> ## Documentation Index > Fetch the complete documentation index at: https://docs.twenty.com/llms.txt > Use this file to discover all available pages before exploring further. # Apps > Extend Twenty with code — custom objects, server-side logic, UI components, and AI agents, all as TypeScript packages. Most CRMs give you a config panel. Twenty gives you a platform. Apps are how developers extend Twenty beyond what the UI offers — defining data models, server-side logic, UI components, and AI capabilities as code, then deploying them to one or more workspaces. ## Why apps exist Workflows cover no-code automation. But some things need code: a custom pricing engine, a proprietary enrichment pipeline, a compliance check that runs on every record update, a custom UI panel that pulls data from an internal tool. Apps let you build these as first-class extensions — not brittle scripts talking to an API from outside, but code that runs on the platform with full access to the type system, permission model, and UI. ## What an app can define An app is a TypeScript package that declares **entities** using the `twenty-sdk`: | Entity | What it does | | ---------------------- | --------------------------------------------------------------------------------------------- | | **Objects & Fields** | New data tables and fields on existing objects — same treatment as built-in ones | | **Logic Functions** | Server-side TypeScript triggered by HTTP routes, cron schedules, or database events | | **Front Components** | Sandboxed React components that render inside Twenty's UI (side panel, widgets, command menu) | | **Skills & Agents** | AI capabilities — reusable instructions and autonomous assistants | | **Views & Navigation** | Pre-configured list views and sidebar menu items | Everything is detected via AST analysis at build time — no config files, no registration boilerplate. Put a `export default defineObject(...)` in any `.ts` file and the SDK picks it up. ## How they run * **Logic functions** execute in isolated Node.js processes, sandboxed from the host. They access data through a typed API client scoped to the app's role permissions. * **Front components** run in Web Workers using Remote DOM — sandboxed from the main page but rendering native DOM elements (not iframes). * **Permissions** are enforced at the API level. An app only sees what its role allows. ## The developer experience You write your app as a TypeScript project on your machine. The CLI watches your source files and live-syncs them to a running Twenty server — edit a file, see the change in the UI within a second. The typed API client regenerates automatically when the schema changes. When you're ready, `yarn twenty deploy` pushes to a production server, or `yarn twenty publish` lists your app on npm and the Twenty marketplace. Three-phase walkthrough — scaffold, run a local server, sync your changes.