If you don't ship an API, your customers will build one

If your software has a web interface but no API, your customers will automate the web interface. I know, because I’ve done it. First for Sportlink, the member administration system Dutch football clubs have to use. And today, again, for another system our club runs on. Neither vendor offers an API for the data we need. Both now have a headless browser logging in to their app several times a day, clicking through screens and pulling data out. That’s not a complaint about my code. It’s a question for the vendors: why make your customers do this? A volunteer with an afternoon I build Rondo, the club management app my football club uses. It needs member data: names, teams, parents, committees, photos. All of that lives in Sportlink Club, which the KNVB mandates. Sportlink has no way to get that data out programmatically. So Rondo Sync uses Playwright to launch a headless Chrome, log in, generate the two-factor code, and walk through Sportlink’s screens. It runs four times a day. It has a…