Open source alternative to Auth0 / Firebase Auth / AWS Cognito

BookLore: A self-hosted, multi-user digital library with smart shelves, auto metadata, Kobo & KOReader sync, BookDrop imports, OPDS support, and a built-in reader for EPUB, PDF, and comics.

Gnirehtet provides reverse tethering for Android

Open Location Code is a library to generate short codes, called "plus codes", that can be used as digital addresses where street addresses don't exist.

[Unmaintained] Open source two-factor authentication for Android

A system for distributing and managing secrets

Teletraan is Pinterest's deploy system.

Syncany is a cloud storage and filesharing application with a focus on security and abstraction of storage.

MySQL performance monitoring and analysis.

The Geneva electronic vote system, version 1.