This looks very cool. All other tiling window manager implementations I've seen for Windows fall short in some way, but this looks as close to something like sway or i3 as possible. Keeping the design simple by configuration through message passing is cool.

But the license is a dealbreaker for me. On one hand, I like that the license terms are short and easy to understand. In that regard, it blows other proprietary software out of the water. On the other hand, I know I'd be tempted to tinker with the internals at some point, and the license forbids me from doing that. Even if in practice the maintainer accepts illicit patches, I'd rather not spend my time contributing unpaid to something proprietary, so I'd rather use and contribute to some open source alternative.

But the real non-starter is that I only use Windows at work, and the license forbids me from using the software there in the first place.