Add a micro-VM variant of the sandbox demo

cmd/ate-setup/internal/demos/all/all.go

@@ -31,4 +31,5 @@ import (
 	_ "github.com/agent-substrate/substrate/cmd/ate-setup/internal/demos/multitemplate"
 	_ "github.com/agent-substrate/substrate/cmd/ate-setup/internal/demos/parking"
 	_ "github.com/agent-substrate/substrate/cmd/ate-setup/internal/demos/sandbox"
+	_ "github.com/agent-substrate/substrate/cmd/ate-setup/internal/demos/sandboxmicrovm"
 )

cmd/ate-setup/internal/demos/sandboxmicrovm/sandboxmicrovm.go

@@ -0,0 +1,43 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package sandboxmicrovm installs the micro-VM variant of the sandbox demo.
+//
+// It needs the cluster-wide `microvm` SandboxConfig that
+// hack/install-microvm-deps.sh --install creates.
+package sandboxmicrovm
+
+import (
+	"github.com/agent-substrate/substrate/cmd/ate-setup/internal/demos"
+	"github.com/agent-substrate/substrate/cmd/ate-setup/internal/steps"
+	"github.com/agent-substrate/substrate/internal/resources"
+)
+
+// namespace is the pool's k8s namespace; it doubles as the atespace holding
+// the demo's ActorTemplate.
+const namespace = "ate-demo-sandbox-microvm"
+
+func init() {
+	demos.Register(&demos.Substrate{
+		DemoName:           "demo-sandbox-microvm",
+		Short:              "The sandbox demo on micro-VM workers (needs hack/install-microvm-deps.sh --install)",
+		WorkerPoolManifest: "demos/sandbox/sandbox-microvm.yaml.tmpl",
+		Deployments:        []steps.TemplateRef{{Atespace: namespace, Name: "sandbox-microvm"}},
+		Templates: []demos.SubstrateTemplate{{
+			Manifest: "demos/sandbox/sandbox-microvm-template.yaml.tmpl",
+			Ref:      resources.ActorTemplateRef{Atespace: namespace, Name: "sandbox-microvm"},
+		}},
+		GoldenTimeout: demos.MicroVMGoldenTimeout,
+	})
+}

