diff --git a/.tangled/workflows/publish.yml b/.tangled/workflows/publish.yml
index c162a5c..c1787a8 100644
--- a/.tangled/workflows/publish.yml
+++ b/.tangled/workflows/publish.yml
@@ -2,11 +2,16 @@ when:
   - event: [push, manual]
     branch: [main]
 
-engine: nixery
+engine: microvm
+image: nixos
+
+virtualisation:
+  docker: true
 
 dependencies:
   nixpkgs: [deno]
 
 steps:
-  - command: deno i
-  - command: deno task build
+  - command: |
+      set -euo pipefail
+      docker build -t "testing/otto" .