What a donation buys
Days. Deki is a C++ engine, a visual editor and twenty-six packages, written by one person around a full-time job. The parts that make it good to use need a whole clear day rather than an hour of enthusiasm: documentation, bringing up a new board, cutting a release, the unglamorous polish.
Then hardware. Every device the engine supports is a device that was bought, wired up and left on a desk. The next one on the list starts as an order.
You will see where it went
This turns into things you can check: a release with a date on it, a board that works, a page of documentation that was not there last month. The blog says what shipped and Discord is where it happens in the open, so you can watch your money land.
Free for everyone
Nothing is gated and nothing is going to be. The same engine, the same editor, the same packages, whether you give or not. That is the thing worth paying for: you are not buying a better copy for yourself, you are keeping the good one free for everybody who picks it up.
If you want something specific built for you, that is a different conversation and a completely normal one. Start it on Discord or by email.