Arc is a high-performance time-series database capable of ingesting 2.4 million metrics per second, along with logs, traces, and events using a unified MessagePack columnar protocol. Currently in alpha release, it features a stable core with ongoing developments, including advanced SQL analytics via DuckDB, flexible storage options, and built-in token-based authentication, making it suitable for development and testing environments. The system is designed for high-throughput ingestion, low latency, and efficient data management, aiming to support observability across various telemetry types.