Alternatives to Wagtail

Django CMS is a free and open-source content management system build on the Python web framework Django. With Django CMS, you can create your own website or blog in a matter of minutes which is easy to maintain far into the future. If you are a developer utilizing the Django framework you can integrate Django CMS into an exiting Django application and take advantage of it's publishing and editing features.

Ghost is a free and open-source headless CMS and blogging platform developed by Ghost Foundation. With Ghost you can manage content in style, the user experience provided by the software is intuitive and encourages writing. Ghost is written in JavaScript for the Node.js platform and is released under the MIT license.

CMS Made Simple is a free and open-source content management system that offers an easy to use interface for end users, while maintaining a powerful backend for developers. CMS Made Simple is written in PHP and got an extensive API and custom modules. The CMS also utilize the Smarty templating engine that can be used to customize sites with HTML, CSS and PHP.

ButterCMS is a commercial headless content management system and content API. With ButterCMS you can quickly setup your very own headless CMS that supports In-browser editing. Where you can quickly find and filter your images and files, update and schedule content and serve you assets over a content delivery network.

Netlify CMS is a static site generator that is based on client-side JavaScript with a reusable APIs and prebuilt Markup. Simply pull in Netlify CMS to /admin of you site and you have an SPA (Single Page Application) admin panel that can edit content stored in a Git repository. Serving applications like this, the JAMstack way, improves performance, lowers cost of scaling and provides for a better development experience.

A hybrid content management system that includes classic CMS and Headless CMS features. With dotCMS content managers can create content that fuels the brand experience. The API-first approach provided by the headless part of dotCMS allows developers to build extremely fast front-ends with popular third-party front-end framework and deliver content optimally. The content management system allows content creators to build engaging and memorable content that can be reused across sites.

An open-source tool for managing content across all your omni-channel digital experiences. Directus is free and open-source headless CMS written in PHP, that takes a data first approach. Developers and content creators use Directus to manage content and generate a powerful API that can be used by any frontend technology. Directus can be self-hosted and is absolutely free.

Strapi is a free and open source headless CMS developed with JavaScript for Node.js. The software makes it really simple to generate REST and GraphQL APIs. Simply create your database schema and relationships in the Strapi admin panel UI, and Strapi will auto-generate API endpoints to represent the data structures provided. Strapi comes packed with features you come to expect from normal CMS's such as authentication, authorization, content management and a media library. The software can be used for free and can be self-hosted on any server and platform. Extra enterpise functionallity is currently being developed, and will be sold at cost.

With Contentstack, content and marketing teams are able to publish content with a much higher frequency than ever before. Contentstack brings business and technology teams closer together by providing a personalized, omnichannel experience with a visual editor alongside content scheduling and publishing management tools.

WordPress powers roughly 30% of all web pages online. It's a free and open source CMS designed and developed for self-hosted publishing by Automattic, Inc. The software is written in PHP and utilize either MySQL or MariaDB as a database, and is compatible with most web hosts. Wordpress includes a plugin architecture and a templating system that can be used to extend and customize your website. These are commonly known as WordPress plugins and WordPress themes and make up a whole open source and commercial eco-system where anyone is free to create products for the platform. 

The Mura CMS platform makes it easier & faster to build and update websites. The content management system was created to free content managers from distraction of multiple tools, the worry of steep learning curves, and a clear need to tell the right story, to the right audience, at the right time. Mura is loved by content managers, content contributors, marketers and developers alike.

With Airsite you can create landing pages for yourself or your business, on your mobile phone. Airsite can be used on your Android or iOS devices and allow your to build your next page without any programming or web design skills.

Joomla is a free and open-source content management system written in PHP. The CMS is built entirely by volunteers from all over the world and has a strong community that provide educational resources, and extensions. 

Grav is a modern free and open source flat-file content management system. With Grav, you can publish content and build sites in a fast, flexible and simple manner with the file-based web platform. Grav requires zero installation and is just an zip archive that can be extracted to start using the CMS. Grave also comes with a powerful package management system that allow you to extend the feature set of Grav CMS. With the package management system you can install and upgrade themes and plugins written specifically for Grav. The software is written in PHP and released fully free and open-source under the MIT License.

Ponzu is a powerful, free and open-source HTTP server framework and CMS. It provides automatic, free, and secure HTTP/2 over TLS with Let's Encrypt, a useful CMS and scaffolding to generate content editors, and a fast HTTP API on which to build modern applications.

A free and open-source headless CMS built with Node.js and MongoDB.

Tina is an open-source site editing toolkit and headless CMS for React-based sites like Gatsby & Next.js

Backdrop is a full-featured content management system written in PHP. The Backdrop CMS allows non-technical users to manage a wide variety of content. It can be used to create all kinds of websites including blogs, image galleries, social networks, intranets, and more.

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Anchor is a super-simple, lightweight blog system written in PHP. Compressed, Anchor CMS weighs in at just under 250kb making it an extremely light weight content management system. With Anchor CMS, you can manage content in HTML or Markdown, depending on which you prefer. The content management is fully free and open-source and released under the GPL-3.0 License.