diff --git a/.agents/skills/dev-branch/SKILL.md b/.agents/skills/dev-branch/SKILL.md
new file mode 100644
index 000000000..7668f5ebe
--- /dev/null
+++ b/.agents/skills/dev-branch/SKILL.md
@@ -0,0 +1,106 @@
+---
+name: dev-branch
+description: Parallel development using hack/dev-branch.sh to isolate worktrees and Kind test clusters per feature.
+---
+
+# Multi-Agent Parallel Development with `hack/dev-branch.sh`
+
+This skill provides workflow guidance for executing concurrent development tasks,
+working on separate features within the `agent-substrate/substrate` repository.
+
+By isolating each feature inside its own **Git worktree** and **Kind Kubernetes
+cluster**, multiple agents can build, test, and debug features in parallel
+without step-on or port/cluster resource contention.
+
+---
+
+## Architecture & Principles
+
+| Resource | Isolation Strategy | Purpose |
+| :--- | :--- | :--- |
+| **Source Code** | Git Worktree (`.worktrees/<branch>`) | Independent code branch & checkout per agent |
+| **Kubernetes Cluster** | Kind Cluster (`kind-dev-<branch>`) | Dedicated cluster running `ate-system` per agent |
+| **Container Registry** | Shared Docker Registry (`kind-registry:5001`) | Centralized image storage shared safely across clusters |
+| **Environment Vars** | `.dev-env.sh` / `dev-branch.sh exec` | Auto-routes `kubectl` & E2E tests to the correct cluster |
+
+---
+
+## Step-by-Step Workflow
+
+### 1. Provision Environment
+
+When starting a feature or delegating a task to a subagent, provision an
+isolated environment:
+
+```bash
+./hack/dev-branch.sh setup <branch-name>
+```
+
+- **Branch Name Format**: Use distinct, descriptive names (e.g.,
+  `agent-router-fix`, `agent-valkey-backup`).
+- **Path**: Created automatically under `.worktrees/<sanitized-branch>`.
+
+### 2. Spawning Subagents (Parallel Execution)
+
+When spawning parallel subagents using `invoke_subagent`:
+- Pass the target worktree path (`.worktrees/<branch-name>`) in the prompt.
+- Instruct subagents to use `./hack/dev-branch.sh exec <branch-name> --
+  <command>` for running commands against their specific environment.
+
+Example prompt fragment:
+
+> You are assigned to implement feature X in branch `agent-feature-x`.
+> Work inside the directory `.worktrees/agent-feature-x`.
+> Run tests using `./hack/dev-branch.sh exec agent-feature-x -- ./hack/run-e2e-kind.sh`.
+
+### 3. Executing Commands & Testing
+
+Instead of manually setting environment variables in every subshell, use `exec`:
+
+```bash
+# Run unit tests inside the worktree
+./hack/dev-branch.sh exec <branch-name> -- go test ./...
+
+# Run E2E tests against the branch's dedicated Kind cluster
+./hack/dev-branch.sh exec <branch-name> -- ./hack/run-e2e-kind.sh
+```
+
+Alternatively, `eval` the environment in the subshell:
+```bash
+cd .worktrees/<branch-name>
+eval "$(/path/to/main/hack/dev-branch.sh env <branch-name>)"
+./hack/run-e2e-kind.sh
+```
+
+### 4. Avoiding Resource & Port Conflicts
+
+- **Kubernetes Contexts**: Contexts are automatically isolated per cluster
+  (`kind-kind-dev-<branch-name>`).
+- **Port Forwarding**: When port-forwarding services (e.g. `atenet-router`),
+  select dynamic host ports or unique ports per agent to avoid collisions:
+
+  ```bash
+  # Use random available host port
+  kubectl --context kind-kind-dev-<branch-name> port-forward -n ate-system svc/atenet-router :80
+  ```
+
+### 5. Listing Active Environments
+
+Check all active parallel environments:
+
+```bash
+./hack/dev-branch.sh list
+```
+
+### 6. Teardown
+
+When work on a feature is finished and merged/submitted:
+
+```bash
+./hack/dev-branch.sh teardown <branch-name>
+```
+
+- Deletes the `kind-dev-<branch-name>` cluster.
