VuFind - VuFind is a library resource portal designed and developed for libraries by libraries.
Invenio - Invenio is a free, open-source software to run a digital library or document repository on the web.
Preplar - A simple assignment organisation app built by a 14 year old
Greenstone Digital Library - Greenstone is a suite of software tools for building and distributing digital library collections...
E-Prints - EPrints supports research papers, theses, teaching materials, arts and more.
Koha - Koha is the first free and open source software library automation package (ILS).