Recently there’s been some work going on Tree-sitter grammar for PureScript. It is now finished and a Neovim (and some other editors) integration is available.
Guides (really simple) on how to install it for different editors are available here. VS Code currently has no official support for Tree-sitter, but Microsoft are working on it.
Primarily, editors integration. A tree-sitter grammar is a CST parser, and as such offers editors fairly deep insight into the text they’re rendering, which in turn enables features like “smarter” and faster highlighting and code navigation.