This project has been abandoned. We don’t see any reason to write another issue management system, as there are plenty of good options already.
sachverhalt-cli is a command-line interface to sachverhalt written, extended
and configured in haskell.
You can find the specification for sachverhalt here. In essence, it is
a simple, extendable, JSON-based protocol for managing issues.
You can have a look at some examples and the server-side reference implementation.