PuzzleScript was developed by me (with the assistance/feedback of many other people + tools), Stephen Lavelle (@increpare). Programming puzzle games isn't all that hard in the grand scheme of things, but the barrier to entry is way higher than it needs to be.
It's not a general purpose game making tool, it's not even a general purpose puzzle game making tool. Or even a avatar-based turn-based puzzle game making tool - games like DROD don't work, or games with very nuanced behaviours, like Puzzles proved impossible. But it is a tool, and I think it might prove handy/enabling for a number of people, if one is accepting of its limitations.
I've worked on a lot of puzzle games, and decided on a particular group of those that could be handily modelled with a scripting language. I've seen someone do a similar pattern-matching system before (I can't remember who, though), but it was a lot less flexible - the movement system in this engine is what gives it its real power.
Getting the engine out the door, so to speek, took several weeks of full-time, unreumerated work, and no doubt there's plenty more to come. I am not a wealthy man, I'm an impoverished, self-employed independent game developer whose involvement with such projects amounts to happy indiscretions. If you appreciate this piece of software, please consider chipping some money my way, okay? :)
I've you've made something cool with the engine, please let me know ( firstname.lastname@example.org or @increpare ) - I'd love to highlight (and maybe even host as examples) wonderful things that people've made with this.