diff --git a/backend/scripts/verify-workspace-descriptor-files.mjs b/backend/scripts/verify-workspace-descriptor-files.mjs
index 1648b637..35b78259 100755
--- a/backend/scripts/verify-workspace-descriptor-files.mjs
+++ b/backend/scripts/verify-workspace-descriptor-files.mjs
@@ -40,7 +40,7 @@ const reviewedExpandableBlocks = new Map([
   ]],
   ["scripts/unified-deployment-smoke.sh", [
     { sha256: "ca0c17d9ff8dc0fbe018fc1c5510eb33bc667a936fbe44a9be2d311390576825", rationale: "Generates reviewed Task 13 runtime configuration." },
-    { sha256: "edf4d9c35b0328ec1549e5a529eceb1044434850b85786091ae8a0c6620b39d7", rationale: "Generates the reviewed local Task 13 Compose override." },
+    { sha256: "714d44082040affc28114a6a462164e3165c5c9fb2eefcd27f764c8dac7e161e", rationale: "Generates the reviewed local Task 13 Compose override." },
     { sha256: "c556f7d910d0788e219b042957e6b307cb9925b43920c680535d0d3a6dcbdb25", rationale: "Generates the reviewed local Task 13 installation descriptor." },
     { sha256: "c0078c68bd42a8668fbcb849888531e5e56109579df1ff96140a9e91b1efea56", rationale: "Generates the reviewed server Task 13 Compose override." },
     { sha256: "b34a2b4ffaa72e01efb64a7a28b13513527538d837b2f35b6ca5fb3dbdb2d5dc", rationale: "Generates the reviewed server Task 13 installation descriptor." },
diff --git a/scripts/unified-deployment-smoke.sh b/scripts/unified-deployment-smoke.sh
index e75b87fd..227cd3bd 100755
--- a/scripts/unified-deployment-smoke.sh
+++ b/scripts/unified-deployment-smoke.sh
@@ -502,7 +502,7 @@ services:
       - workspace-registry:/data/workspace-registry
       - workspace-secrets:/data/workspace-secrets
       - sessions:/data/sessions
-      - $TASK13_AUTH_ROOT:/run/thothii-auth:ro
+      - auth-runtime:/run/thothii-auth:ro
       - auth-state:/data/auth
       - $TASK13_SESSION_RUNTIME_PASSWORD:/run/secrets/task13-runtime-password:ro
       - $TASK13_REMOTE:/fixtures/remote.git:ro
@@ -547,6 +547,9 @@ volumes:
   auth-state:
     labels:
       io.thothii.task13.run: "$TASK13_RUN_ID"
+  auth-runtime:
+    labels:
+      io.thothii.task13.run: "$TASK13_RUN_ID"
   qdrant-data:
     labels:
       io.thothii.task13.run: "$TASK13_RUN_ID"
@@ -913,10 +916,39 @@ task13_configure_server_oidc_authentication() {
     --authentik-base-url "https://task13-fake-oidc:9443" --user-group task13-users --admin-group task13-admins
 }
 
+task13_prepare_local_auth_runtime() {
+  local owner_label
+  owner_label="$(docker volume inspect --format '{{ index .Labels "io.thothii.task13.run" }}' \
+    "$TASK13_AUTH_RUNTIME_VOLUME")"
+  [[ "$owner_label" == "$TASK13_RUN_ID" ]] \
+    || task13_fail "local authentication runtime volume lacks the Task 13 run label"
+  task13_run_logged "project local authentication for the core runtime" docker run --rm \
+    --name "$TASK13_AUTH_PROJECTION_CONTAINER" \
+    --label "io.thothii.task13.run=$TASK13_RUN_ID" \
+    --user 0:0 \
+    --entrypoint sh \
+    --volume "$TASK13_AUTH_ROOT:/source:ro" \
+    --volume "$TASK13_AUTH_RUNTIME_VOLUME:/target" \
+    "$TASK13_CORE_IMAGE" -ceu '
+      test -f /source/auth.yaml && test ! -L /source/auth.yaml
+      test -f /source/users.yaml && test ! -L /source/users.yaml
+      test -z "$(find /target -mindepth 1 -maxdepth 1 -print -quit)"
+      cp /source/auth.yaml /source/users.yaml /target/
+      chown 10001:10001 /target /target/auth.yaml /target/users.yaml
+      chmod 0700 /target
+      chmod 0600 /target/auth.yaml /target/users.yaml
+      test "$(stat -c "%u:%g:%a" /target)" = 10001:10001:700
+      test "$(stat -c "%u:%g:%a" /target/auth.yaml)" = 10001:10001:600
+      test "$(stat -c "%u:%g:%a" /target/users.yaml)" = 10001:10001:600
+    '
