Firebird

Firebird is a relational database descended from the InterBase source code that Inprise released on 25 July 2000, with roots that were deployed as far back as 1981. The Firebird Project develops it with volunteers, and the Firebird Foundation supports its funding. The software is licensed under the InterBase Public License, known as the IDPL, according to the project's about page. It can run as a server or in embedded form. There is no commercial edition of the database, although commercial support is available from third parties. The latest release is 5.0.4, published on 17 April 2026, and the project maintains versions 5.0, 4.0 and 3.0 side by side. This gives teams on older deployments a supported route without an immediate major upgrade, although they should still plan to move to the current line over time. Pricing is not published, because the database is free to use. Buyers should read the licence text for themselves, because the IDPL is a specific open source licence with its own conditions. Anyone redistributing the software inside a product should check how those conditions apply to their case.