Tast is an integration-testing system for Chrome OS. Its focus is on maintainability, speed, and ease of interpreting and reproducing test results. It supports building, deploying, and running tests. It doesn't implement other functionality like managing labs of devices used for testing, scheduling tests, or storing test results.
The overview is a good starting point.
This repository is organized in accordance with the Go in Chromium OS suggestions.
Tests are located in the tast-tests repository.
For more details, see the docs subdirectory.