diff --git a/TODO.md b/TODO.md
index 6c51f7c7..d7c217d4 100644
--- a/TODO.md
+++ b/TODO.md
@@ -149,6 +149,9 @@
 
 ### perf
 - debug nixos-rebuild times
+  - use `systemctl list-jobs` to show what's being waited on
+  - i think it's `systemd-networkd-wait-online.service` that's blocking this?
+    - i wonder what interface it's waiting for. i should use `--ignore=...` to ignore interfaces i don't care about.
 - add `pkgs.impure-cached.<foo>` package set to build things with ccache enabled
   - every package here can be auto-generated, and marked with some env var so that it doesn't pollute the pure package set
   - would be super handy for package prototyping!
diff --git a/hosts/common/polyunfill.nix b/hosts/common/polyunfill.nix
index 6d35630a..c3937185 100644
--- a/hosts/common/polyunfill.nix
+++ b/hosts/common/polyunfill.nix
@@ -20,6 +20,8 @@ in
       # from <repo:nixos/nixpkgs:nixos/modules/security/wrappers/default.nix>
       "fusermount"  #< only needed if you want to mount entries declared in /etc/fstab or mtab as unprivileged user
       "fusermount3"
+      "mount"  #< only needed if you want to mount entries declared in /etc/fstab or mtab as unprivileged user
+      "umount"
       # from <repo:nixos/nixpkgs:nixos/modules/programs/shadow.nix>
       "newgidmap"
       "newgrp"