Curious to hear about positive experiences using APIs and libraries and what made the experience positive. Easy to use? Good documentation? Minimal code?
I'll start - While it's not perfect, I have really enjoyed using Qt for creating desktop applications. The API documentation itself is pretty good - although I'd say the official examples could be more accessible. Overall, it provides a relatively easy way to make cross-platform desktop apps (and more, although that's not where my experience is) without compromising on performance.