PullApprove lets teams build automated code review workflows. Use custom rules to decide exactly who needs to review which pull requests, and PullApprove will send review requests and track approval requirements.
This repo contains the open-sourced components, but certain key pieces are still proprietary.
We run a hosted service and GitHub App that you can quickly install and use. We also have a self-hosted PullApprove Enterprise for large teams using GitHub Enterprise.