diff --git a/pack/.post_operation/20260920_vllm_install_router/cuda/Dockerfile b/pack/.post_operation/20260920_vllm_install_router/cuda/Dockerfile
new file mode 100644
index 0000000..4aa41d5
--- /dev/null
+++ b/pack/.post_operation/20260920_vllm_install_router/cuda/Dockerfile
@@ -0,0 +1,61 @@
+ARG CMAKE_MAX_JOBS
+ARG CUDA_VERSION=12.9
+ARG VLLM_VERSION=0.27.1
+ARG VLLM_ROUTER_VERSION=0.1.15
+
+FROM gpustack/runner:cuda${CUDA_VERSION}-vllm${VLLM_VERSION} AS vllm
+SHELL ["/bin/bash", "-eo", "pipefail", "-c"]
+
+ARG TARGETPLATFORM
+ARG TARGETOS
+ARG TARGETARCH
+
+## Install vLLM Router
+##
+## `pack/cuda/Dockerfile.vllm` only gained the router after 0.27.1 was cut, so the released 0.27.1
+## images carry none of it: a disaggregated group deployed on them has no router to run, and either
+## falls back to an engine example script (no metrics, no circuit breaker, no health check) or does
+## not start at all. 0.29.0 already ships it, which is why 0.27.1 is the only CUDA runner here.
+##
+## Pinned to the same 0.1.15 the recipe installs, so that a 0.27.1 image and a 0.29.0 image render
+## the same router. The wheel is prebuilt for both aarch64 and x86_64, and it depends on nothing
+## but pure-Python web packages (fastapi, uvicorn, aiohttp, orjson, requests, setproctitle) -- it
+## does not depend on vLLM, so this install cannot move the torch/vLLM stack already in the image.
+
+ARG VLLM_ROUTER_VERSION
+
+RUN <<EOF
+    # vLLM Router
+
+    uv pip install \
+        vllm-router==${VLLM_ROUTER_VERSION}
+
+    # Fail the build rather than ship an image whose router is missing: the
+    # alternative surfaces as a container that exits at deploy time, one
+    # layer away from anything that explains it.
+    command -v vllm-router >/dev/null
+
+    # Review
+    uv pip tree
+
+    # Cleanup
+    rm -rf /var/tmp/* \
+        && rm -rf /tmp/*
+EOF
+
+## Probe Dependencies
+
+ARG DEPENDENCY_PACKAGES=""
+RUN --mount=type=bind,from=shared,source=probe_dependencies.sh,target=/tmp/probe_dependencies.sh \
+    DEPENDENCY_PACKAGES="${DEPENDENCY_PACKAGES}" bash /tmp/probe_dependencies.sh
+
+## Entrypoint
+
+WORKDIR /
+ENTRYPOINT [ "tini", "--" ]
+
+## Export Dependencies
+
+FROM scratch AS vllm-deps
+
+COPY --from=vllm /etc/gpustack-runner/dependencies.json /
diff --git a/pack/.post_operation/20260920_vllm_install_router/matrix.yaml b/pack/.post_operation/20260920_vllm_install_router/matrix.yaml
new file mode 100644
index 0000000..73c6959
--- /dev/null
+++ b/pack/.post_operation/20260920_vllm_install_router/matrix.yaml
@@ -0,0 +1,32 @@
+rules:
+
+  # CUDA 0.27.1 only, and deliberately so.
+  #
+  # The router install lives in `pack/cuda/Dockerfile.vllm` and `pack/cann/Dockerfile.vllm` -- the
+  # two recipes GPUStack renders a PD mode for. Of the released images that miss it:
+  #
+  #   - cuda 0.27.1 is no longer in `pack/matrix.yaml` (CUDA stands at 0.29.0, which already ships
+  #     the router), so rewriting the tag here is the only way to put a router into it.
+  #   - cann 0.23.0 is still exactly what `pack/matrix.yaml` builds, and the recipe already carries
+  #     the router, so a normal `for_release` pack of backend `cann` rebuilds those four variants
+  #     with it. That is a plain release rather than a mutation, so it does not belong here.
+  #   - rocm never installed a router at all; its 0.29.0 image has none either, and patching only
+  #     0.27.1 would leave the newer image the odd one out.
+
+  ## Packed NVIDIA CUDA 13.0.
+  ##
+  - backend: "cuda"
+    services:
+      - "vllm"
+    args:
+      - "CUDA_VERSION=13.0"
+      - "VLLM_VERSION=0.27.1"
+
+  ## Packed NVIDIA CUDA 12.9.
+  ##
+  - backend: "cuda"
+    services:
+      - "vllm"
+    args:
+      - "CUDA_VERSION=12.9"
+      - "VLLM_VERSION=0.27.1"
diff --git a/pack/.post_operation/README.md b/pack/.post_operation/README.md
index ce7bd43..ac1e69a 100644
--- a/pack/.post_operation/README.md
+++ b/pack/.post_operation/README.md
@@ -101,3 +101,4 @@ mutated stay as they were until the next release rebuilds those images.
 - [x] 2026-03-03: Fix malformed ARM64 image for vLLM 0.15.1 of CUDA released images.
 - [x] 2026-09-01: Pin `numpy` to 1.26.4 and remove CUDA-only NIXL EP packages for vLLM 0.18.1 of DTK 26.04 released images.
 - [x] 2026-09-16: Patch vLLM 0.24.0/0.25.1/0.27.1/0.29.0 of CUDA/ROCm released images to fix mooncake prom metrics issue.
+- [ ] 2026-09-20: Install `vllm-router` package for vLLM 0.27.1 of CUDA released images.