demos/sandbox/README.md

@@ -45,6 +45,25 @@ Inspect the template with:
 kubectl ate get actor-template sandbox-template -a ate-demo-sandbox
 ```
 
+#### Micro-VM variant
+
+The default template runs on gVisor. Where gVisor cannot start a sandbox on the
+host kernel, deploy the micro-VM variant instead:
+
+```bash
+./hack/install-ate.sh --deploy-demo-sandbox-microvm
+```
+
+It installs the same server into the `ate-demo-sandbox-microvm` namespace and
+atespace, with the pool's workers on micro-VM (`ateom-microvm`) and the template
+naming the cluster-wide `microvm` SandboxConfig. That config comes from
+`hack/install-microvm-deps.sh --install`, which has to have run first. The
+sandbox class is the only difference: the client, the commands, and the
+suspend/resume behavior are the same, so substitute
+
+- `--atespace=ate-demo-sandbox-microvm` in the client invocation below,
+- `-a ate-demo-sandbox-microvm` where the actor commands name the atespace.
+
 ### 2. Create a Sandbox Actor
 
 Create the sandbox actor in the demo's atespace with a chosen name (e.g., `my-sandbox-1`) — `--template` names the template, resolved in the actor's atespace:
@@ -111,3 +130,9 @@ To remove the sandbox demo resources (actors, template, atespace, workerpool, an
 ```bash
 ./hack/install-ate.sh --delete-demo-sandbox
 ```
+
+The micro-VM variant is removed the same way:
+
+```bash
+./hack/install-ate.sh --delete-demo-sandbox-microvm
+```

demos/sandbox/sandbox-microvm-template.yaml.tmpl

@@ -0,0 +1,47 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# ActorTemplate (protojson-shaped ateapipb.ActorTemplate) for the micro-VM
+# sandbox demo. Applied with `kubectl ate create actor-template -f -` after
+# `ko resolve` replaces the ko:// image reference; the
+# ate-demo-sandbox-microvm atespace must exist.
+metadata:
+  atespace: ate-demo-sandbox-microvm
+  name: sandbox-microvm
+workerSelector:
+  matchLabels:
+    workload: sandbox-microvm
+containers:
+- name: sandbox
+  image: ko://github.com/agent-substrate/substrate/demos/sandbox
+  env:
+  - name: PORT
+    value: "80"
+# Sandbox size: vCPUs + guest RAM at (or below) the pool's per-worker capacity,
+# leaving VMM-reserve headroom under the worker memory limit (see
+# internal/sizing). Quantities are strings in the proto.
+resources:
+  limits:
+  - name: cpu
+    quantity: "1"
+  - name: memory
+    quantity: 512Mi
+snapshotConfig:
+  # MEMORY, matching the gVisor variant: the sandbox preserves live process
+  # state across a suspend, so a resume continues the same shell session.
+  preferredFidelity: SNAPSHOT_FIDELITY_MEMORY
+  storageLocation: gs://${BUCKET_NAME}/ate-demo-sandbox-microvm/
+sandboxConfig:
+  sandboxClass: SANDBOX_CLASS_MICROVM
+  configName: microvm

demos/sandbox/sandbox-microvm.yaml.tmpl

@@ -0,0 +1,64 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Worker pool for the micro-VM (kata + cloud-hypervisor) variant of the sandbox
+# demo. The ActorTemplate is not a CRD: it lives in
+# sandbox-microvm-template.yaml.tmpl and is created through the ate API with
+# `kubectl ate create actor-template`. The cluster-wide `microvm`
+# SandboxConfig referenced by the pool is installed by
+# hack/install-microvm-deps.sh
+
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: ate-demo-sandbox-microvm
+
+---
+
+apiVersion: ate.dev/v1alpha1
+kind: WorkerPool
+metadata:
+  name: sandbox-microvm
+  namespace: ate-demo-sandbox-microvm
+  labels:
+    workload: sandbox-microvm
+spec:
+  # Two workers: one for the sandbox actor, one spare for the golden actor the
+  # template reconciler runs while building the golden snapshot.
+  replicas: 2
+  sandboxClasses:
+  - name: microvm
+    configRef:
+      name: microvm
+  workerImage: ko://github.com/agent-substrate/substrate/cmd/ateom-microvm
+  template:
+    # Per-worker resources: these size the worker POD and advertise its
+    # scheduling capacity (the per-actor ceiling). The micro-VM sandbox itself is
+    # sized by the ActorTemplate's resources in
+    # sandbox-microvm-template.yaml.tmpl, not by these; keep the actor memory
+    # below this limit so the VMM reserve fits (see internal/sizing).
+    #
+    # Capacity comes from the limits (workerCapacity reads limits only), while the
+    # kube-scheduler packs nodes by the requests — so the CPU request is set well
+    # below the limit to keep the pool placeable on a small node (a single kind
+    # node in CI, shared with the other demo pools) without changing what an actor
+    # is allowed to use. Memory is not compressible, so its request matches the
+    # limit: the guest RAM plus the VMM reserve has to be really there.
+    resources:
+      limits:
+        cpu: "1"
+        memory: 1Gi
+      requests:
+        cpu: 250m
+        memory: 1Gi

hack/install-ate.sh

@@ -47,6 +47,7 @@ ATE_DEMOS=(
   demo-egress-microvm
   demo-jupyter
   demo-sandbox
+  demo-sandbox-microvm
   demo-claude-code-multiplex
   demo-multi-template
   demo-parking
@@ -60,7 +61,7 @@ demo_usage() {
       echo "  --deploy-demo-counter-with-external-volume    Deploy demo-counter with external volume validation"
       echo "                                                (STORAGE_CLASS names the class; it otherwise follows --setup-csi)"
       ;;
-    demo-counter-microvm|demo-egress-microvm)
+    demo-counter-microvm|demo-egress-microvm|demo-sandbox-microvm)
       echo "  Needs hack/install-microvm-deps.sh --install to have run (cluster-wide microvm SandboxConfig)."
       ;;
     demo-claude-code-multiplex)