pairup.nvim
A Neovim plugin for inline AI pair programming: writing a marker comment such as cc: with an instruction and saving the file has Claude edit that file directly in place, with a separate marker for Claude to ask a clarifying question before proceeding.
pairup.nvim works through plain comment markers rather than a separate chat panel or overlay system: a command marker tells Claude to execute the instruction and edit the file directly, removing the marker when done; a constitution marker does the same but also extracts the underlying rule into the project's CLAUDE.md so it applies to future work; and a plan marker asks for a plan instead of a direct edit, wrapping the proposed change in conflict markers for the user to accept or reject before anything changes. Claude answers back with its own question marker when a request needs clarification, and the user replies by adding a command line beneath it.
A separate feature runs a second, autonomous Claude instance in a sibling git worktree for parallel development: while the user works in the main repository, this peripheral Claude works independently on its own branch, receiving a diff and implementing changes automatically whenever the user updates a design or specification file, with its own status line indicator and independent commits.
It is written in Lua for Neovim and licensed under MIT; version 4 removed an earlier overlay, session and RPC system in favor of this simpler marker-based editing.