Getting Started
Lean CMS is installed directly into your Rails app. There is no separate admin panel to deploy — the CMS lives alongside your application code, namespaced under LeanCms::.
What Lean CMS is
A CMS built for Rails developers who are building marketing sites for clients:
- Fixed pages, editable content — your page structure is defined in code and YAML; editors can change text, images, and rich content but not add or remove pages
- Blog and portfolio — editors can create, draft, and publish posts
- In-context editing — no separate “dashboard” for content editing; editors click Edit directly on the live page
- Your design, your templates — Lean CMS provides helpers to pull content into ERB; it never touches your layout or styles
What Lean CMS is not
- A page builder (pages are defined by developers, not editors)
- A theme system (you write your own Tailwind CSS / HTML)
- A headless CMS (it’s server-rendered Rails, not an API)
Prerequisites
- Ruby 3.2+
- Rails 8.0+
- SQLite3
Lean CMS is designed specifically for the SQLite + Rails 8 stack. See SQLite Production for why this is the right choice for marketing sites.