diff --git a/.github/workflows/cluster-tests.yml b/.github/workflows/cluster-tests.yml
new file mode 100644
index 0000000..544cd5b
--- /dev/null
+++ b/.github/workflows/cluster-tests.yml
@@ -0,0 +1,45 @@
+# Workflow to test latest climate-aware-task-scheduler release against ephemeral Slurm cluster
+name: cluster-tests
+
+on:
+  push:
+    branches: [ main ]
+    paths:
+    - '.github/workflows/cluster-tests.yml'
+    - 'cluster/**'
+    - 'cats/**.py'
+    - 'pyproject.toml'
+    - '!cluster/README.md'
+  pull_request:
+    branches: [ main ]
+    paths:
+    - '.github/workflows/cluster-tests.yml'
+    - 'cluster/**'
+    - 'cats/**.py'
+    - 'pyproject.toml'
+    - '!cluster/README.md'
+  workflow_dispatch:
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: read
+    steps:
+    - uses: actions/checkout@v4
+    - name: Log in to GHCR
+      uses: docker/login-action@v3
+      with:
+        registry: ghcr.io
+        username: ${{ github.actor }}
+        password: ${{ secrets.GITHUB_TOKEN }}
+    - name: Start slurm cluster and install CATS
+      run: |
+        ./cluster/start.sh
+        ./cluster/install_cats.sh
+    - name: Run tests
+      run: |
+        sleep 30  # wait for cluster to come up
+        ./cluster/tests.sh
diff --git a/cluster/README.md b/cluster/README.md
new file mode 100644
index 0000000..d1d119d
--- /dev/null
+++ b/cluster/README.md
@@ -0,0 +1,46 @@
+# Cluster tests
+
+This folder contains scripts to setup an ephemeral SLURM cluster to test
+cats in a more realistic setting than the current integration tests that
+use mocking. The setup builds upon work from upstream
+https://github.com/giovtorres/slurm-docker-cluster with a patched
+Dockerfile that installs jq and uv to make CATS installation easier. Our
+patches are maintained at
+https://github.com/GreenScheduler/slurm-docker-cluster.
+
+## Pre-requisites
+
+Currently slurm-docker-cluster is only built against linux/amd64 so you
+will need to be on a 64-bit machine if you want to test this locally. You
+will also need docker installed.
+
+## Setup
+
+Clone this repository (GreenScheduler/cats) and then run
+
+```shell
+./cluster/start.sh
+```
+to fetch the `ghcr.io/greenscheduler/slurm-docker-cluster:latest` image
+and start the cluster. You can now install cats locally from the current checkout:
+```shell
+./cluster/install_cats.sh
+```
+
+Once the cluster is built and running, then you can run the following to get
+access to the control node:
+
+```shell
+docker exec -it slurmctld bash
+```
+
+## Tests
+
+An automated testing script is supplied which shows programmatic interaction
+with the slurm cluster. Currently cats schedules a short job, and the slurm
+`scontrol` output is checked to see that the job was scheduled correctly. To
+run the test:
+
+```shell
+./cluster/tests.sh
+```
diff --git a/cluster/cleanup.sh b/cluster/cleanup.sh
new file mode 100755
index 0000000..7f36631
--- /dev/null
+++ b/cluster/cleanup.sh
@@ -0,0 +1,7 @@
+#!/bin/bash
+# Cleans up resources and shuts down containers, useful for local development of slurm-docker-cluster
+set -eou pipefail
+
+pushd cluster
+docker compose down
+popd
diff --git a/cluster/docker-compose.yml b/cluster/docker-compose.yml
new file mode 100644
index 0000000..5074f17
--- /dev/null
+++ b/cluster/docker-compose.yml
@@ -0,0 +1,92 @@
+services:
+  mysql:
+    image: mariadb:10.11
+    hostname: mysql
+    container_name: mysql
+    environment:
+      MYSQL_RANDOM_ROOT_PASSWORD: "yes"
+      MYSQL_DATABASE: slurm_acct_db
+      MYSQL_USER: slurm
+      MYSQL_PASSWORD: password
+    volumes:
+      - var_lib_mysql:/var/lib/mysql
+    networks:
+      - slurm-network
+
+  slurmdbd:
+    image: ghcr.io/greenscheduler/slurm-docker-cluster:latest
+    command: ["slurmdbd"]
+    container_name: slurmdbd
+    hostname: slurmdbd
+    volumes:
+      - etc_munge:/etc/munge
+      - etc_slurm:/etc/slurm
+      - var_log_slurm:/var/log/slurm
+    expose:
+      - "6819"
+    depends_on:
+      - mysql
+    networks:
+      - slurm-network
+
+  slurmctld:
+    image: ghcr.io/greenscheduler/slurm-docker-cluster:latest
