# Build with Nile

Build your backend around services and actions. A service groups a business domain, such as billing. An action defines one operation with a validation schema and a handler. Your team and coding agents can follow the same structure as you add features.

## Start with one operation [#start-with-one-operation]

Create the [starter project](/guide/start/getting-started), call its Tasks service and add your first action. Keep using its domain structure as you add operations.

| Your next task | Guide |
| --- | --- |
| See every built-in feature with an example | [Features](/guide/features) |
| Build a complete feature step by step | [Examples](/guide/examples) |
| Find a home for growing business logic | [Application structure](/guide/start/application-structure) |
| Validate input and return useful failures | [Actions](/guide/basics/actions) and [errors and Results](/guide/basics/errors-and-results) |
| Share resources and access policies | [Context](/guide/basics/context) and [authentication](/guide/basics/auth) |
| Connect your frontend | [Frontend client](/guide/basics/client) |
| Add live updates | [Sockets and typed messages](/guide/reference/realtime) |
| Schedule work and control concurrency | [Production operations](/guide/reference/operations) |
| Trace a failed operation | [Logging](/guide/internals/logging) |
| Use the handler context, hooks and execution options | [Advanced](/guide/advanced) |

## Keep the business logic yours [#keep-the-business-logic-yours]

Use ordinary TypeScript functions for domain rules and your chosen library for data access. Nile Js supplies the shared execution patterns: validation, Results, hooks, context and logging. Register your services explicitly so someone joining the project can see which operations it exposes.

Choose [Bun native or the Hono adapter](/guide/start/runtime-adapters) for HTTP. Call the same action through `server.invoke` within your backend, or expose it over Socket.IO when your application needs a connected client.

## Work with a coding assistant [#work-with-a-coding-assistant]

Give your assistant the [Nile Js skill](/guide/agents/skill) and the [documentation index](/guide/reference/llms-txt), and expose selected runtime schemas through [discovery](/guide/basics/discovery-and-agents). Documentation explains Nile Js conventions; your application's schemas describe its operations and input shapes. [Build with AI agents](/guide/agents) walks through the setup.