diff --git a/decision-task/run.py b/decision-task/run.py
index 2660ff51196..9c623dafe82 100644
--- a/decision-task/run.py
+++ b/decision-task/run.py
@@ -77,7 +77,7 @@ image_build_task = create_task(
         "dind": True,  # docker-in-docker
     },
     artifacts=[
-        ("image.tar.gz", "/image.tar.gz"),
+        ("image.tar.lz4", "/image.tar.lz4"),
     ],
 )
 
@@ -88,7 +88,7 @@ build_task = create_task(
     image={
         "type": "task-image",
         "taskId": image_build_task,
-        "path": "public/image.tar.gz",
+        "path": "public/image.tar.lz4",
     },
 
     artifacts=[
diff --git a/docker-image-build-task.sh b/docker-image-build-task.sh
index 33178293bb7..54649313efd 100755
--- a/docker-image-build-task.sh
+++ b/docker-image-build-task.sh
@@ -9,4 +9,4 @@ apt-get update -q
 apt-get install -qy --no-install-recommends docker.io
 docker version
 ./docker/build.sh "$image"
-docker save "$image" | gzip > /image.tar.gz
+docker save "$image" | lz4 > /image.tar.lz4