Keycloak 24’s default configuration chokes on 2k concurrent users—but with PostgreSQL 17 and Redis 8.0, we pushed it to 10k active sessions with 89ms p99 latency, zero dropped requests, and 40% lower infrastructure costs than the legacy JDBC-only setup. 📡 Hacker News Top Stories Right Now Ghostty is leaving GitHub (1994 points) Before GitHub (328 points) How ChatGPT serves ads (211 points) Bugs Rust won't catch (35 points) Show HN: Auto-Architecture: Karpathy's Loop, pointed at a CPU (41 points) Key Insights Keycloak 24’s new distributed session store reduces database roundtrips by 72% compared to Keycloak 21’s JDBC session implementation PostgreSQL 17’s native JSONB indexing cuts user attribute lookup latency from 210ms to 14ms at 10k user scale Redis 8.0’s hash field expiration lowers session storage costs by 63% versus Redis 6.2’s full-key TTL approach By 2026, 80% of Keycloak production deployments will use a hybrid RDBMS + Redis architecture for auth workloads Architectural Overview Before diving into…