diff --git a/.github/workflows/test-per-system.yml b/.github/workflows/test-per-system.yml
index e0c586e..f3550f9 100644
--- a/.github/workflows/test-per-system.yml
+++ b/.github/workflows/test-per-system.yml
@@ -18,7 +18,7 @@ on:
         type: string
 
 env:
-  nixpkgs_channel: nixpkgs=channel:nixos-25.11
+  nixpkgs_channel: nixpkgs=channel:nixos-25.05
 
 jobs:
   simple-build:
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 2cfadd9..e974b11 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -7,7 +7,7 @@ on:
   workflow_dispatch:
 
 env:
-  nixpkgs_channel: nixpkgs=channel:nixos-25.11
+  nixpkgs_channel: nixpkgs=channel:nixos-25.05
 
 jobs:
   test: