diff --git a/ci-tools/update-nixpkgs b/ci-tools/update-nixpkgs
index 1d673abe80e8f8dc69a1025e6e653a9daf140c7b..4e573981a4cb0220a94c00a3ea1021958e48e024 100755
--- a/ci-tools/update-nixpkgs
+++ b/ci-tools/update-nixpkgs
@@ -12,6 +12,8 @@ set -eux -o pipefail
 HOST="whetstone.private.storage"
 
 setup_ssh() {
+    export HOME="${PWD}"
+
     # -s makes the output sh compatible, in case it can't detect this for
     # itself.
     eval $(ssh-agent -s)