https://github.com/sunaku/tork#readme

Tork runs your tests as they change, in parallel:

  1. Absorbs test execution overhead into a master process.

  2. Forks to inherit overhead and run test files in parallel.

  3. Avoids running unchanged tests inside changed test files.

## Version 19.2.1 (2013-02-08)

Patch:

  * GH-46: allow reassigning `$tork_*` variable values.  Thanks to Joe
    Escalante for reminding me to fix this issue.

  * GH-48: disable class caching at the ActiveSupport level for Devise.
    Thanks to Ryan Ahearn for fixing this issue and to Jonathan Cairns for
    reporting it.