+- Removes the `.worktrees/<branch-name>` directory.
+- Preserves the shared `kind-registry` container if other agents' Kind clusters
+  are still active.
diff --git a/hack/delete-kind-cluster.sh b/hack/delete-kind-cluster.sh
index fe4aec4ff..fb6d6deaf 100755
--- a/hack/delete-kind-cluster.sh
+++ b/hack/delete-kind-cluster.sh
@@ -40,8 +40,13 @@ fi
 if [ "${reg_exists}" == true ]; then
   reg_created_by="$(docker inspect --format '{{index .Config.Labels "created-by"}}' "${reg_name}" 2>/dev/null)"
   if [ "${reg_created_by}" == "agent-substrate" ]; then
-    echo "Deleting registry container '${reg_name}' (created by us)..."
-    docker rm -f "${reg_name}" || true
+    remaining_clusters="$("${ROOT}"/hack/kind.sh get clusters 2>/dev/null | grep -v 'No kind clusters found' | grep -v '^$' || true)"
+    if [ -z "${remaining_clusters}" ]; then
+      echo "No remaining Kind clusters found. Deleting registry container '${reg_name}'..."
+      docker rm -f "${reg_name}" || true
+    else
+      echo "Other Kind clusters are still running, keeping registry container '${reg_name}'."
+    fi
   else
     echo "Registry container '${reg_name}' was not created by us (${reg_created_by}), leaving it running."
   fi
diff --git a/hack/dev-branch.sh b/hack/dev-branch.sh
new file mode 100755
index 000000000..2d40210ae
--- /dev/null
+++ b/hack/dev-branch.sh
@@ -0,0 +1,278 @@
+#!/usr/bin/env bash
+
+# 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.
+
+set -o errexit -o nounset -o pipefail
+
+GIT_COMMON_DIR="$(git rev-parse --git-common-dir)"
+MAIN_ROOT="$(cd "${GIT_COMMON_DIR}/.." && pwd)"
+cd "${MAIN_ROOT}"
+
+sanitize_name() {
+  local raw_name="$1"
+  local cleaned
+  cleaned="$(echo "${raw_name}" | tr '[:upper:]' '[:lower:]' | sed -E 's/[^a-z0-9-]+/-/g' | sed -E 's/^-+|-+$//g')"
+  if [[ -z "${cleaned}" ]]; then
+    cleaned="dev"
+  fi
+  echo "${cleaned}"
+}
+
+show_help() {
+  cat <<EOF
+Usage: $0 <command> [args]
+
+Manage self-contained development environments (Git worktree + Kind cluster).
+
+Commands:
+  setup <branch-name> [worktree-path]
+      Creates a Git worktree, provisions an isolated Kind cluster, deploys the
+      Substrate control plane, and writes a .dev-env.sh file.
+
+  teardown <branch-name> [worktree-path]
+      Deletes the isolated Kind cluster and removes the Git worktree.
+
+  env <branch-name>
+      Outputs environment variable export statements for testing against the branch's
+      Kind cluster. Usage: eval "\$($0 env <branch-name>)"
+
+  exec <branch-name> -- <command...>
+      Executes the command inside the branch's worktree directory with environment
+      variables set for its Kind cluster.
+
+  list
+      Lists active Git worktrees and Kind clusters.
+
+  help, -h, --help
+      Displays this help message.
