There's no money in it, is why. But it can be done to an extent. Grab a cheap external BT keyboard, a folding monitor stand, and Termux or a Scheme interpreter

There's no money in it, is why. But it can be done to an extent. Grab a cheap external BT keyboard, a folding monitor stand, and Termux or a Scheme interpreter, or a BASIC interpreter (I haven't looked, but I assume they exist), and you're there. I've done a lot of programming and writing on the phone that way.