Scrolling! If you move the cursor all the way to the bottom of the screen, it’ll shift the viewport down. And the opposite if you move the cursor to the top.

This took forever to get right. I kept breaking other things because I had juggle three different “perspectives”: the grid of characters output to the screen, the slice of the grid that’s the viewport, and the actual lines of the file. But it all works now.

I think next I might work on getting a demo set up. Most of the CLI binaries that I’ve downloaded before have used GitHub Releases, so I guess I should figure out how to make those work.