Google Code was one of the first places for developers to share and collaborate on different projects. It came out in 2006 and hosted open source projects, Wiki pages, and Git, Mercurial, and SVN repositories, among other tools.
In March 2015, Google announced on their Open Source Blog that they were shutting down the Google Code service. They admitted to having lost to the competition.
When Google Code first appeared in 2006, developers had very few options to host their projects. Ten years later, there were more and better alternatives to Google Code, such as GitHub, Bitbucket, and SourceForge, and many developers preferred them. Even Google moved more than 1,000 of their projects to GitHub.
Furthermore, Google Code was left with many spam projects and abuse management tools, and Google felt it wasn’t worth maintaining the service. They informed users the existing projects would be read-only from August 2015, and the service would be closed on January 25, 2016.
Google provided several tools for migrating projects to the other hosting platforms and offered developers further support for saving their work. There was a suggestion from users that projects that were no longer maintained, since their owners were AWOL or dead, should still be archived in a read-only format. These can be found on the Google Code Archive.