diff --git a/binaries/system/readme.txt b/binaries/system/readme.txt
index e49744327e..b971defd84 100644
--- a/binaries/system/readme.txt
+++ b/binaries/system/readme.txt
@@ -61,5 +61,7 @@ Windows-specific:
 Archive builder:
 -archivebuild=PATH				system PATH of the base directory containing mod data to be archived/precached
 -archivebuild-output=PATH		system PATH to output of the resulting .zip archive (use with archivebuild)
+-archivebuild-compress			enable deflate compression in the .zip
+								(no zip compression by default since it hurts compression of release packages)
 -buildarchive					(disabled)
 
diff --git a/source/main.cpp b/source/main.cpp
index c2587129c2..5421d5c719 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -509,7 +509,7 @@ static void RunGameOrAtlas(int argc, const char* argv[])
 			zip = mod.Filename().ChangeExtension(L".zip");
 
 		CArchiveBuilder builder(mod, paths.Cache());
-		builder.Build(zip);
+		builder.Build(zip, args.Has("archivebuild-compress"));
 
 		CXeromyces::Terminate();
 		return;
diff --git a/source/ps/ArchiveBuilder.cpp b/source/ps/ArchiveBuilder.cpp
index 1d6b439f3f..3315075039 100644
--- a/source/ps/ArchiveBuilder.cpp
+++ b/source/ps/ArchiveBuilder.cpp
@@ -64,14 +64,14 @@ void CArchiveBuilder::AddBaseMod(const OsPath& mod)
 	m_VFS->Mount(L"", mod/"", VFS_MOUNT_MUST_EXIST);
 }
 
-void CArchiveBuilder::Build(const OsPath& archive)
+void CArchiveBuilder::Build(const OsPath& archive, bool compress)
 {
-	// Disable zip compression because it significantly hurts download size
-	// for releases (which re-compress all files with better compression
+	// By default we disable zip compression because it significantly hurts download
+	// size for releases (which re-compress all files with better compression
 	// algorithms) - it's probably most important currently to optimise for
 	// download size rather than install size or startup performance.
 	// (See http://trac.wildfiregames.com/ticket/671)
-	const bool noDeflate = true;
+	const bool noDeflate = !compress;
 
 	PIArchiveWriter writer = CreateArchiveWriter_Zip(archive, noDeflate);
 
diff --git a/source/ps/ArchiveBuilder.h b/source/ps/ArchiveBuilder.h
index 81dc405987..ad1ba4ad79 100644
--- a/source/ps/ArchiveBuilder.h
+++ b/source/ps/ArchiveBuilder.h
@@ -52,8 +52,9 @@ public:
 	/**
 	 * Do all the processing and packing of files into the archive.
 	 * @param archive path of .zip file to generate (will be overwritten if it exists)
+	 * @param compress whether to compress the contents of the .zip file
 	 */
-	void Build(const OsPath& archive);
+	void Build(const OsPath& archive, bool compress);
 
 private:
 	static Status CollectFileCB(const VfsPath& pathname, const FileInfo& fileInfo, const uintptr_t cbData);