Most AI memory tools either score badly or cost $249/mo. So I built MemoryOS — an open-source, self-hosted memory layer for AI agents. Benchmarks (LongMemEval-s, ICLR 2025): • HydraDB - 90.79%, <200ms - $249/mo • Supermemory - 85.4%, <300ms • MemoryOS - 86.2%, 78ms - free ; open source Features: * Temporal knowledge graph with point-in-time memory * Hybrid retrieval: vector + BM25 + graph traversal * Human-inspired memory decay * 9ms/msg ingest pipeline * Fully local retrieval hot path