tig is an ncurses front end to git: walk the log with the arrow keys and the diff of whatever line you are on is one keystroke away. It reads a repository the way you would read a book — and it stages files too.
The demo opens tig's own repository, 400 commits deep. Move with j and
k, press Enter to open the commit under the cursor, t to see the tree
as it was at that commit, and s for the status view with three pending
changes in it. h lists every key. The VM is private to your browser tab;
nothing you type leaves it.