Currently, the Keyman Developer IDE runs only on Windows and it would be an extensive effort to get it running on WINE or building cross-platform. However, the command line tools (downloadable from Download Keyman Developer 16.0 “kmcomp Compiler”) run fine in WINE. All of the source files for keyboard layouts (barring images) are UTF-8 text files so they can be edited with any editor. You may find it easiest to copy a keyboard out of the keyboards repository rather than starting from scratch.
We are starting a project to develop a cross-platform (and electron / web-based) version of Keyman Developer; we are seeking funding and/or partners to expedite development of this. If you have any ideas in this area, I’m all ears!
@CraigC as @Marc indicated you can use kmcomp with wine. On my Linux distribution I found I needed to create a 64-bit profile to use with wine. Creating a kmn file generating a kmx file is straightforward. The kps file and mobile layout files are doable but care is needed to assure that valid source files are generated. I have found on Linux that Visual Studio Code is a good choice for the editor.