# Overview How plugins extend an installation, and which ones ship with the platform. Plugins are third-party integrations loaded by your installation. Each one is a folder in the installation's plugins directory — the **directory name is the integration id** — default-exporting a module that satisfies the `Integration` contract from `@headless-lms/core/types`. Composition scans that directory at startup, so adding an integration is adding a folder; there is nothing else to register. ```ts title="main.ts" const container = await createContainer(config, { pluginsDir: fileURLToPath(new URL("./plugins/", import.meta.url)), }); ``` A plugin folder can be a thin re-export of a published package — the reference installation's `plugins/slack/index.ts` just re-exports `@headless-lms/plugin-slack`. ## Available plugins | Plugin | Package | What it does | | --- | --- | --- | | [Slack](/docs/plugins/slack) | `@headless-lms/plugin-slack` | Posts domain events (e.g. entitlements) to a Slack channel | | [Plate editor](/docs/plugins/content-plate) | `@headless-lms/content-plate` | Notion-style activity content editor for the admin app | ## Writing your own Implement the `Integration` contract from `@headless-lms/core/types` (the zod helpers in `@headless-lms/core/integrations` cover input validation), drop the folder into your installation's plugins directory, and restart. Integration packages depend only on `@headless-lms/core` — never on the server. Each context exports the domain event types it owns, so a handler for entitlement events imports them from `@headless-lms/core/entitlements`.