How can I install something on Travis CI without a timeout?

The default timeout per command on Travis is 10 minutes and when you use the function travis_wait only, the timeout is 20 minutes. If your build need wait more than 20 minutes, you can pass a number of minutes to function travis_wait, exemple:

$ travis_wait 30 pip install scipy

This is a function undocumented in Travis, but it is suggested by Hiro Asari from Travis on github issue.

The solution is straightforward. Just prefix the installation command with travis_wait. More details are available at https://docs.travis-ci.com/user/common-build-problems.