Oracle trademark dispute. Overwhelming contributor vote. Nearly every plugin developer followed. Hudson died at Eclipse.
Hudson/Jenkins is a Java-based continuous integration and continuous delivery (CI/CD) server. It automates the building, testing, and deployment of software projects, with an extensible plugin architecture that allows integration with virtually every development tool. It pioneered the concept of 'pipeline as code' for build automation.
Hudson was born in 2004 as a side project by Kohsuke Kawaguchi, a developer at Sun Microsystems who was tired of breaking builds. It grew into the most popular continuous integration server in the Java world, with a thriving ecosystem of plugins and an active community of contributors. Then Oracle bought Sun in 2010, and everything went sideways.
The trouble started when Oracle began asserting control over the Hudson trademark, applying for a registered trademark in December 2010 without consulting the community. The Hudson developers tried to negotiate — they offered to place the trademark under a neutral third party like the Software Freedom Conservancy — but Oracle wasn't interested in sharing control. The community saw this as Oracle trying to leverage trademark ownership to control the project's direction and potentially commercialize it.
On January 11, 2011, Kawaguchi proposed renaming the project from Hudson to Jenkins. The community vote was devastating for Oracle: 214 in favor, 14 against. On January 29, the rename was approved, and the Jenkins project was born. Oracle responded by declaring that Hudson would continue under their stewardship and that Jenkins was 'the fork' — a characterization the Jenkins community vehemently rejected, since they represented the overwhelming majority of contributors.
The developer exodus was swift and nearly total. Approximately 85% of developers immediately migrated to Jenkins. Of the top 25 plugins, 21 moved to Jenkins; the other four simply had no active commits. Oracle tried to salvage Hudson by donating it to the Eclipse Foundation in May 2011, but it was too late — the community had spoken with their feet.
Hudson limped along at Eclipse for several years before being declared obsolete in February 2017. Jenkins, meanwhile, became the dominant CI/CD platform worldwide, spawning companies like CloudBees and serving as the backbone of software delivery pipelines across the industry.
Kohsuke Kawaguchi creates Hudson at Sun Microsystems
Oracle acquires Sun Microsystems
Oracle applies for Hudson trademark without community consultation
Kawaguchi proposes rename from Hudson to Jenkins
Community vote: 214-14 in favor of rename to Jenkins
Oracle declares Hudson will continue; claims Jenkins is 'the fork'
Oracle donates Hudson to Eclipse Foundation
Hudson declared obsolete at Eclipse Foundation
“Bye bye Hudson, Hello Jenkins.”
Jenkins became the undisputed king of CI/CD, with tens of thousands of installations worldwide and over 1,800 plugins. It essentially defined the modern continuous integration workflow and spawned an entire ecosystem of companies, tools, and practices. CloudBees built a venture-backed business around Jenkins, and the project influenced every CI/CD tool that came after it.
The fork also became Oracle's most embarrassing open-source moment (in a field of stiff competition). It demonstrated that trademarks are meaningless when the entire community walks out the door — you can own the name, but you can't own the people, the plugins, or the momentum.