diff --git a/backup.nix b/backup.nix
index 181a1a2..17788a7 100644
--- a/backup.nix
+++ b/backup.nix
@@ -52,7 +52,7 @@ in {
       function upload () {
         name="$1"
 
-        age -r "$ageRecipient" | s3cmd put --config "${s3Cfg}" - "$s3Dir/$name.age"
+        age -r "$ageRecipient" | s3cmd put --config "${s3Cfg}" - "$s3Dir/$name.age" --multipart-chunk-size-mb=100
       }
 
       echo "Uploading config"