Rough.js is a light weight (~8k), Canvas based library that lets you draw in a sketchy, hand-drawn-like, style. The library defines primitives to draw lines, curves, arcs, polygons, circles, and ellipses. It also supports drawing SVG paths.
If you have Workly imported on your web page (~1k only), RoughJS will automatically offload all processing to a web worker – freeing up your main UI thread. This is great when creating complex drawings using RoughJs like maps.