Too bad: the developers of Iron Danger announced on Steam, that the work on the native versions for Linux and MacOS has been canceled:

hepphep 14. Okt. um 11:41 Uhr
Hi,

Some update on this. We have playable development version for both, but unfortunately we ran to tons of issues with different configurations. For example with OSX there was lots of variety with different EGPUs behaving differently. While working nicely with some and breaking up totally in unexpected situation with other. The amount of work to get things work nicely with all required combinations proved to be much more work than we expected leading into situation that cost to finish the porting to quality level that we want exceeded even the highest expectations on possible sales on those platforms. Therefore we unfortunately cannot keep on working on those versions anymore and have just accept the losses of work already done with them.

It's a shame, because we really wanted to finish those, but reality slapped our face hard with that one.