diff --git a/pkgs/top-level/go-packages.nix b/pkgs/top-level/go-packages.nix
index 567259dfebef..17cc343b656a 100644
--- a/pkgs/top-level/go-packages.nix
+++ b/pkgs/top-level/go-packages.nix
@@ -8,7 +8,7 @@ let
 
   buildFromGitHub = { rev, date ? null, owner, repo, sha256, name ? repo, goPackagePath ? "github.com/${owner}/${repo}", ... }@args: buildGoPackage (args // {
     inherit rev goPackagePath;
-    name = "${name}-${if date != null then date else stdenv.lib.strings.substring 0 7 rev}";
+    name = "${name}-${if date != null then date else if builtins.stringLength rev != 40 then rev else stdenv.lib.strings.substring 0 7 rev}";
     src  = fetchFromGitHub { inherit rev owner repo sha256; };
   });