That way, everyone has an identical dev environment and we don't depend on any particular IDE (want to use Emacs? sure). No setup steps, just running one script to create a new namespace with all applications running inside. Broke it, messed up an upgrade? Just destroy and redeploy.
We hacked Arcanist[1] to run linters in the cluster. Modified a TypeScript file? "arc lint" will make sure your TypeScript pod is up-to-date and run the linter there, etc.
We're using custom tooling which is faster than https://github.com/GoogleContainerTools/skaffold, but it's the same approach.
Thinking about open sourcing it.
[1]: Phabricator's CLI client