Packages

The @molecule/* ecosystem: {{packages}} composable packages, how to find them, install them, and read their docs.

What packages are

Everything molecule builds with is a **@molecule/* package** — 1004 of them, all open source (Apache-2.0) and published to npm. Two broad families:

API packages — server capabilities: databases, auth, email, payments, files, AI providers, resources with full CRUD routes, and testing tools like the mock server.
App packages — client capabilities: the UI framework and class map, React/Vue/Svelte bindings, auth modals, maps, charts, i18n locales, e2e preview.

Packages are small and composable by design — api-emails-mailgun sends email through Mailgun; api-emails is the interface it implements. You install what you use, and the scaffold resolves transitive companions (locale bonds, default providers) automatically.

Finding packages

Search by capability, not by name — the way you’d ask a colleague:

npx mlcl search "send emails" --stack api
npx mlcl search "social login"
npx mlcl search "payments"

The same catalog is browsable at molecule.dev/packages — grouped by category, each package with its own page, and everything concatenated in llms-full.txt for agents.

Installing and wiring

A plain npm install gets you the code; `mlcl add --inject` also wires it — writes the dependency, generates the bond wiring, adds migrations and routes in one step:

npx mlcl add @molecule/api-emails-mailgun --inject
npx mlcl inject --dry-run    # preview what wiring would change; touch nothing

Note

New conversations in the IDE pick packages for you the same way — describe the capability and the scaffold installs and wires the right package.

Package docs

Every package’s README is generated from its own source — the usage examples and gotchas in it are guaranteed to match the code you installed. Read it three ways:

on disk: node_modules/@molecule/<name>/README.md
on the web: molecule.dev/packages/<name>
from an agent: the read_package_doc MCP tool