Create nix-modpack

packages/mkClient.nix

@@ -0,0 +1,66 @@
+{
+  pkgs,
+  bootstrap,
+  ...
+}:
+
+{
+  packUrl,
+  gameVersion,
+  loaderUid,
+  loaderVersion,
+}:
+
+pkgs.stdenvNoCC.mkDerivation {
+  name = "minecraft-client";
+
+  dontUnpack = true;
+
+  mmcpack = ''
+    {
+      "components": [
+        {
+          "important": true,
+          "uid": "net.minecraft",
+          "version": "${gameVersion}"
+        },
+        {
+          "uid": "${loaderUid}",
+          "version": "${loaderVersion}"
+        }
+      ],
+      "formatVersion": 1
+    }
+  '';
+
+  instancecfg = pkgs.writeText "instance.cfg" ''
+    [General]
+    ConfigVersion=1.2
+    InstanceType=OneSix
+    OverrideCommands=true
+    PreLaunchCommand=\"$INST_JAVA\" -jar packwiz-installer-bootstrap.jar ${packUrl}
+  '';
+
+  buildPhase = ''
+    # Remove env-vars
+    rm env-vars
+
+    # Add the mmc-pack
+    echo  $mmcpack > ./mmc-pack.json
+
+    # Add the instance-cfg
+    cp $instancecfg ./instance.cfg
+
+    # Add the bootstrap jar
+    mkdir ./minecraft
+    cp ${bootstrap} ./minecraft/packwiz-installer-bootstrap.jar
+
+    # Zip everything together
+    ${pkgs.zip}/bin/zip -r modpack.zip ./*
+  '';
+
+  installPhase = ''
+    mkdir $out
+    mv modpack.zip $out/
+  '';
+}

packages/mkServer.nix

@@ -0,0 +1,17 @@
+{
+  lib,
+  pkgs,
+  bootstrap,
+  ...
+}:
+
+{
+  packUrl,
+  server,
+  jre ? pkgs.jre,
+}:
+
+pkgs.writeShellScriptBin "minecraft-server" ''
+  ${lib.getExe jre} -jar ${bootstrap} -g -s server ${packUrl}
+  ${server}/bin/${server.name}
+''