+}
+
 task13_start_stack() {
   printf '== Build and start isolated local Compose distribution ==\n'
   task13_assert_rendered_contract
   task13_compose_logged "build local Compose images" build --pull
+  task13_compose_logged "create local core authentication runtime" create --no-deps core
+  task13_prepare_local_auth_runtime
   task13_compose_start_logged "start local Compose distribution" up --detach --wait --wait-timeout 120
   TASK13_NETWORK="$(docker network ls \
     --filter "label=com.docker.compose.project=$TASK13_PROJECT" \
@@ -1762,6 +1794,7 @@ task13_cleanup() {
     tail -n 200 "$TASK13_LOG" | task13_sanitize >&2
   fi
   task13_remove_labeled_container "${TASK13_BAD_CANDIDATE_CONTAINER:-}" || cleanup_rc=1
+  task13_remove_labeled_container "${TASK13_AUTH_PROJECTION_CONTAINER:-}" || cleanup_rc=1
   task13_remove_labeled_container "${TASK13_LLM_CONTAINER:-}" || cleanup_rc=1
   task13_remove_labeled_container "${TASK13_OIDC_CONTAINER:-}" || cleanup_rc=1
   if [[ -n "${TASK13_PROJECT:-}" && -n "${TASK13_ROOT:-}" && -f "${TASK13_OVERRIDE:-}" ]]; then
@@ -2323,11 +2356,16 @@ task13_self_test_registry_fingerprint() {
 
 task13_self_test_source_contract() {
   local root host_network push_command registry_function workflow uses_count pinned_uses_count
+  local auth_runtime_mount auth_root_mount auth_projection auth_runtime_owner
   root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd -P)"
   workflow="$root/.github/workflows/deployment.yml"
   host_network='--network'' host'
   push_command='docker image ''push'
   registry_function='task13_start_''registry'
+  auth_runtime_mount='auth-runtime:/run/thothii-''auth:ro'
+  auth_root_mount='$TASK13_AUTH_''ROOT:/run/thothii-auth:ro'
+  auth_projection='task13_prepare_local_auth_''runtime'
+  auth_runtime_owner='chown 10001:''10001 /target'
   if rg -n 'docker[[:space:]]+(system[[:space:]]+)?prune' \
     "$root/scripts/unified-deployment-smoke.sh" \
     "$root/scripts/tht-update-smoke.sh" \
@@ -2340,6 +2378,15 @@ task13_self_test_source_contract() {
     || grep -Fq -- "$registry_function" "$root/scripts/unified-deployment-smoke.sh"; then
     task13_fail "the rollback fixture must not depend on a daemon-to-host local image registry"
   fi
+  grep -Fq -- "$auth_runtime_mount" "$root/scripts/unified-deployment-smoke.sh" \
+    || task13_fail "the local smoke must mount a Compose-owned authentication runtime volume"
+  ! grep -Fq -- "$auth_root_mount" "$root/scripts/unified-deployment-smoke.sh" \
+    || task13_fail "the local smoke must not bind host-owned authentication into the core"
+  [[ "$(grep -Ec "^${auth_projection}\\(\\)|^[[:space:]]+${auth_projection}$" \
+    "$root/scripts/unified-deployment-smoke.sh")" -eq 2 ]] \
+    || task13_fail "the local authentication runtime projection must be defined and invoked once"
+  grep -Fq -- "$auth_runtime_owner" "$root/scripts/unified-deployment-smoke.sh" \
+    || task13_fail "the local authentication runtime projection must enforce the core UID"
   grep -Eq '^TASK13_BAD_CANDIDATE_IMAGE="[^"[:space:]]+@sha256:[0-9a-f]{64}"$' \
     "$root/scripts/unified-deployment-smoke.sh" \
     || task13_fail "the bad rollback candidate must be an immutable digest reference"
@@ -2491,6 +2538,8 @@ task13_initialize() {
   TASK13_SECRETS="$TASK13_TMP/thothii.secrets"
   TASK13_AUTH_ROOT="$TASK13_TMP/auth"
   TASK13_AUTH_PASSWORD_FILE="$TASK13_TMP/local-auth-password"
+  TASK13_AUTH_RUNTIME_VOLUME="${TASK13_PROJECT}_auth-runtime"
+  TASK13_AUTH_PROJECTION_CONTAINER="$TASK13_PROJECT-auth-projection"
   TASK13_AUTH_ADMIN=task13-admin
   TASK13_AUTH_PASSWORD="task13-auth-$TASK13_RUN_ID"
   TASK13_OIDC_CLIENT_SECRET="task13-oidc-client-$TASK13_RUN_ID"