No idea if anyone here is interested in this, or whether this is even the right place to post, but I had some fun last weekend 
I recently discovered Beyond All Reason, a modern RTS game build on the popular open-source Spring game engine.
They do offer Linux versions of the launcher in form of AppImage and Flatpak, which would probably have worked. (I did not try)
But I wanted to know if I could write a nix derivation myself. So i did.
This is just the launcher, not the engine. (Although, Spring is already in nixpkgs, so that might not be much harder.)
All necessary resources are on GitHub under the beyond-all-reason organization.
Ingame lobby: GitHub - beyond-all-reason/BYAR-Chobby
Launcher: GitHub - beyond-all-reason/spring-launcher: Launcher for SpringRTS games
Downloader: GitHub - beyond-all-reason/pr-downloader: console downloader for spring maps/games written in c++
The launcher will download the engine and the game to ~/Beyond All Reason/.
I wrapped the result in steam-run, so that the game starts without further patching. The launcher itself is just an Electron app and does not require it.
{ lib
, stdenv
, fetchFromGitHub
, buildNpmPackage
, runCommand
, nodejs
, electron
, butler
, steam-run
, jq
, xorg
, libcxx
# dependencies for pr-downloader
, gcc
, cmake
, curl
, pkg-config
, jsoncpp
, boost
, minizip
}:
# This builds the launcher for Beyond All Reason.
# Which can then download the engine, the lobby, and the game.
# Starts the launcher with steam-run, so that the game starts without further
# patching.
let
version = "1.1861.0";
srcs = {
# Contains the configuration for the launcher.
byar-chobby = fetchFromGitHub {
owner = "beyond-all-reason";
repo = "BYAR-Chobby";
rev = "v${version}";
sha256 = "sha256-YnOW63Z8A/W89TeeMDJcVKjA1ErATvPHzm26wQdWH2I=";
};
spring-launcher = fetchFromGitHub {
owner = "beyond-all-reason";
repo = "spring-launcher";
rev = "439a9b7b7d835691267ad13586d0efc763d39b60";
sha256 = "sha256-26bDjlbh2lppMC6+6pyqdaSNbVrwKPj4ckMK0LZleQY=";
};
};
# From: https://github.com/beyond-all-reason/BYAR-Chobby/blob/1ee341043b6bb1f488ed5aab5d02c85018c572ed/.github/workflows/launcher.yml
src = runCommand "byar-launcher-src-${version}"
{
buildInputs = [ nodejs jq ];
} ''
cp -r ${srcs.byar-chobby} BYAR-Chobby
cp -r ${srcs.spring-launcher} launcher
chmod -R +w *
echo --- Patch launcher with dist_cfg
cp -r BYAR-Chobby/dist_cfg/* launcher/src/
for dir in bin files build; do
mkdir -p launcher/$dir
if [ -d launcher/src/$dir/ ]; then
mv launcher/src/$dir/* launcher/$dir/
rm -rf launcher/src/$dir
fi
done
echo --- Make package.json
GITHUB_REPOSITORY=beyond-all-reason/BYAR-Chobby
cd BYAR-Chobby
export PACKAGE_VERSION=${version}
echo "Making build for version: $PACKAGE_VERSION"
node build/make_package_json.js ../launcher/package.json dist_cfg/config.json $GITHUB_REPOSITORY $PACKAGE_VERSION
cd ..
echo --- Patching package.json
# Rebuilding electron would fail: It tries to access github.com.
# And we do not need it anyway.
jq 'del(.devDependencies.electron)' launcher/package.json > temp
mv temp launcher/package.json
jq 'del(.packages."".devDependencies.electron)' launcher/package-lock.json \
| jq 'del(.packages."node_modules/electron")' > temp
mv temp launcher/package-lock.json
echo --- Force dev mode to prevent launcher-update
sed -i 's/const isDev = .*\;/const isDev = true\;/' launcher/src/launcher_wizard.js
mv launcher $out
'';
nodeModules = buildNpmPackage {
inherit src version;
pname = "byar-launcher-package";
npmDepsHash = "sha256-cCUtkycZ0bpLwcCfBjf+rTeoMHN7jIxcYCtyrB4rC8A=";
npmFlags = [ "--legacy-peer-deps" ];
dontNpmBuild = true;
passthru = {
buildInputs = [
nodejs
libcxx
xorg.libX11
];
};
installPhase = ''
mv node_modules $out
'';
};
pr-downloader = stdenv.mkDerivation rec {
pname = "pr-downloader";
version = "master";
src = fetchFromGitHub {
owner = "beyond-all-reason";
repo = "pr-downloader";
rev = "79b605d013a0c5a92090b3892e8e0c0aeccac2a8";
sha256 = "sha256-noroFiv2wAUCgI1ne2sP0PVBxIf20D+m5oa5+pk2OXQ=";
fetchSubmodules = true;
};
buildInputs = [
gcc
cmake
curl
pkg-config
jsoncpp
boost
minizip
];
postInstall = ''
mkdir $out/bin
mv $out/pr-downloader $out/bin
'';
};
in
stdenv.mkDerivation {
inherit src version;
pname = "byar-launcher";
phases = [ "buildPhase" ];
buildPhase = ''
mkdir -p $out/lib/dist
cp -r $src/* $out/lib/dist
chmod -R +w $out/lib/dist
cp -r ${nodeModules} $out/lib/dist/node_modules
rm $out/lib/dist/bin/butler/linux/butler
ln -s ${butler}/bin/butler $out/lib/dist/bin/butler/linux/butler
rm $out/lib/dist/bin/pr-downloader
ln -s ${pr-downloader}/bin/pr-downloader $out/lib/dist/bin/pr-downloader
mkdir -p $out/bin
echo '#!/bin/sh' > $out/bin/byar-launcher
echo "${steam-run}/bin/steam-run ${electron}/bin/electron $out/lib/dist" >> $out/bin/byar-launcher
chmod +x $out/bin/byar-launcher
'';
}
At some point in the future it could be nice to have the launcher as part of nixpkgs, but currently there is still a lot of development (and most importantly renaming) happening, so that would probably be wasted effort.
Anyway, a Steam release is planned …
(I did not test multiplayer, but I see no reason why it would not work.)