Whole lottie tools out there
From ugly-GPL-free to inspirational procedural animation, your alternatives to Adobe After Effects. — Lottie is an incredibly successful format for describing vector animation. Vector means shapes moving and changing, as opposed to a video-like animation where you have pixel-by-pixel changes every 1/24th second. Storing shapes and changes is dramatically more efficient in space. Update 2022–02–11 — see LottieLab new tool added at end.