diff --git a/src/repocat/cli/archive.py b/src/repocat/cli/archive.py
index 2018145..d3f726f 100644
--- a/src/repocat/cli/archive.py
+++ b/src/repocat/cli/archive.py
@@ -28,7 +28,7 @@ def archive_repo(source: Path, target_dir: Path, dry_run: bool) -> Path:
         return archive_path
 
     with open(archive_path, "wb") as f:
-        cctx = zstandard.ZstdCompressor(level=20)
+        cctx = zstandard.ZstdCompressor(level=20, threads=-1)
         with cctx.stream_writer(f) as compressor:
             with tarfile.open(fileobj=compressor, mode="w|") as tar:
                 tar.add(source, arcname=source.name)