OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)

Open source alternative to Auth0 / Firebase Auth / AWS Cognito

Efficient reliable UDP unicast, UDP multicast, and IPC message transport

Apache HBase

H2 is an embeddable RDBMS written in Java.

Dremio - the missing link in modern data

DJI Mobile SDK for Android: http://developer.dji.com/mobile-sdk/

An open source data gateway

React Native TCP socket API for Android, iOS & macOS with SSL/TLS support.

IPFS and libp2p on Mobile, with Gomobile

"Fast as internal ring buffer" Logback/Log4J2 appender using SQLite with zstandard dictionary compression and rollover.

FoundationDB storage adapter for JanusGraph

DBOS file system using Voltdb