+
+Examples:
+  $0 setup feature-router
+  $0 exec feature-router -- hack/run-e2e-kind.sh
+  $0 teardown feature-router
+EOF
+}
+
+setup_env() {
+  local branch="${1:-}"
+  local target_path="${2:-}"
+
+  if [[ -z "${branch}" ]]; then
+    echo "Error: Branch name required for setup." >&2
+    echo "Usage: $0 setup <branch-name> [worktree-path]" >&2
+    exit 1
+  fi
+
+  local s_name
+  s_name="$(sanitize_name "${branch}")"
+  local cluster_name="kind-dev-${s_name}"
+
+  if [[ -z "${target_path}" ]]; then
+    target_path="${MAIN_ROOT}/.worktrees/${s_name}"
+  fi
+
+  echo "==> Setting up development environment for branch '${branch}'..."
+  echo "    Worktree path: ${target_path}"
+  echo "    Kind cluster:  ${cluster_name}"
+
+  mkdir -p "$(dirname "${target_path}")"
+  if [[ -d "${target_path}" ]]; then
+    echo "    Worktree directory '${target_path}' already exists."
+  else
+    if git rev-parse --verify "${branch}" >/dev/null 2>&1; then
+      echo "    Adding worktree for existing branch '${branch}'..."
+      git worktree add "${target_path}" "${branch}"
+    elif git rev-parse --verify "origin/${branch}" >/dev/null 2>&1; then
+      echo "    Adding worktree tracking 'origin/${branch}'..."
+      git worktree add -b "${branch}" "${target_path}" "origin/${branch}"
+    else
+      echo "    Creating new branch '${branch}' and adding worktree..."
+      git worktree add -b "${branch}" "${target_path}" HEAD
+    fi
+  fi
+
+  echo "==> Provisioning Kind cluster '${cluster_name}'..."
+  KIND_CLUSTER_NAME="${cluster_name}" "${MAIN_ROOT}/hack/create-kind-cluster.sh"
+
+  echo "==> Deploying Agent Substrate control plane to '${cluster_name}'..."
+  KIND_CLUSTER_NAME="${cluster_name}" "${MAIN_ROOT}/hack/install-ate-kind.sh" --deploy-ate-system
+
+  echo "==> Writing environment configuration file '${target_path}/.dev-env.sh'..."
+  cat <<EOF > "${target_path}/.dev-env.sh"
+# Environment configuration for dev branch '${branch}'
+export NO_DEV_ENV="true"
+export KIND_CLUSTER_NAME="${cluster_name}"
+export KUBECTL_CONTEXT="kind-${cluster_name}"
+export KO_DOCKER_REPO="localhost:5001"
+export BUCKET_NAME="ate-snapshots"
+EOF
+
+  echo ""
+  echo "========================================================================="
+  echo "Development environment setup complete!"
+  echo ""
+  echo "To start working in this environment:"
+  echo "  cd ${target_path}"
+  echo "  eval \"\$(${MAIN_ROOT}/hack/dev-branch.sh env ${branch})\""
+  echo "  # or: source .dev-env.sh"
+  echo ""
+  echo "To run E2E tests against this isolated environment:"
+  echo "  ${MAIN_ROOT}/hack/dev-branch.sh exec ${branch} -- ./hack/run-e2e-kind.sh"
+  echo ""
+  echo "To teardown this environment when finished:"
+  echo "  ${MAIN_ROOT}/hack/dev-branch.sh teardown ${branch} ${target_path}"
+  echo "========================================================================="
+}
+
+teardown_env() {
+  local branch="${1:-}"
+  local target_path="${2:-}"
+
+  if [[ -z "${branch}" ]]; then
+    echo "Error: Branch name required for teardown." >&2
+    echo "Usage: $0 teardown <branch-name> [worktree-path]" >&2
+    exit 1
+  fi
+
+  local s_name
+  s_name="$(sanitize_name "${branch}")"
+  local cluster_name="kind-dev-${s_name}"
+
+  if [[ -z "${target_path}" ]]; then
+    target_path="${MAIN_ROOT}/.worktrees/${s_name}"
+  fi
+
+  echo "==> Tearing down development environment for branch '${branch}'..."
