diff --git a/pkgs/build-support/fetchgit/nix-prefetch-git b/pkgs/build-support/fetchgit/nix-prefetch-git
index 3cb115c5e6e6..a2dad2f698c3 100755
--- a/pkgs/build-support/fetchgit/nix-prefetch-git
+++ b/pkgs/build-support/fetchgit/nix-prefetch-git
@@ -105,7 +105,7 @@ fi
 
 init_remote(){
     local url=$1
-    clean_git init
+    clean_git init --initial-branch=master
     clean_git remote add origin "$url"
     ( [ -n "$http_proxy" ] && clean_git config http.proxy "$http_proxy" ) || true
 }