> For the complete documentation index, see [llms.txt](https://docs.fastn.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fastn.ai/tutorials/developer/deployment.md).

# Deployment

When you deploy the application you've embedded Fastn into, the main consideration is how environment variables and secrets bind on your deploy target. Getting this wrong is a common cause of a working local build that fails in production.

### Environment variables: runtime vs build time

Your embedded integration needs at least:

* `FASTN_API_KEY` — your `fsk_` API key
* `FASTN_END_ORG_ID` — the customer UUID

These must be available to the server-side function that generates embed tokens.

On some hosts, environment variables set in a CI pipeline are not automatically available to the deployed runtime. They bind at deploy time on the hosting target, not from the pipeline's own secrets. If the token function reads an undefined API key in production, token generation fails and the embed renders blank.

### Checklist for deploying

1. Set `FASTN_API_KEY` and `FASTN_END_ORG_ID` directly on the hosting target (not only in CI).
2. Use a `fsk_live_` key in production (and drop the `X-fastn-Test-Mode` header — see [Authentication & API Keys](/tutorials/developer/authentication-and-api-keys.md)).
3. Redeploy after changing environment variables, if your host binds them at deploy time.
4. Paste secret values raw — no surrounding quotes or brackets.
5. Confirm the token endpoint is reachable from your deployed backend.

### Verifying after deploy

Load the embedded page in production and confirm the widget renders and a token is being generated fresh on each load. If the iframe is blank, check that the environment variables are bound on the runtime, not just present in CI. See [Troubleshooting](/tutorials/developer/troubleshooting.md).


---

# 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.fastn.ai/tutorials/developer/deployment.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.