With emacs I can nix-repl> :u inputs.emacs-overlay.packages.x86_64-linux.emacsUnstable-nox and then emacs.
I would love to do the same with neovim to debug my config a bit.
nix-repl> :u inputs.neovim-nightly-overlay.packages.x86_64-linux.default and then running nvim just times out though.
Does anyone if that should work already ?