What playing it taught me
I built Haystack to test a talk I love, Jan Willem Nijman's "The Art of Screenshake". Every juice trick from it sits on its own number key. Then I played it, and nearly every bug I found was one of his lessons arriving in person.
Lower the enemy HP. His first trick. At 1,600 straws and fifteen per throw, the game was a chore. Six hundred and fifty straws and a bigger hand fixed it in one line.
Permanence. Straws that reached the cart used to vanish. Now they pile up in a gold mound, and the ones that miss stay on the grass. You can see your work.
Give a reason not to press. Greedy handfuls now spill on the way, so grabbing less is a real choice.
The world has walls. One strong throw sent the needle to x = 8,628, far off the edge of the world, and the round could never end. No amount of screenshake forgives a soft-lock.
Gravity, but only where you dug. Dig out the bottom and the top used to hang in the air. My first fix collapsed the whole pile at once, because a random pile has gaps everywhere. The second only checks where you just dug, and a sliding straw stops on the first hay it touches. Sand behaves like that.
Do what the words promise. The hint said to drag hay into the cart, but letting go over the cart flung it off the top of the screen. Now letting go over the cart drops it in. That was the biggest improvement of the night, and it wasn't juice at all. It was keeping a promise.
Near the end of the talk he says you're the worst playtester of your own game, because you steer around your own bugs without noticing. I wrote this one, so I knew where every straw was. Every bug I found still came from a moment I lost control: the window resizing under me, a throw that went somewhere I didn't aim. The mess is the test.