The calculator app on this site looks modest — twelve digits, four operations, a keyboard listener. Building it gave me a nostalgia I didn’t quite expect.

Somewhere between schoolwork and work, math became something we perform on behalf of a spreadsheet. But pressing those buttons again — those reassuring new numbers appearing at every tap — took me straight back to the years of making arithmetic behave myself, for no reason beyond making it behave.

Maybe that’s the secret of the pleasant side projects: they smuggle the fun back in undetected, without any boring “you need to feel productive” paperwork attached.

So this is a small cheer for the number lovers. Open the calc, mash some keys, and remember that once upon a time math was an afternoon well wasted.