If you are using GitHub repositories in Composer, you might notice that it takes a long time to run composer update . This is because Composer uses the GitHub API in an effort to improve performance. Unfortunately, GitHub API is very slow and you might need hundreds of calls for a single repo, depending on the number of tags. You can disable this behaviour by specifying the undocumented no-api flag in Composer. In composer.json , add it like this:

{ "type": "vcs", "url": "git@github.com:user/repo.git", "no-api" : true }

This will make Composer check out the repository via Git instead, usually improving composer update times by 2-3x.

Discussion on Reddit with more info on the technical details

More information regarding the no-api flag