diff --git a/pkgs/build-support/upstream-updater/update-walker.sh b/pkgs/build-support/upstream-updater/update-walker.sh
index 78c61dd2b82a..8d7a6b219f16 100755
--- a/pkgs/build-support/upstream-updater/update-walker.sh
+++ b/pkgs/build-support/upstream-updater/update-walker.sh
@@ -82,20 +82,26 @@ version () {
 }
 
 ensure_version () {
+  echo "Ensuring version. CURRENT_VERSION: $CURRENT_VERSION" >&2
   [ -z "$CURRENT_VERSION" ] && version '.*-([0-9.]+)[-._].*' '\1'
 }
 
 ensure_target () {
+  echo "Ensuring target. CURRENT_TARGET: $CURRENT_TARGET" >&2
   [ -z "$CURRENT_TARGET" ] && target default.nix
 }
 
 ensure_name () {
+  echo "Ensuring name. CURRENT_NAME: $CURRENT_NAME" >&2
   [ -z "$CURRENT_NAME" ] && name "$(basename "$CONFIG_DIR")"
   echo "Resulting name: $CURRENT_NAME"
 }
 
 ensure_choice () {
-  [ -n "NEED_TO_CHOOSE_URL" ] && {
+  echo "Ensuring that choice is made." >&2
+  echo "NEED_TO_CHOOSE_URL: [$NEED_TO_CHOOSE_URL]." >&2
+  echo "CURRENT_URL: $CURRENT_URL" >&2
+  [ -n "$NEED_TO_CHOOSE_URL" ] && {
     version_link '[.]tar[.]([^./])+$'
     unset NEED_TO_CHOOSE_URL
   }
@@ -106,12 +112,19 @@ ensure_choice () {
   }
 }
 
+ensure_hash () {
+  echo "Ensuring hash. CURRENT_HASH: $CURRENT_HASH" >&2
+  [ -z "$CURRENT_HASH" ] && hash
+}
+
 hash () {
   CURRENT_HASH="$(nix-prefetch-url "$CURRENT_URL")"
+  echo "CURRENT_HASH: $CURRENT_HASH" >&2
 }
 
 name () {
   CURRENT_NAME="$1"
+  echo "CURRENT_NAME: $CURRENT_NAME" >&2
 }
 
 retrieve_version () {
@@ -196,7 +209,7 @@ do_regenerate () {
 }
 
 do_overwrite () {
-  hash
+  ensure_hash
   do_regenerate "$1" > "$1.new.tmp"
   mv "$1.new.tmp" "$1"
 }