+    command: ["slurmctld"]
+    container_name: slurmctld
+    hostname: slurmctld
+    volumes:
+      - etc_munge:/etc/munge
+      - etc_slurm:/etc/slurm
+      - slurm_jobdir:/data
+      - var_log_slurm:/var/log/slurm
+    expose:
+      - "6817"
+    depends_on:
+      - "slurmdbd"
+    networks:
+      - slurm-network
+
+  c1:
+    image: ghcr.io/greenscheduler/slurm-docker-cluster:latest
+    command: ["slurmd"]
+    hostname: c1
+    container_name: c1
+    volumes:
+      - etc_munge:/etc/munge
+      - etc_slurm:/etc/slurm
+      - slurm_jobdir:/data
+      - var_log_slurm:/var/log/slurm
+    expose:
+      - "6818"
+    depends_on:
+      - "slurmctld"
+    networks:
+      - slurm-network
+
+  c2:
+    image: ghcr.io/greenscheduler/slurm-docker-cluster:latest
+    command: ["slurmd"]
+    hostname: c2
+    container_name: c2
+    volumes:
+      - etc_munge:/etc/munge
+      - etc_slurm:/etc/slurm
+      - slurm_jobdir:/data
+      - var_log_slurm:/var/log/slurm
+    expose:
+      - "6818"
+    depends_on:
+      - "slurmctld"
+    networks:
+      - slurm-network
+
+volumes:
+  etc_munge:
+  etc_slurm:
+  slurm_jobdir:
+  var_lib_mysql:
+  var_log_slurm:
+
+networks:
+  slurm-network:
+    driver: bridge
diff --git a/cluster/install_cats.sh b/cluster/install_cats.sh
new file mode 100755
index 0000000..c094ee6
--- /dev/null
+++ b/cluster/install_cats.sh
@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+# Install cats on the slurm custer
+# This relies on a cluster already setup and running, if not run
+#   ./cluster/start.sh
+set -eou pipefail
+
+docker exec slurmctld mkdir /tmp/cats
+for file in pyproject.toml ./cats; do
+  docker cp "$file" slurmctld:/tmp/cats
+done
+docker exec slurmctld uv tool install /tmp/cats
+docker exec slurmctld cp /root/.local/bin/cats /usr/local/bin/cats
diff --git a/cluster/start.sh b/cluster/start.sh
new file mode 100755
index 0000000..978ff95
--- /dev/null
+++ b/cluster/start.sh
@@ -0,0 +1,7 @@
+#!/bin/bash
+# Starts cluster
+set -eou pipefail
+pushd cluster
+docker compose pull
+docker compose up -d
+popd
diff --git a/cluster/tests.sh b/cluster/tests.sh
new file mode 100755
index 0000000..8019cef
--- /dev/null
+++ b/cluster/tests.sh
@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+# Run tests to check if slurm picks up begin time set by CATS
+# This relies on a cluster already setup and running, if not run
+#   ./cluster/start.sh
+set -eou pipefail
+
+# Step a) Run cats inside the slurmctld container and extract start time
+raw_output=$(docker exec -i slurmctld \
+  cats -d 5 --loc RG1 --scheduler=sbatch --command='ls' --format=json | \
+  awk 'BEGIN{found=0} {
+      if(!found){
+          i=index($0,"{");
+          if(i){ print substr($0,i); found=1 }
+      } else { print }
+  }')
+job_id=$(echo "$raw_output" | grep ^Submitted | awk '{print $4}')
+echo "Detected job submission ID: $job_id"
+raw_json=$(echo "$raw_output" | grep -v ^Submitted)
+raw_start=$(printf '%s\n' "$raw_json" | jq -r '.carbonIntensityOptimal.start')
+
+# Replace seconds with 00 (truncate last 6 chars and add "00")
+# Example: 2025-08-28T12:43:30.156434+00:00 -> 2025-08-28T12:43:00
+scheduled_start=$(echo "$raw_start" | sed -E 's/:[0-9]{2}\..*/:00/')
+
+echo "Expected scheduled start time: $scheduled_start"
+
+# Step b) Fetch job details
+job_output=$(docker exec -i slurmctld scontrol show job "$job_id")
+
+# Check condition 1: job is pending for BeginTime
+if (! echo "$job_output" | grep -q "JobState=PENDING Reason=BeginTime Dependency=(null)") && \
+  (! echo "$job_output" | grep -q "JobState=RUNNING Reason=None"); then
+  echo "❌ Job state/Reason is not correct, expected one of PENDING/BeginTime or RUNNING/None"
+  echo "$job_output"
+  exit 1
+fi
+
+# Check condition 2: start time matches
+if ! echo "$job_output" | grep -q "StartTime=$scheduled_start"; then
+  echo "❌ Start time does not match expected!"
+  echo "Expected: StartTime=$scheduled_start"
+  echo "Actual output:"
+  echo "$job_output"
+  exit 1
+fi
+
+echo "✅ Job is correctly delayed until $scheduled_start"