This is a new, open-source project along the lines of Dragon, currently in an early design and prototyping stage. You can find a design document here, and a Slack channel here.
This repository currently contains hydra-scala and a hydra-haskell directory with language-specific builds, as well as a common directory with YAML-based sources.
You can compile code with sbt compile, run it with sbt run, and sbt console will start a Scala 3 REPL.
Compile the project (and eventually install the executable) with stack install. Enter the GHCi REPL with stack ghci.