Show HN: ProjectFalcon – First Native Java at Protocol Implementation

[JohannaWeb]

We shipped the first native Java SDK for AT Protocol. No wrappers. No JavaScript dependencies. Hand-rolled ES256K verification using BouncyCastle with multicodec varint decoding and base58btc multibase.

The stack: Java 25, Spring Boot 4, Project Loom, Electron/React/TypeScript/Vite frontend, Kubernetes-ready microservices (falcon-core, falcon-gateway, falcon-web, siv-service, trust-service).

Core achievement: ES256K JWT verification that actually works. Full DID resolution. PDS write-through for sovereign identity. AT Protocol integration end-to-end.

Also shipped: FalconPub (Rust/Axum ActivityPub federation server), Falcon Bridge (cross-protocol translation layer), Juntos (native LGBT communities platform running live).

MIT licensed. ArXiv whitepaper on Sybil mitigation in federated networks.

github.com/JohannaWeb/ProjectFalcon