PubSweet

PubSweet is a free, open source framework for building state-of-the-art publishing platforms. PubSweet enables you to easily build a publishing platform tailored to your own needs. It is designed to be modular and flexible. PubSweet consists of a server and client that work together, and both can be modified and extended with components to add functionality to the system. There’s also a command-line tool that helps manage PubSweet apps.

PubSweet is being used for book publishing, academic journal production, and micropublication platforms by a growing number of established academic organizations including the University of California Press, eLife, Hindawi, California Digital Library and others.

Each of these organizations is building their custom platform using PubSweet, and contributing reusable open source components back to the community. By drawing on this growing library of components, PubSweet can be used to rapidly create custom publishing systems. If the existing components do not completely meet your needs, you can focus development on building new components to provide just the new functionality required.

If someone has built an entire publishing platform which you like (for example, Editoria or xPub), you can use it as-is, or replicate then extend it, using your own ideas and components with minimal effort.

Join the PubSweet community and help us build a common resource of open components for publishing by contributing components back.

https://pubsweet.coko.foundation/

Islandora

Islandora is an open-source software framework designed to help institutions and organizations and their audiences collaboratively manage, and discover digital assets using a best-practices framework.  Islandora was originally developed by the University of Prince Edward Island’s Robertson Library, but is now implemented and contributed to by an ever-growing international community.

Built on a base of Drupal, Fedora, and Solr, Islandora releases solution packs which empower users to work with data types (such as image, video, and pdf) and knowledge domains (such as Chemistry and the Digital Humanities). Solution packs also often provide integration with additional viewers, editors, and data processing applications.

Islandora operates under a GNU.

https://islandora.ca/

Invenio v3

Open Source framework for large-scale digital repositories.
Invenio is like a Swiss Army knife of battle-tested, safe and secure modules providing you will all the features you need to run a trusted digital repository.

https://invenio-software.org/