feat: add collecting nix derivation from source

collect-sources.nix

@@ -0,0 +1,62 @@
+{ rootDerivation
+, derivationName
+, stdenv
+, ... # added for future backwards compatibility
+}:
+let
+	config = builtins.fromJSON (builtins.readFile "${rootDerivation}/.git-third-party/config.json");
+	allRepoNames = builtins.attrNames config.repos;
+	makeDependentDerivation =
+		name:
+			let
+				cleanName = builtins.head (builtins.tail (builtins.match "^(.*/|)([^/]+)$" name));
+				myConfig = config.repos."${name}";
+				shouldFetchModules = !(builtins.hasAttr "submodules" myConfig) || myConfig.submodules != [];
+				base-src = builtins.fetchGit {
+					url = myConfig.url;
+					rev = myConfig.commit;
+					submodules = shouldFetchModules;
+					#fetchSubmodules = shouldFetchModules;
+					# fetchLFS = true;
+					shallow = true;
+				};
+		in stdenv.mkDerivation {
+			name = "git3party_${derivationName}_${cleanName}";
+			src = base-src;
+			patches =
+				builtins.map
+					(num: "${rootDerivation}/.git-third-party/patches/${name}/${toString num}")
+					(builtins.genList (x: x + 1) myConfig.patches);
+			phases = [ "unpackPhase" "patchPhase" "installPhase" ];
+
+			#outputHashMode = "recursive";
+
+			installPhase = ''
+				cp -r . "$out"
+			'';
+		};
+	dependentDerivations = builtins.map (name: { name = name; der = makeDependentDerivation name; }) allRepoNames;
+
+	cpFlags = "--no-preserve=ownership,mode --preserve=xattr";
+
+	copyLines = builtins.concatStringsSep "\n" ([
+		"cp ${cpFlags} -r '${rootDerivation}/.' ."
+	] ++ builtins.map (nameDer: "mkdir -p '${nameDer.name}'\ncp ${cpFlags} -r '${nameDer.der}'/. '${nameDer.name}'") dependentDerivations);
+in
+	stdenv.mkDerivation {
+		name = derivationName;
+
+		srcs = [
+			rootDerivation
+		] ++ (builtins.map (x: x.name) dependentDerivations);
+
+		phases = [ "unpackPhase" "installPhase" ];
+
+		#outputHashMode = "recursive";
+
+		unpackPhase = copyLines;
+
+		installPhase = ''
+			cp -r . "$out"
+		'';
+	}