Shipper is a set of controllers for orchestrating rollouts to one or many Kubernetes clusters. It uses Helm charts and CRDs to specify what should be deployed, and how it should be rolled out. It provides functionality on top of core Kubernetes Deployment objects by automating blue/green or canary rollout patterns, including traffic shifting between versions.
Here's a video demo of Shipper from the SIG Apps community call last June. Our object definitions have changed a little bit since then, but this is still a good way to get a general idea of what problem Shipper is solving and how it looks in action.
Shipper is in active use inside Booking.com, but we have a ways to go before it is a consumable open source product. If you're reading this note on HEAD, it means we're still working on our first round of docs, installation guides, communication channels, and so on. Please bear with us while we make the transition from internal to external :)