diff --git a/pkgs/misc/source-and-tags/default.nix b/pkgs/misc/source-and-tags/default.nix
index 88ed7a47725..eb243aa4f9b 100644
--- a/pkgs/misc/source-and-tags/default.nix
+++ b/pkgs/misc/source-and-tags/default.nix
@@ -12,13 +12,12 @@
   # tag command must create file named $TAG_FILE
   sourceWithTagsDerivation = {name, src, srcDir ? ".", tagSuffix ? "_tags", createTagFiles ? []} :
     stdenv.mkDerivation {
-    phases = "unpackPhase buildPhase";
     inherit src srcDir tagSuffix;
     name = "${name}-source-with-tags";
     nativeBuildInputs = [ unzip ];
     # using separate tag directory so that you don't have to glob that much files when starting your editor
     # is this a good choice?
-    buildPhase =
+    installPhase =
       let createTags = lib.concatStringsSep "\n"
           (map (a: ''
             TAG_FILE="$SRC_DEST/${a.name}$tagSuffix"