First, let's **[download the latest tarball](https://gitlab.com/librewolf-community/browser/source/-/jobs/artifacts/main/raw/librewolf-95.0.2-4.source.tar.gz?job=build-job)**. This tarball is the latest produced by the [CI](https://gitlab.com/librewolf-community/browser/source/-/jobs).
This would create a _mozilla-unified_ folder in our 'build' folder, or basically anywhere that is your current working directory. It takes about an hour for me to complete, but it needs to be done only once. This step might fail and cause problems. Hack a bit, and if that fails you can ask on our [Gitter](https://gitter.im/librewolf-community/librewolf)/[Matrix](https://matrix.to/#/#librewolf:matrix.org) channels. There is no need to actually build _mozilla-unified_ (Mozilla Nightly) itself, nor is the folder needed to build LibreWolf. So you can remove it: `rm -rf mozilla-unfied` if you don't plan on using/exploring it.
Since Firefox 95.0, we need to install an additional library, the **'wasi sdk'**. This library sandboxes wasm libraries, which is what we want, but it's still experimental for us to include properly.
A few resources:
* mozilla.org: [WebAssembly and Back Again: Fine-Grained Sandboxing in Firefox 95](https://hacks.mozilla.org/2021/12/webassembly-and-back-again-fine-grained-sandboxing-in-firefox-95/).
* [Compiling C to WebAssembly using clang/LLVM and WASI](https://00f.net/2019/04/07/compiling-to-webassembly-with-llvm-and-clang/).
* [Firefox 95 on POWER](https://www.talospace.com/2021/12/firefox-95-on-power.html).
To setup the wasi sdk _headers_, you can use _librewolf-95.0.2/lw/setup-wasi-linux.sh_. Please note that this script is a bit experimental and not all kinks have been worked out, but it should work.
This might not be enough on all systems. Some systems have the wasi-libc library already installed, and some don't. It depends on the installed version of Clang/LLVM it seems, which should be v8 or above. On debian-based systems: `sudo apt install wasi-libc`, on Arch: `https://archlinux.org/packages/community/any/wasi-libc/` (`pacman -Syu wasi-libc`). Instructions for macos/windows and perhaps other Linux distro's will be added here soon.
Or, the other option is to not use these sandbox libraries: In this case we can't use our standard _mozconfig_ symlink from _mozconfig.new_ into _mozconfig.new.without-wasi_. In that case you have to type something along the lines of:
This source repo supports all that, because it uses these same things to produce the tarball. As far as I can tell, the mapping from Common to Source would be:
With this mapping, I hope that other builders that can't use our tarball (afterMozilla project, weird distro's), still use the same source/patches as the builders that do use it.
The file [assets/patches.txt](https://gitlab.com/librewolf-community/browser/source/-/blob/main/assets/patches.txt) defines what patches go in. These are not the only patches a builder will use, weird distro's etc, will use additional patches. those patches can live in the repo of that distro, or in a subfolder here. I hope this gives everybody the freedom to build anyway they please, like in Common, but with the added benefit that we produce a source tarball.
The repository has a short [example shell script](https://gitlab.com/librewolf-community/browser/source/-/blob/main/scripts/fetch-build.sh) on how to use the new-style tarball approach instead of the older patching-it-yourself approach.