diff --git a/roles/nix-mio-ops.nix b/roles/nix-mio-ops.nix
new file mode 100644
index 0000000..81cfafa
--- /dev/null
+++ b/roles/nix-mio-ops.nix
@@ -0,0 +1,17 @@
+# Use the mio-ops build servers
+
+{
+  nix = {
+    distributedBuilds = true;
+    buildMachines = [
+      {
+        hostName = "cuallaidh.mcwhirter.io";
+        maxJobs = 64;
+        sshKey = "/root/.ssh/id_nixops_ed25519";
+        sshUser = "craige";
+        system = "x86-64";
+        supportedFeatures = [ "big-parallel" ];
+      }
+    ];
+  };
+}