Diffblue

Diffblue is an Oxford University spinout that uses AI and reinforcement learning to automatically write Java unit tests, helping development teams improve test coverage and code quality with far less manual effort. Its flagship product, Diffblue Cover, autonomously generates and maintains unit tests at scale, targeting enterprise engineering teams working with large Java codebases. Founded in 2016 by Oxford researchers Daniel Kroening and Peter Schrammel, it has raised more than $46M in total, including a Series A led by Goldman Sachs and Oxford Sciences Innovation. Later investors include IP Group, AlbionVC and Parkwalk Advisors.