+
+  echo "==> Deleting Kind cluster '${cluster_name}'..."
+  KIND_CLUSTER_NAME="${cluster_name}" "${MAIN_ROOT}/hack/delete-kind-cluster.sh" || true
+
+  if git worktree list | grep -q "${target_path}"; then
+    echo "==> Removing Git worktree at '${target_path}'..."
+    git worktree remove --force "${target_path}" || true
+  elif [[ -d "${target_path}" ]]; then
+    echo "==> Removing directory '${target_path}'..."
+    rm -rf "${target_path}"
+  fi
+
+  echo "Teardown complete for '${branch}'."
+}
+
+print_env() {
+  local branch="${1:-}"
+
+  if [[ -z "${branch}" ]]; then
+    echo "# Error: Branch name required for env." >&2
+    echo "# Usage: eval \"\$($0 env <branch-name>)\"" >&2
+    exit 1
+  fi
+
+  local s_name
+  s_name="$(sanitize_name "${branch}")"
+  local cluster_name="kind-dev-${s_name}"
+
+  cat <<EOF
+export NO_DEV_ENV="true"
+export KIND_CLUSTER_NAME="${cluster_name}"
+export KUBECTL_CONTEXT="kind-${cluster_name}"
+export KO_DOCKER_REPO="localhost:5001"
+export BUCKET_NAME="ate-snapshots"
+EOF
+}
+
+exec_env() {
+  local branch="${1:-}"
+  if [[ -z "${branch}" ]]; then
+    echo "Error: Branch name required for exec." >&2
+    echo "Usage: $0 exec <branch-name> -- <command...>" >&2
+    exit 1
+  fi
+  shift
+
+  if [[ "$#" -gt 0 && "$1" == "--" ]]; then
+    shift
+  fi
+
+  if [[ "$#" -eq 0 ]]; then
+    echo "Error: No command specified to execute." >&2
+    echo "Usage: $0 exec <branch-name> -- <command...>" >&2
+    exit 1
+  fi
+
+  local s_name
+  s_name="$(sanitize_name "${branch}")"
+  local cluster_name="kind-dev-${s_name}"
+  local target_path="${MAIN_ROOT}/.worktrees/${s_name}"
+
+  if [[ ! -d "${target_path}" ]]; then
+    echo "Error: Worktree directory '${target_path}' does not exist. Run setup first." >&2
+    exit 1
+  fi
+
+  export NO_DEV_ENV="true"
+  export KIND_CLUSTER_NAME="${cluster_name}"
+  export KUBECTL_CONTEXT="kind-${cluster_name}"
+  export KO_DOCKER_REPO="localhost:5001"
+  export BUCKET_NAME="ate-snapshots"
+
+  cd "${target_path}"
+  exec "$@"
+}
+
+list_envs() {
+  echo "Active Git Worktrees:"
+  git worktree list
+  echo ""
+  echo "Active Kind Clusters:"
+  "${MAIN_ROOT}/hack/kind.sh" get clusters 2>/dev/null || echo "No kind clusters found."
+}
+
+main() {
+  if [[ "$#" -eq 0 ]]; then
+    show_help
+    exit 0
+  fi
+
+  local cmd="$1"
+  shift
+
+  case "${cmd}" in
+    setup|create)
+      setup_env "$@"
+      ;;
+    teardown|delete|destroy)
+      teardown_env "$@"
+      ;;
+    env)
+      print_env "$@"
+      ;;
+    exec)
+      exec_env "$@"
+      ;;
+    list|status)
+      list_envs "$@"
+      ;;
+    help|-h|--help)
+      show_help
+      ;;
+    *)
+      echo "Error: Unknown command '${cmd}'" >&2
+      show_help
+      exit 1
+      ;;
+  esac
+}
+
+main "$@"