Cucumber is an open-source test framework for behaviour-driven development (BDD). Teams write automated acceptance tests in plain language, in the Gherkin format, so that non-programmers can read them too. According to the project site, Cucumber supports many platforms, including Java, JavaScript, Ruby and .NET. It is a library that runs locally or in a CI pipeline; the project has no central cloud service. Its code, such as Cucumber-JVM, is released under the MIT licence.
Cucumber began as a Ruby project and was acquired by SmartBear in 2019. In December 2024 SmartBear transferred the name, trademarks and the cucumber.io domain to the US-based Open Source Collective, a non-profit that holds the project on behalf of the community. Because the software runs wherever you install it and sends no customer data to a vendor, jurisdictional exposure is limited to the stewarding organisation and the project's dependencies. SmartBear also offers commercial products around Cucumber, which are outside this overview.