[pm]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_expand/proc_macro/index.html
[pms]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_expand/proc_macro_server/index.html
-TODO: more here.
+TODO: more here. [#1160](https://github.com/rust-lang/rustc-dev-guide/issues/1160)
### Custom Derive
Custom derives are a special type of proc macro.
-TODO: more?
+TODO: more? [#1160](https://github.com/rust-lang/rustc-dev-guide/issues/1160)