diff --git a/nix/default.nix b/nix/default.nix
index 21244c3675..0f21e5ce56 100644
--- a/nix/default.nix
+++ b/nix/default.nix
@@ -9,18 +9,17 @@ let
   # The `common` repo provides code (mostly Nix) that is used in the
   # `infra`, `dfinity` and `sdk` repositories.
   #
-  # To conveniently test changes to a local `common` repo you point
-  # the `COMMON` environment variable to it. The path should be
-  # relative to the root of the `sdk` repo. For example:
+  # To conveniently test changes to a local `common` repo you set the `COMMON`
+  # environment variable to an absolute path of it. For example:
   #
-  #   COMMON="../common" nix-build -A rust-workspace
+  #   COMMON="$(realpath ../common)" nix-build -A rust-workspace
   commonSrc =
     let localCommonSrc = builtins.getEnv "COMMON"; in
     if localCommonSrc != ""
-    then ../. + "/${localCommonSrc}"
+    then localCommonSrc
     else builtins.fetchGit {
       url = "ssh://git@github.com/dfinity-lab/common";
-      rev = "9f7598dfe4a5d19985d6a61dfc1c0fe2b286ce91";
+      rev = "633ff01d07bac061001d5a2713363ef3de5df2df";
     };
 in import commonSrc {
   inherit system crossSystem config;