y.z> engines
   

   (Cross-check against the docs' recommended Node for that major — Strapi recommends the active LTS.)

3. If the running Node already satisfies the target's range, continue to Step 5.

4. If it does not, Node must be upgraded before the upgrade. How you handle this depends on whether the user has a Node version manager — check for one before deciding (look for nvm, fnm, or volta on PATH, and for a .nvmrc / .node-version / Volta field in the repo):

   • If a version manager is present: prompt the user to ask whether they want you to upgrade the Node version for them, and gate on their confirmation before any runtime change. Only if they confirm:
     • Pick a Node version inside the target's range, preferring an LTS release the target lists.
     • Switch via their version manager (never a global install) so the change is reversible — the old Strapi can still run on the old Node if a rollback is needed. Suggest pinning it in the repo (.nvmrc / .node-version / Volta field) so CI and teammates move together.
   • If no version manager is present: do not attempt to change the system Node yourself — a global runtime swap is risky and not cleanly reversible. Instead, tell the user to fix the Node version on their own, and recommend they do it by installing a version manager first (nvm, fnm, or volta), then selecting a Node version inside the target's range. Stop and wait for them to sort the runtime out before continuing.
   • Do not reinstall node_modules immediately after switching Node. At that point package.json still pins the old Strapi, so a clean install would rebuild the old dependency tree against the new Node — which, if the ranges are disjoint (below), can fail the engines check or leave native modules built against the wrong ABI, breaking the working state before the tool has moved you forward. The clean reinstall belongs Step 5, once the tool has rewritten to the target (see Step 7d).

Step 5 — Run the upgrade with the upgrade tool

Run the official tool from the project root. Choose the command form that matches the target:

npx @strapi/upgrade latest          # newest stable version
npx @strapi/upgrade major           # next major (requires being on latest patch of current major first)
npx @strapi/upgrade minor           # latest minor+patch in current major
npx @strapi/upgrade patch           # latest patch in current minor
npx @strapi/upgrade to <x.y.z>      # a specific published version

Notes:

• major is gated: the project must already be on the latest patch of its current major. If it isn't, run minor first, then major.
• Use to <x.y.z> when latest is blocked by a registry policy (e.g. min-release-age in .npmrc) or when the user wants an exact version. to skips the major-safety check intentionally.
• For pre-releases, add --codemods-target <x.y.z>.
• Useful flags: -y/--yes (auto-confirm prompts), -d/--debug (verbose), -p/--project-path <path> (non-cwd project). Avoid -y/--yes for major jumps — it auto-confirms every prompt, including the major-version safety prompt on latest. Prefer interactive mode (or explicit per-step user approval) unless the user asked for an unattended run.

The tool updates dependencies, installs them, and runs codemods for the target version. Do not substitute a manual package.json edit or a bare npm install for this step.

If the install phase fails (e.g. ERESOLVE), first retry with a clean node_modules and lockfile (rm -rf node_modules package-lock.json && npm install) before falling back to any manual dependency edits — a stale lockfile from the old major is the most common cause and a clean reinstall usually resolves it.

Step 6 — Fix the engines field

The upgrade tool updates dependencies but does not touch package.json's engines field. A stale engines.node range left over from the old major can fail the compatibility check and block install (npm/yarn/pnpm) after the upgrade. (This is the declared range in package.json — distinct from the running Node you checked in Step 4.)

1. Read engines from the project's package.json.
2. Reuse the target's Node range from Step 4 (npm view @strapi/strapi@<target-x.y.z> engines).
3. If the project's engines.node is narrower than or incompatible with the target's, offer to replace it with the correct range for the target major, and apply the edit once the user confirms. Leave it alone if it's already compatible.

Step 7 — Post-upgrade: codemod gaps, plugins, migrations

Run these in order. Each destructive or code-changing action pauses for the user to confirm — the user is in charge of every change beyond what the tool applied automatically.

7a — Review and offer to fix the codemod gaps

1. Tell the user to review the changes the tool made (especially codemod edits and package.json) before restarting the app.
2. Codemods cover common patterns, not everything. Cross-reference the breaking changes flagged as "manual" in Step 2 against the code the codemods actually changed. For anything still unhandled, ask the user whether they want you to attempt the fixes in application code — then wait for their affirmative reply; do not start editing in the same turn. Only edit code after they confirm, and edit after the tool's codemods have been applied (never before — you'd fight the codemods).

7b — Upgrade incompatible third-party plugins

If any third-party plugin (from Step 2's package.json/config/plugins scan, or surfaced by install/boot errors) is not compatible with the target Strapi version:

1. Identify a plugin version that supports the target (npm view <plugin> versions / its peer-dependency range on @strapi/strapi).
2. Ask the user before upgrading each plugin individually — confirm every plugin bump separately; never batch-upgrade plugins silently.
3. Apply the confirmed version bump and reinstall.

7c — Reserved-name collisions → custom database migration

If Step 2 found an attribute whose name collides with a new reserved/system name in the target major, a rename is required and renaming a column risks data loss. In that case:

1. Ask the user whether to proceed with the rename at all.
2. If yes, ask whether you should generate a database migration to preserve existing data during the rename.
3. Require an explicit backup confirmation before writing or running any migration. The migration executes against the real database on next boot and the rename is not cleanly reversible, so ask the user to confirm they have manually backed up the database — then stop and wait for a clear "yes" in a separate reply; do not continue in the same turn. Do not proceed on a vague answer, and never take the backup on their behalf as a substitute for their confirmation. If they have not backed up, stop and let them do it first.
4. Only after that confirmation, author the migration following reference.md (placement, ordering gotchas, data-safe rename, system-column collisions, idempotency, down()). Do not hand-wave this — the ordering and collision rules there prevent both boot failures and silent data loss.

7d — Verify

1. For major upgrades, note that Strapi's built-in data migrations run automatically on first startup in the new major — the upgrade tool does not migrate data itself, and any custom migration in ./database/migrations/ also runs then.
2. If Node was switched in Step 4, do a clean reinstall now — after the tool has rewritten package.json to the target, not before: rm -rf node_modules && install. Native modules (better-sqlite3, sharp, …) are compiled against a specific Node ABI; a stale build left over from the old Node is the most common "changed Node and it won't boot" failure and is easily misread as an upgrade bug.
3. Verify: reinstall if needed, rebuild the admin, and start the app to confirm it boots cleanly.