The current target is Kepler, but when not using the Xtext support, it is possible to run at least on Juno, but even on Indigo (tested, but not extensively). The dependencies for o.e.handly and o.e.handly.ui should be relaxed to permit that.
The problem is that the Xtext support probably won't work for those baselines (even if it compiles, there might be hidden issues) and it's probably not worth it to try to test and support all older versions. This means that it's not posible to build the basic handly plugins and the Xtext support against the same targets, making the build process a bit tricky...
I think that so far I am the only user that requires pre-kepler support and I can handle it by including the handly code in my repo and keeping it updated until I can use the published binaries. But I think that the issue should be noted.
Should I create a bugzilla for this?