Now that Serde’s code generation is stable and we no longer depend on Syntex, it no longer makes sense for our team to continue owning the Syntex stack.
The Syntex release process is outlined in this document. The gist of it is that the compiler’s libsyntax uses unstable features so you are responsible for backporting new functionality to work on old compilers - traditionally the stable compiler plus another two versions back.
If you think you may be interested, please let us know in serde-rs/syntex#114. Thanks!
If nobody needs Syntex updates so much that they would be willing to run the stack, we will be abandoning Syntex and Aster and Quasi.