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Lavalite - PHP CMS built with Laravel and Bootstrap.
Bludit - Bludit is a web application to build your own website or blog in seconds, it's completely free and open source. Markdown support.
DEV.to - Where software engineers connect, build their resumes, and grow.
HTMLy - HTMLy is an open source databaseless blogging platform. A Flat-File Blog and Flat-File CMS written in PHP prioritizes simplicity and speed.
Gila CMS - An on-in-one solution for the digital business