Simplest I can think of: $ echo 'cat > "$@"' >editor $ chmod +x editor $ GIT_EDITOR=./editor git commit -a stuff [master b2d3915] stuff

Simplest I can think of: $ echo 'cat > "$@"' >editor $ chmod +x editor $ GIT_EDITOR=./editor git commit -a stuff [master b2d3915] stuff 1 file changed, 1 insertion(+) You'll need to hit enter before ^D. You can add simple Emacs-like keybindings by changing that into $ echo 'rlwrap cat > "$@"' >editor Or just learn ed: $ GIT_EDITOR=ed git commit --amend -a 256 1c stuff and more stuff . w 271 [master c5092a6] stuff and more stuff Date: Thu Apr 6 12:58:18 2017 +0200 1 file changed, 1 insertion(+) (the numbers are ed telling me how much was read and written; `1c` means change the first line; `.` means I'm done inserting (go back to command mode) and `w` means write/save; exit with ^D)