# Deploy Jekyll to thin.host

Build a Jekyll site to _site/ with the right baseurl and deploy it to thin.host. thin.host serves the static files and gives you a live URL right away. Your agent can do every step for you through the thin.host MCP server, or you can run one `curl` command.

## At a glance

| Step | Jekyll |
|---|---|
| Build command | `JEKYLL_ENV=production bundle exec jekyll build` |
| Folder to deploy | `_site/` |
| Preview build (served at `/s/my-site/`) | `JEKYLL_ENV=production bundle exec jekyll build --baseurl /s/my-site` |
| Deploy | `curl -F file=@site.zip -H "Authorization: Bearer $THINHOST_API_KEY" https://thin.host/v1/websites/archive` |
| Live URL | `https://thin.host/s/my-site/`, or your own domain |

## Before you start

- **Requires:** Ruby (with RubyGems, GCC and Make) and Bundler.
- **A thin.host account.** [Sign up](https://thin.host/signup), then create an API key under Settings (for `curl` and the local MCP server), or connect your agent with OAuth as shown in [Quickstart (MCP)](https://thin.host/docs/quickstart-mcp).

## Create a project (skip if you have one)

```bash
gem install jekyll bundler && jekyll new my-site
```

## Set the base path

Until a domain points at it, a thin.host site lives under a sub-path: `https://thin.host/s/<slug>/`. Jekyll prefixes links with baseurl when templates use the relative_url filter. Override it on the command line for the preview build; it is empty for a custom domain and never "/".

```yaml
# _config.yml
url: "https://www.example.com"
baseurl: ""
```

| Where readers will look | Build with |
|---|---|
| The preview URL `https://thin.host/s/my-site/` | `JEKYLL_ENV=production bundle exec jekyll build --baseurl /s/my-site` |
| A custom domain, or a free `<name>.thin.host` subdomain | `JEKYLL_ENV=production bundle exec jekyll build` (base path `/`) |

Pick the slug (`my-site` here) before you build the preview, and pass the same slug when you deploy.

## Build

```bash
JEKYLL_ENV=production bundle exec jekyll build
```

The finished site is in `_site/`. That folder is what you deploy.

## Deploy from your agent (MCP)

Connect thin.host to Claude Code, Claude Desktop, Cursor, VS Code, Windsurf, Codex or ChatGPT once ([setup for each client](https://thin.host/docs/quickstart-mcp)), then ask:

> Build this Jekyll project for thin.host with the slug my-site and publish the _site/ folder.

With the local server (`uvx thinhost-mcp`) the agent runs the build and calls `publish_website` with the absolute path of `_site/`; large builds are split across requests automatically. Later changes go out with `update_website` and `sync=true`, which also removes files the new build dropped.

The hosted connector (`https://thin.host/mcp`, used by claude.ai and ChatGPT) cannot read your disk. From a coding agent it uploads with the REST call below; otherwise it publishes from a public link to a zip or HTML file with `publish_website_from_url`.

## Deploy with curl

```bash
cd _site && zip -r ../site.zip . && cd -
curl -F file=@site.zip -F title="My Jekyll site" -F slug=my-site \
  -H "Authorization: Bearer $THINHOST_API_KEY" \
  https://thin.host/v1/websites/archive
```

The JSON response includes `url`, the live address (`https://thin.host/s/my-site/`). To redeploy, upload the new zip to the site's archive endpoint; pages and assets missing from it are removed:

```bash
curl -F file=@site.zip \
  -H "Authorization: Bearer $THINHOST_API_KEY" \
  https://thin.host/v1/websites/my-site/archive
```

A single upload can be up to 30 MB. See the [REST API reference](https://thin.host/docs/api) for every field.

## Add a custom domain

1. Open the site in the [dashboard](https://thin.host/dashboard) and add your hostname under **Custom Domains**, for example `www.example.com`. A `<name>.thin.host` subdomain is free and works immediately.
2. Create the DNS record the dashboard shows: a `CNAME` pointing at `cname.thin.host`. TLS is issued automatically once DNS resolves.
3. Rebuild with the base path `/` (`JEKYLL_ENV=production bundle exec jekyll build`) and redeploy.

Pages on a custom domain get a canonical tag, a generated `robots.txt` and a `sitemap.xml`.

## Jekyll notes

- Write internal links as {{ '/about/' | relative_url }}; hard-coded /paths ignore baseurl.
- GitHub Pages builds Jekyll for you; on thin.host you upload the built _site/ folder.

## FAQ

**Can I keep my GitHub Pages Jekyll site and also deploy it to thin.host?**

Yes. Build locally or in CI with bundle exec jekyll build and upload _site/. GitHub Pages' plugin allowlist does not apply, so any plugin your Gemfile installs works.

**Why does the preview URL load without styles or scripts?**

The site is served under /s/<slug>/ until a custom domain points at it, so a build that references /assets/... asks the thin.host root for files that live under the sub-path. Build with the base path set to /s/<slug>/ for the preview, or map a domain (a free <name>.thin.host subdomain works) and build with base /.

**How do I redeploy?**

Rebuild, zip the output folder again and POST it to /v1/websites/<slug>/archive, or ask your agent to run update_website with sync=true. Sync removes files the new build no longer contains, so old hashed bundles do not pile up.

**How large can a site be?**

A single archive upload can be up to 30 MB. The local MCP server (uvx thinhost-mcp) reads the build folder directly and splits large sites across requests, up to 150 MB.

## Sources

Commands and options checked against the official Jekyll docs on 2026-10-14:

- [Jekyll: Deployment](https://jekyllrb.com/docs/step-by-step/10-deployment/)
- [Jekyll: Configuration options (baseurl)](https://jekyllrb.com/docs/configuration/options/)
- [Jekyll: Liquid filters (relative_url)](https://jekyllrb.com/docs/liquid/filters/)

Other frameworks: [all deploy guides](https://thin.host/guides). Coming from another host? [Compare thin.host](https://thin.host/compare).

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Canonical page: https://thin.host/guides/deploy-jekyll