---
title: 'Deployment URL Checks'
description: 'Keep canonical, sitemap, and links pointing at the right origin across dev, preview, and production by setting URL and pathPrefix correctly and verifying the output.'
slug: 'deployment-url-checks'
type: 'article'
date: 2026-01-25T00:00:00.000Z
lang: 'en'
url: 'https://www.eleventy-baseline.dev/docs/feature-guide/deployment-url-checks/'
---

Keep your URLs correct across dev, preview, and production, so canonicals, sitemap entries, and links never leak `localhost` to the live site. The mechanics are mostly Eleventy and environment variables; this chapter is the small set of habits that keep them honest.

Three terms used below:

- **Canonical.** The `<link rel="canonical">` URL Baseline writes into every page's head.
- **pathPrefix.** Eleventy's option for deploying under a subpath (e.g. `/docs/`). Baseline's head and sitemap modules respect it.
- **Preview build.** A non-production deploy (a Netlify deploy preview, for instance) where the origin differs from production.

---

## What you will build

- A Baseline site that picks up the right origin for whichever environment it's in.
- Canonical and sitemap URLs pointing at the expected domain, preview included.

---

## Prerequisites

- Baseline installed and loaded.
- `package.json` with `"type": "module"` and the `dev`/`build` scripts:
  ```json
  {
  	"name": "simple-baseline-site",
  	"type": "module",
  	"scripts": {
  		"start": "rimraf dist/ && npx @11ty/eleventy --serve",
  		"build": "rimraf dist/ && cross-env ELEVENTY_ENV=production npx @11ty/eleventy"
  	}
  }
  ```

---

## 1) Set settings.url (and, separately, pathPrefix)

Use the `src/_data/settings.js` you already have from the previous tutorials. The field that matters for this chapter is `url`, the canonical origin:

```js
url: process.env.URL || 'http://localhost:8080/'; // override per env
```

If you're deploying under a subpath, set `pathPrefix` in `eleventy.config.js` (e.g. `/my-site/`) – it lives on the Eleventy config, not in `settings`. Baseline's head and sitemap output respect it without further wiring.

---

## 2) Set environment URLs (local and CI)

- Dev or local preview: create a local `.env` (don't commit it):
  ```txt
  ELEVENTY_ENV="development"
  URL="http://localhost:8080/"
  ```
- Production: set `URL` to the live origin (e.g. `https://www.example.com`) in your hosting or CI environment.
- Hosted previews (optional, e.g. Netlify): `URL` usually points to production while `DEPLOY_URL` and `DEPLOY_PRIME_URL` point to the preview. Baseline falls back to those when `URL` is missing. Skip if previews aren't part of your workflow.

Baseline loads `dotenv` for you, so `process.env.URL` works in both `_data/settings.js` and `eleventy.config.js`. The `HtmlBasePlugin` and the sitemap module both read it (and `pathPrefix`, if set).

---

## 3) Run with the right URL per environment

Dev: confirm your `.env` is loaded (e.g. `URL="http://localhost:8080/"`), then:

```bash
npm start
```

Production: set `URL` in hosting or CI to the live origin (not an inline shell export), then:

```bash
npm run build
```

Spot-check the rendered pages: canonical and sitemap entries should use the origin you expect.

---

## 4) Preview builds (optional)

- On Netlify, `DEPLOY_URL` and `DEPLOY_PRIME_URL` provide the preview origin, while `URL` stays set to the live site for production builds. Other hosts differ; set an equivalent preview URL env var for whichever staging environment you have.
- Confirm the rendered canonical and the sitemap root both match the preview domain.

---

## 5) Verify outputs

- View source on a rendered page. The `<link rel="canonical">` and every absolute link in the head should use the right origin. If `URL` is set in CI or production, none of them should say `localhost`.
- Inspect `dist/sitemap.xml` (and the per-language sitemaps if multilingual is on). URLs should start with the expected origin, plus `pathPrefix` if you've set one.

---

## 6) PathPrefix checklist (if applicable)

For the full subpath setup, see [[deploy-under-a-subpath | Deploy Under a Subpath]].

---

## Next steps

- Add a CI check that fails the build if `URL` is missing in production. One small step, lots of headaches saved.
- Pair with the [[multilingual-baseline-site | multilingual site tutorial]] to confirm hreflang URLs use the correct origin once multilingual is on.
- The [[config-export | config export reference]] covers `URL` and `pathPrefix` behaviour in full.