message: guix: Fallback to local build for substitute-enabled Guix users
diff: @@ -195,6 +195,7 @@ time-machine() {
  --commit=490e39ff303f4f6873a04bfb8253755bdae1b29c \
  --cores="$JOBS" \
  --keep-failed \
  + --fallback \
  ${SUBSTITUTE_URLS:+--substitute-urls="$SUBSTITUTE_URLS"} \
  ${ADDITIONAL_GUIX_COMMON_FLAGS} ${ADDITIONAL_GUIX_TIMEMACHINE_FLAGS} \
  -- "$@"
  @@ -344,6 +345,7 @@ EOF
  ${SDK_PATH:+--share="$SDK_PATH"} \
  --cores="$JOBS" \
  --keep-failed \
  + --fallback \
  --link-profile \
  ${SUBSTITUTE_URLS:+--substitute-urls="$SUBSTITUTE_URLS"} \
  ${ADDITIONAL_GUIX_COMMON_FLAGS} ${ADDITIONAL_GUIX_ENVIRONMENT_FLAGS} \
  