K3s is a fully compliant production-grade Kubernetes distribution with the following changes:

• Legacy, alpha, non-default features are removed. Many of these features are not available in most Kubernetes clusters already.
• Removed in-tree plugins (cloud providers and storage plugins) which can be replaced with out-of-tree add-ons.
• Added sqlite3 as the default storage mechanism. etcd3 is still available, but not the default.
• Wrapped in a simple launcher that handles a lot of the complexity of TLS and options.

Rancher is also doing an online meet-up and demo of K3s on March 13, 2019.