treesitter gives us a uniform interface to parse and manipulate code, which is awe-inspiring work. I wish tree-sitter could have more contributors to the core library. It still has a lot of improvement space.

Say, like performance. tree-sitter's initial parsing speed can be easily beaten by a carefully hand-crafted parser. Tree-sitter, written in C, has a similar JavaScript parsing speed as Babel, a JS-based parser. See the benchmark https://dev.to/herrington_darkholme/benchmark-typescript-par...