Last year I bought a second computer for my music studio. I wanted to use the same set of 2 monitors and wired keyboard + trackpad on both machines.

I wrote simple scripts to switch my monitor inputs with keyboard shortcuts (even simpler with Lunar, amazing new Mac app — https://lunar.fyi), which saved me from having to press annoying input-source buttons.

But I couldn't for the life of me find a simple, suitable software controllable KVM switch. That still requires the hardware button to be controlled, so frustrating.

For full software no hardware kvm solution, there is Microsoft Garage Mouse Without Borders. Wish it was open source. Mostly useful for multi monitor setup where you don’t need to change sources just change keyboard and mouse. For soft switching source I use a script to send DDC commands to the monitor

Isn't that functionnaly the same as Synergy (which was opensource but isn't anymore), and it's opensource fork Barrier (https://github.com/debauchee/barrier) ?