HammerDB is a leading open-source tool for database benchmarking, widely adopted across enterprise, cloud, and academic environments to evaluate transactional and analytic database performance. Originally developed as a personal open source project for testing the Oracle database on Linux, HammerDB has grown through a mission of accessibility, cross-platform support, and real-world relevance to become a trusted solution across the industry. This paper presents the story of HammerDB’s development, its architectural choices, major milestones, and evolution into a mature benchmarking suite with support for the most popular commercial and open source database systems. A key recent advancement is the release of HammerDB v5.0 in spring 2025, introducing a simplified installation with native packages for Linux and Windows, enhancing both performance and usability, furthering HammerDB’s goal of providing modern, portable and easy to use benchmarking tools. With its integration into the TPC-OSS subcommittee, HammerDB continues to bridge the gap between open source innovation and formal benchmarking standards. We also highlight ongoing performance collaborations with the database industry and outline future directions, including expanded workloads, cloud-native capabilities, and opportunities for community-driven contributions. This paper invites discussion on how open tools like HammerDB can shape the next era of collaborative database performance benchmarking.