HTMLy is an open source Databaseless Blogging Platform or Flat-File Blog prioritizes simplicity and speed written in PHP. HTMLy can be referred to as Flat-File CMS either since it will also manage your content. HTMLy uses a unique algorithm to find or list any content based on date, type, category, tag, or author, and it's performance remain fast even if we have ten thousand of blog posts and hundreds of tags.
As a flat-file CMS, With 512MB of RAM or even less, it should can handle more than 20K posts without any issues.
Features:
<ul dir="auto">
<li>Admin Panel</li>
<li>Markdown editor with live preview and image upload</li>
<li>Categorization with category and tags (multiple tagging support)</li>
<li>Static Pages (e.g. Contact Page, About Page)</li>
<li>Meta canonical, description, and rich snippets for SEO</li>
<li>Pagination</li>
<li>Author Page</li>
<li>Multi author support</li>
<li>Social Links</li>
<li>Disqus Comments (optional)</li>
<li>Facebook Comments (optional)</li>
<li>Google Analytics</li>
<li>Built-in Search</li>
<li>Related Posts</li>
<li>Per Post Navigation (previous and next post)</li>
<li>Body class for easy theming</li>
<li>Breadcrumb</li>
<li>Archive page (by year, year-month, or year-month-day)</li>
<li>JSON API</li>
<li>OPML</li>
<li>RSS Feed</li>
<li>RSS 2.0 Importer (basic)</li>
<li>Sitemap.xml</li>
<li>Archive and Tag Cloud Widget</li>
<li>SEO Friendly URLs</li>
<li>Teaser thumbnail for images and Youtube videos</li>
<li>Responsive Design</li>
<li>User Roles</li>
<li>Online Backup</li>
<li>File Caching</li>
<li>Online Update</li>
<li>Post Draft</li>
<li>i18n</li>
<li>Menu builder</li>
</ul>

HTMLy is an open source Databaseless Blogging Platform or Flat-File Blog prioritizes simplicity and speed written in PHP. HTMLy can be referred to as Flat-File CMS either since it will also manage your content.

HTMLy  - Simple and fast databaseless PHP blogging platform, and Flat-File CMS 

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Tina is an open-source site editing toolkit for React-based frameworks (Gatsby & Next.js). Manage content on your own site, not another platform. Import Tina directly into your components to expose an editing interface for controlling and updating layers of your content mesh. You define the content model and editing powers specific to your site.

Tina - Site editing toolkit for modern React-based sites (Gatsby and Next.js)

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Ghost is a powerful app for new-media creators to publish, share, and grow a business around their content. It comes with modern tools to build a website, publish content, send newsletters & offer paid subscriptions to members. It powers serious blogs, magazines and journalism from DuckDuckGo, Tinder, OpenAI, Sky News and many more.

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The Sanity Studio is an open-source CMS built with React.js. It offers rapid configuration and free form customization. It ships as an open-source single page application. Install plugins from npm or build your own. Integrate Sanity in your applications. It provides instant updates, describe content models, validations, and UI structures in JavaScript and see them instantly hot-reload in the next window.

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Statamic - Flat-first, Laravel + Git powered CMS designed for building beautiful, easy to manage websites


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Projects

HTMLy - Simple and fast databaseless PHP blogging platform, and Flat-File CMS