diff --git a/.envrc b/.envrc
index aa69d57..17cddaa 100644
--- a/.envrc
+++ b/.envrc
@@ -4,8 +4,14 @@ git config --local core.hooksPath "$PWD"/.githooks
 test -d .direnv || mkdir -p .direnv
 now="$(date +%Y-%m-%d)"
 if ! test -s .direnv/pull-date || test "$now" != "$(cat .direnv/pull-date)"; then
+  git checkout -- flake.lock
   git pull --rebase --autostash
-  nix flake update
+  nix flake lock \
+    --update-input nixpkgs \
+    --update-input unstable \
+    --update-input home-manager \
+    --update-input nixos-hardware \
+    --update-input pbsds-papers
   echo "$now" > .direnv/pull-date
 fi