message: explaining that  and  must be cached alongside binaries installed with
diff: @@ -58,8 +58,12 @@ However, caching the entire directory is often inefficient as it will contain do
  If we depend on a crate such as `serde 1.0.92` and cache the entire `$CARGO_HOME` we would actually cache the sources twice, the `serde-1.0.92.crate` inside `registry/cache` and the extracted `.rs` files of serde inside `registry/src`.
  That can unnecessarily slow down the build as downloading, extracting, recompressing and reuploading the cache to the CI servers can take some time.
  -It should be sufficient to only cache the following directories across builds:
  +If you wish to cache binaries installed with [`cargo install`], you need to cache the `bin/` folder and the `.crates.toml` and `.crates2.json` files.
  +It should be sufficient to cache the following files and directories across builds:
  +
  +* `.crates.toml`
  +* `.crates2.json`
  * `bin/`
  * `registry/index/`
  * `registry/cache/`
  