Running three hours of Ruby tests in under three minutes (135 words)

Recently the very cool hard working developers working on Stripe released a post about how they modified their build/test pipeline to reduce their test suite runtime from 3 hours to about 3 minutes.

The article is very much worth reading, as is the discussions that have come around it including those on Hacker News.

A few key takeaways,

The above ensures that the tests are generally more reliable and you avoid having to write your own teardown code which restores state, both in memory for the forks and on disk using Docker.