https://buildkite.com https://buildkite.com has all those features, and very easy to work with. It's a hybrid hosted model -you supply your own workers (they p

https://buildkite.com https://buildkite.com has all those features, and very easy to work with. It's a hybrid hosted model -you supply your own workers (they provide a CFN template to make that part easy), everything else (e.g. web UI/API) is hosted