nvim-parinfer is a Neovim plugin that uses Chris Oakman's parinfer-lua to implement the parinfer algorithm. Parinfer automatically balances parentheses as you type when working in Lisp-family languages. Unlike parinfer-rust, it requires no external dependencies: simply install and go.
nvim-parinfer uses sane defaults that should "just work". You can see the
(small) list of configuration knobs in :help parinfer.
lua/parinfer.lua is licensed ISC by Chris Oakman.
Everything else is licensed GPLv3 or later by Gregory Anders.