Kirby for publishers: a flat-file CMS with a one-off licence

What is Kirby?

Kirby is a PHP content management system that stores content as folders and text files instead of in a database. Its documentation says that, since it is a flat-file CMS, all content lives in the content folder and each folder is a page with its own URL. Editors use a web panel, and developers define what the panel shows with configuration files called blueprints.

The source code is public, but the licence page is blunt that Kirby is not free software. Public sites need a paid licence. For what that means in practice, see our licensing guide.

Who is Kirby best for?

Kirby fits small publications, magazines and portfolio-style news projects with a developer or agency who wants full control of templates and a simple hosting setup. Because there is no database, a site can run on ordinary PHP hosting and be copied or backed up as files.

It is a weaker fit for a large newsroom that needs complex approval chains, a big plugin market or hosted support, and for any team without a PHP developer. If you want a free licence, look at the open-source profiles in the CMS directory.

Think of a small independent title with a designer-developer who wants a distinctive layout and a handful of editors who only need to write and publish. Kirby’s panel can be shaped to show editors exactly the fields they need, and the licence is paid once per site. For a publisher running a dozen titles, per-site licences and per-site file installs add up in cost and in maintenance.

Ask early who will handle updates, backups and the PHP version, because there is no vendor-run dashboard doing it for you.

Editorial workflow

Kirby has three page states: draft, listed and unlisted. Drafts are visible only to logged-in users, while listed and unlisted pages are reachable by URL and only listed pages appear in navigation. The documentation says these states can be customised to build workflows such as draft, unreviewed and published.

Permissions are defined in blueprints: in a user blueprint for each role, or in page, file or site blueprints for finer rules. The admin role always has full rights. Roles such as editor or manager are examples you define yourself, not built-in presets according to the page we read.

We did not find revision history, content locking or scheduling described in the pages we opened, so confirm those against the current documentation if your desk depends on them.

SEO, structured data and feeds

The Kirby cookbook gives a recipe for a sitemap and refers to community plugins for more complex needs; the core does not provide one. Meta titles, descriptions, structured data and RSS feeds are, in practice, template work. We could not verify a built-in feed or redirect manager.

That is not unusual for a developer-first system, but it means the SEO quality of the site equals the quality of its build. Follow Google’s documentation for structured data and news publishers, and check any plugin’s licence and maintenance.

Media, multilingual and performance

Multi-language is built in. The documentation covers translating content, translating URLs, custom language variables, switching languages in the frontend and right-to-left languages. This is a stronger starting point than systems where translation needs an add-on, though the front-end work is still yours.

The pages we opened did not cover image handling or caching in detail, so we make no claims on those. Flat files keep the stack small, which helps on modest hosting. See the feature checklist.

Hosting and requirements

The quickstart lists PHP 8.2, 8.3, 8.4 (recommended) and 8.5, and says Kirby needs a standard set of PHP extensions. Apache works out of the box. For nginx and Caddy, the documentation provides configuration examples. No database requirement is listed.

That makes a Kirby install light to host, but it also means content is files on your server: backups, deployments and concurrent edits are your responsibility. The self-hosted guide covers the operational side.

Extending Kirby

Kirby has a plugin directory, and the cookbook points to community plugins for sitemaps. We have not verified how many plugins exist, who maintains them or how quickly they follow new Kirby releases, so we give no count.

The developer defines the editing experience through blueprints and builds the front end in PHP templates. We have not reviewed Kirby’s API documentation, so we make no claims about decoupled use; see the headless section for general guidance.

What does Kirby cost?

Per the buy page on 2026-10-10: Basic is EUR 99 per site for those with under EUR 1 million in annual revenue or funding, and Enterprise is EUR 349 per site with no revenue limit. Prices exclude VAT. It is a one-time purchase with no subscription.

The licence includes three years of feature updates. After that you may keep using the latest version released in the three years, or buy more update years at EUR 59 (Basic) or EUR 249 (Enterprise). Each licence covers one website and must be activated to its domain. Development installations are free. Add hosting and developer time; our cost guide shows the other lines.

Compared with a free open-source CMS, the licence is a small fixed cost that buys a defined product and a three-year update window. Compared with an agency day rate it is negligible. The cost that matters is the build: blueprints, templates, a sitemap and a feed are all developer tasks, so a quote that covers them is worth more than the licence figure.

Where does Kirby fall short?

• Not free software. The code is visible but a public site requires a paid licence per website.
• Thin newsroom workflow. The pages we read describe three page states and role blueprints, not multi-stage approval or revision history.
• Core omissions. No built-in sitemap; feeds and redirects need development or plugins.
• Files on a server. No database means simple hosting but your own backup and deployment discipline.
• Revenue threshold. Basic applies under EUR 1 million revenue or funding; larger organisations pay the Enterprise price.

The verdict for publishers

Kirby is a good fit for small, design-led publications with a developer, where a simple stack and a one-off licence matter more than a plugin marketplace. Built-in multi-language support is a genuine advantage.

If you need strong editorial controls out of the box or a free licence, other systems do more. This profile is drawn from the vendor’s documentation, not a test install; see how we test.