QuestDB

QuestDB is an open-source, high-performance SQL time-series database designed for ultra-low latency and demanding workloads.

Founded in 2019 in London, the company was established by Vlad Ilyushchenko, Tancrede Collard, and Nicolas Hourcard. QuestDB has raised over $18 million in venture capital and has grown to approximately 29 employees, with offices in London and New York. The core product is a columnar, SQL-based time-series database optimized for speed and efficiency. It features a unique architecture that maximizes performance without relying on powerful hardware. QuestDB supports millisecond queries and high ingestion throughput, making it suitable for applications in capital markets, crypto, space exploration, energy, and robotics. The database is available for self-hosted deployment or in the cloud, ensuring data portability and compatibility with open formats. QuestDB aims to refine its database for production use cases while fostering an active community.