Knowing of a product works for end users or not needs proper usability testing. But sometimes you want to do a quick, minimal check what user's think about your product.
Over the holidays I rewrote a service I had a couple of years ago that let's you run System Usability Scale (SUS) surveys quickly (SUS is an established 10-item questionnaire that results in a indicator score that shows if your users are likely to consider your product usable).
It rus on Django / Caddy / PG. I am keeping it free to use for now with the hope that more people will use SUS surveys to improve their products.
Happy for any feedback while I am fixing the last issues.