docs: updated docs for cranelift and wasm-opt

docs/next/en-US/reference/compilation-times.md

@@ -6,4 +6,14 @@ The first step in addressing this is to figure out whether your app needs export
 
 The next step is pretty trivial: `rustup override set nightly`. This command will set the default toolchain in your project (you have to run that command in your proejct directory) to `nightly`, which tends to nearly cut compile times in half! In general, the nightly compiler will be much faster than the stable one, because it uses all sorts of unstable features that improve compilation times. If you want maximum assurances though, switch back to the stable compiler before running `perseus deploy` so your production app is secured against any nightly compiler bugs (which do happen) and you get the best of both worlds.
 
-From here, we get a little more radical.
+From here, we get a little more radical. There's something called [Cranelift](), a compiler backend that can be used [for Rust]() to speed up development compilation times. Of course, the sacrifice here is runtime speed, but as long as you build with the usual compiler for production, you again get the best of both worlds. To set this up, you'll need to download the latest version of [this project](https://github.com/bjorn3/rustc_codegen_cranelift) from [here](https://github.com/bjorn3/rustc_codegen_cranelift/actions?query=branch%3Amaster+event%3Apush+is%3Asuccess) (click on the most recent action run, and then download the appropriate artifact). Then, unzip that (twice, there's a nested zip folder) and you'll get a `build/` folder, which you can put anywhere on your system. Then, add the contents of that (which should contain `cargo-clif` and `rustc-clif`) to your system's `PATH` (tutorial [for Windows](https://stackoverflow.com/a/44272417), and [for Linux/MacOS](https://linuxize.com/post/how-to-add-directory-to-path-in-linux/)).
+
+With that done, any new shell (you may have to log out and back in again) will have `cargo-clif` supported as a command! You can verify this by confirming that `cargo-clif -h` results in a help page being printed. This binary acts as a drop-in replacement for `cargo`, using the Cranelift backend instead. Note that you should only ever use this for development, it's not suitable for production, where you should use the normal `cargo` instead.
+
+The easiest way to get Perseus to use this, instead of the usual `cargo`, is to set `PERSEUS_CARGO_PATH=cargo-clif` (you might do this for a single command, or you might add it to an initialization script to run on all `perseus` commands). With that done, you can run `perseus export -w`/`perseus serve -w`, and, after a while of waiting, you should find your app built! Note that this will take a while the first time because Cranelift has to rebuild everything built with the usual `cargo`.
+
+**Remember:** do NOT use `cargo-clif` in production!
+
+*Note:* currently, `PERSEUS_CARGO_PATH` does not take effect in Wasm builds, due to an upstream issue in `wasm-pack`. In future, this will be supported, and compile times should be able to be shortened even further!
+
+After applying all the optimizations herein, a testing benchmark of measuring the time taken to run `perseus build` with the bleeding-edge version of the CLI in development mode on the `basic` example, changing a hardcoded state property, went from taking 28 seconds with the stable compiler and no target directory separation to just 7 seconds, when Cranelift and nightly were used along with the target directory separation now inbuilt into Perseus. In other words, you can cut Perseus' compile times by 75%!

docs/next/en-US/reference/deploying.md

@@ -34,4 +34,11 @@ To make this work, you should also add the following to your `Cargo.toml` under
 wee_alloc = "0.4"
 ```
 
+Finally, for another small cut to bundle sizes, you can set `wasm-opt`, a tool that `wasm-pack` runs automatically (and the Perseus CLI runs `wasm-pack`) to optimize for size by adding the following to your `Cargo.toml`:
+
+```toml
+[package.metadata.wasm-pack.profile.release]
+wasm-opt = [ "-Oz" ]
+```
+
 You can find more information about optimizing Wasm bundle sizes [here](https://rustwasm.github.io/book/reference/code-size.html#optimizing-builds-for-code-size).