diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a7e7868..dc6a07a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -222,10 +222,10 @@ jobs:
           - key: url
             value: https://github.com/DeterminateSystems/nix-installer/releases/download/v0.18.0/nix-installer-x86_64-linux
             nix-version: "2.21.2"
-          # https://github.com/DeterminateSystems/nix-installer/pull/665
+          # https://github.com/DeterminateSystems/nix-installer/pull/738
           - key: pr
-            value: "665"
-            nix-version: "2.17.0"
+            value: "738"
+            nix-version: "2.18.1"
           # https://github.com/DeterminateSystems/nix-installer/tree/7011c077ec491da410fbc39f68676b0908b9ce7e
           - key: revision
             value: 7011c077ec491da410fbc39f68676b0908b9ce7e