> For the complete documentation index, see [llms.txt](https://docs.n8n.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.n8n.io/build/code-in-n8n.md).

# Code in n8n

n8n is a low-code tool. This means you can do a lot without code, then add code when needed.

## Code in your workflows <a href="#code-in-your-workflows" id="code-in-your-workflows"></a>

There are two places in your workflows where you can use code:

* **Expressions**

  Use expressions[^1] to transform [data](/build/work-with-data/overview.md) in your nodes. You can use JavaScript in expressions, as well as n8n's [Built-in methods and variables](/build/code-in-n8n/use-built-in-shortcuts.md).

  [→ Expressions](/build/work-with-data/expressions-versus-data-nodes.md)
* **Code node**

  Use the Code node to add JavaScript or Python to your workflow.

  [→ Code node](/build/code-in-n8n/using-the-code-node.md)

## Other technical resources <a href="#other-technical-resources" id="other-technical-resources"></a>

These are features that are relevant to technical users.

### Technical nodes <a href="#technical-nodes" id="technical-nodes"></a>

n8n provides core nodes, which simplify adding key functionality such as API requests, webhooks, scheduling, and file handling.

* **Write a backend**

  The [HTTP Request](/integrations/builtin/core-nodes/n8n-nodes-base.httprequest.md), [Webhook](/integrations/builtin/core-nodes/n8n-nodes-base.webhook.md), and [Code](/build/code-in-n8n/using-the-code-node.md) nodes help you make API calls, respond to webhooks, and write any JavaScript in your workflow.

  Use this do things like [Create an API endpoint](https://n8n.io/workflows/1750-creating-an-api-endpoint/).

  [→ Core nodes](/integrations/builtin/core-nodes.md)
* **Represent complex logic**

  You can build complex flows, using nodes like [If](/integrations/builtin/core-nodes/n8n-nodes-base.if.md), [Switch](/integrations/builtin/core-nodes/n8n-nodes-base.switch.md), and [Merge](/integrations/builtin/core-nodes/n8n-nodes-base.merge.md) nodes.

  [→ Flow logic](/build/flow-logic.md)

### Other developer resources <a href="#other-developer-resources" id="other-developer-resources"></a>

* **The n8n API**

  n8n provides an API, where you can programmatically perform many of the same tasks as you can in the GUI. There's an [n8n API node](/integrations/builtin/core-nodes/n8n-nodes-base.n8n.md) to access the API in your workflows.

  [→ API](/connect/n8n-api.md)
* **Self-host**

  You can self-host n8n. This keeps your data on your own infrastructure.

  [→ Hosting](/deploy/host-n8n.md)
* **Build your own nodes**

  You can build custom nodes, install them on your n8n instance, and publish them to [npm](https://www.npmjs.com/).

  [→ Creating nodes](/connect/create-nodes/overview.md)

[^1]: In n8n, expressions allow you to populate node parameters dynamically by executing JavaScript code. Instead of providing a static value, you can use the n8n expression syntax to define the value using data from previous nodes, other workflows, or your n8n environment.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.n8n.io/build/code-in-n8n.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.