Vercel Microfrontends

Split a large application into independently deployable units that render as one cohesive app. Vercel handles routing on its global network using microfrontends.json.

Core concepts: default app (has microfrontends.json, serves unmatched requests) · child apps (have routing path patterns) · asset prefix (prevents static-asset collisions) · independent deployments.

Frameworks: Next.js (App Router + Pages Router), SvelteKit, React Router, Vite — all via @vercel/microfrontends.

CLI (vercel microfrontends / vercel mf):

• create-group — create a new group; interactive by default, or fully non-interactive with --non-interactive (options: --name, --project (repeatable), --default-app, --default-route, --project-default-route (repeatable, format: <project>=<route>, required for each non-default project in non-interactive mode), --yes to skip confirmation prompt); note: --non-interactive is blocked if adding the projects would exceed the free tier limit — the user must confirm billing changes interactively
• add-to-group — add the current project to an existing group; always asks for confirmation (there is no --yes), so it needs an interactive terminal, and it refuses to run with --non-interactive when adding would go past the free project limit (options: --group and --default-route pre-fill the prompts)
• remove-from-group — remove the current project from its group; requires interactive terminal (option: --yes skips project-link prompt only)
• delete-group — delete a group and all its settings, irreversible; requires interactive terminal (option: --group to pre-select group)
• inspect-group — retrieve group metadata (project names, frameworks, git repos, root dirs); useful for automating setup (options: --group, --format=json, --config-file-name)
• pull — pull remote microfrontends.json for local development (option: --dpl)
• microfrontends proxy — local dev proxy · microfrontends port — print auto-assigned port

Finding Detailed Information

This skill includes detailed reference docs in the references/ directory. Do not read all references upfront. Instead, search or grep the relevant file when the user asks about a specific topic:

Topic	Reference file
Getting started, quickstart, framework setup, microfrontends.json schema, fields, naming, examples	references/configuration.md
Path expressions, asset prefixes, flag-controlled routing, middleware	references/path-routing.md
Local proxy setup, polyrepo config, Turborepo, ports, deployment protection	references/local-development.md
Inspecting groups (inspect-group), adding/removing projects, fallback environments, navigation, observability	references/managing-microfrontends.md
Testing utilities (validateMiddlewareConfig, validateRouting, etc.), debug headers, common issues	references/troubleshooting.md
Deployment protection, Vercel Firewall, WAF rules for microfrontends	references/security.md

When the user asks about a specific topic, use grep or search over the relevant reference file to find the answer without loading all references into context.