@tomaka17 If you need to change it backwards compatibily, then Cargo's patch can help. Overall though I think that's a good reason to long-term move public API crates into std or some "official" project (with equivalent bus factor to Rust itself, at least theoretically).
@ArvidGerstmann@rustlang You may be interested in https://t.co/BbNX0DBOTo which tries to optimize for size over performance but provides similar usability advantages to serde. It's less production-ready, though.