diff --git a/.github/workflows/rig-3d.yml b/.github/workflows/rig-3d.yml
index 7889002..b1f1904 100644
--- a/.github/workflows/rig-3d.yml
+++ b/.github/workflows/rig-3d.yml
@@ -123,7 +123,8 @@ jobs:
           path: /tmp/rig-blender-gate/**/validation/*.json
   browser:
     name: Three.js browser playback and vertex comparison
-    runs-on: ubuntu-latest
+    # Playwright 1.55.0 supports Ubuntu 24.04; ubuntu-latest now selects 26.04.
+    runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
diff --git a/.gitignore b/.gitignore
index 74a44a3..d7cfd72 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,7 @@
 __pycache__/
 *.py[cod]
+/.venv/
+/.venv-rig/
 /output/
 
 # Reconstruct these exact production assets from the tracked source transports.
diff --git a/paseo.json b/paseo.json
new file mode 100644
index 0000000..7a301ef
--- /dev/null
+++ b/paseo.json
@@ -0,0 +1,14 @@
+{
+  "worktree": {
+    "setup": [
+      "node -e \"const{spawnSync}=require('node:child_process');const{join}=require('node:path');const py=process.platform==='win32'?'python':'python3';for(const[dir,requirements]of[['.venv','requirements-delivery.txt'],['.venv-rig','requirements-rig-test.txt']]){for(const[exe,args]of[[py,['-m','venv',dir]],[join(dir,process.platform==='win32'?'Scripts/python.exe':'bin/python'),['-m','pip','install','-r',requirements]]]){const r=spawnSync(exe,args,{stdio:'inherit'});if(r.error){console.error(r.error.message);process.exit(1)}if(r.status!==0)process.exit(r.status===null?1:r.status)}}\"",
+      "npm ci --ignore-scripts --prefix tools/rig"
+    ],
+    "teardown": "echo \"Setup starts no persistent services; Paseo handles worktree removal.\""
+  },
+  "scripts": {
+    "diff-check": {
+      "command": "git diff --check"
+    }
+  }
+}