diff --git a/packages/cli/src/scaling/__tests__/scaling.service.test.ts b/packages/cli/src/scaling/__tests__/scaling.service.test.ts
new file mode 100644
index 0000000000000..d0cb038884f64
--- /dev/null
+++ b/packages/cli/src/scaling/__tests__/scaling.service.test.ts
@@ -0,0 +1,259 @@
+import { mock } from 'jest-mock-extended';
+import { ScalingService } from '../scaling.service';
+import { JOB_TYPE_NAME, QUEUE_NAME } from '../constants';
+import config from '@/config';
+import * as BullModule from 'bull';
+import type { Job, JobData, JobOptions, JobQueue } from '../types';
+import { ApplicationError } from 'n8n-workflow';
+
+const queue = mock<JobQueue>({
+	client: { ping: jest.fn() },
+});
+
+jest.mock('bull', () => ({
+	__esModule: true,
+	default: jest.fn(() => queue),
+}));
+
+describe('ScalingService', () => {
+	beforeEach(() => {
+		jest.clearAllMocks();
+		config.set('generic.instanceType', 'main');
+	});
+
+	describe('setupQueue', () => {
+		it('should set up the queue', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			const { prefix, settings } = config.get('queue.bull');
+			const Bull = jest.mocked(BullModule.default);
+
+			/**
+			 * Act
+			 */
+			await scalingService.setupQueue();
+
+			/**
+			 * Assert
+			 */
+			expect(Bull).toHaveBeenCalledWith(QUEUE_NAME, {
+				prefix,
+				settings,
+				createClient: expect.any(Function),
+			});
+			expect(queue.on).toHaveBeenCalledWith('global:progress', expect.any(Function));
+			expect(queue.on).toHaveBeenCalledWith('error', expect.any(Function));
+		});
+	});
+
+	describe('setupWorker', () => {
+		it('should set up a worker with concurrency', async () => {
+			/**
+			 * Arrange
+			 */
+			config.set('generic.instanceType', 'worker');
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			const concurrency = 5;
+
+			/**
+			 * Act
+			 */
+			scalingService.setupWorker(concurrency);
+
+			/**
+			 * Assert
+			 */
+			expect(queue.process).toHaveBeenCalledWith(JOB_TYPE_NAME, concurrency, expect.any(Function));
+		});
+
+		it('should throw if called on a non-worker instance', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+
+			/**
+			 * Act and Assert
+			 */
+			expect(() => scalingService.setupWorker(5)).toThrow();
+		});
+	});
+
+	describe('pauseQueue', () => {
+		it('should pause the queue', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+
+			/**
+			 * Act
+			 */
+			await scalingService.pauseQueue();
+
+			/**
+			 * Assert
+			 */
+			expect(queue.pause).toHaveBeenCalledWith(true, true);
+		});
+	});
+
+	describe('pingQueue', () => {
+		it('should ping the queue', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+
+			/**
+			 * Act
+			 */
+			await scalingService.pingQueue();
+
+			/**
+			 * Assert
+			 */
+			expect(queue.client.ping).toHaveBeenCalled();
+		});
+	});
+
+	describe('addJob', () => {
+		it('should add a job', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			queue.add.mockResolvedValue(mock<Job>({ id: '456' }));
+
+			/**
+			 * Act
+			 */
+			const jobData = mock<JobData>({ executionId: '123' });
+			const jobOptions = mock<JobOptions>();
+			await scalingService.addJob(jobData, jobOptions);
+
+			/**
+			 * Assert
+			 */
+			expect(queue.add).toHaveBeenCalledWith(JOB_TYPE_NAME, jobData, jobOptions);
+		});
+	});
+
+	describe('getJob', () => {
+		it('should get a job', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			const jobId = '123';
+			queue.getJob.mockResolvedValue(mock<Job>({ id: jobId }));
+
+			/**
+			 * Act
+			 */
+			const job = await scalingService.getJob(jobId);
+
+			/**
+			 * Assert
+			 */
+			expect(queue.getJob).toHaveBeenCalledWith(jobId);
+			expect(job?.id).toBe(jobId);
+		});
+	});
+
+	describe('findJobsByStatus', () => {
+		it('should find jobs by status', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			queue.getJobs.mockResolvedValue([mock<Job>({ id: '123' })]);
+
+			/**
+			 * Act
+			 */
+			const jobs = await scalingService.findJobsByStatus(['active']);
+
+			/**
+			 * Assert
+			 */
+			expect(queue.getJobs).toHaveBeenCalledWith(['active']);
+			expect(jobs).toHaveLength(1);
+			expect(jobs.at(0)?.id).toBe('123');
+		});
+	});
+
+	describe('stopJob', () => {
+		it('should stop an active job', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			const job = mock<Job>({ isActive: jest.fn().mockResolvedValue(true) });
+
+			/**
+			 * Act
+			 */
+			const result = await scalingService.stopJob(job);
+
+			/**
+			 * Assert
+			 */
+			expect(job.progress).toHaveBeenCalledWith({ kind: 'abort-job' });
+			expect(result).toBe(true);
+		});
+
+		it('should stop an inactive job', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			const job = mock<Job>({ isActive: jest.fn().mockResolvedValue(false) });
+
+			/**
+			 * Act
+			 */
+			const result = await scalingService.stopJob(job);
+
+			/**
+			 * Assert
+			 */
+			expect(job.remove).toHaveBeenCalled();
+			expect(result).toBe(true);
+		});
+
+		it('should report failure to stop a job', async () => {
+			/**
+			 * Arrange
+			 */
+			const scalingService = new ScalingService(mock(), mock(), mock());
+			await scalingService.setupQueue();
+			const job = mock<Job>({
+				isActive: jest.fn().mockImplementation(() => {
+					throw new ApplicationError('Something went wrong');
+				}),
+			});
+
+			/**
+			 * Act
+			 */
+			const result = await scalingService.stopJob(job);
+
+			/**
+			 * Assert
+			 */
+			expect(result).toBe(false);
+		});
+	});
+});
diff --git a/packages/cli/src/scaling/job-processor.ts b/packages/cli/src/scaling/job-processor.ts
index 6057a1937db76..693c9e3a74fb7 100644
--- a/packages/cli/src/scaling/job-processor.ts
+++ b/packages/cli/src/scaling/job-processor.ts
@@ -16,7 +16,7 @@ import type PCancelable from 'p-cancelable';
  */
 @Service()
 export class JobProcessor {
-	private readonly runningJobs: { [jobId: JobId]: RunningJob } = {};
+	private readonly runningJobs: Record<JobId, RunningJob> = {};
 
 	constructor(
 		private readonly logger: Logger,
diff --git a/packages/cli/src/scaling/scaling.service.ts b/packages/cli/src/scaling/scaling.service.ts
index c52a82e8a0da6..21d05fceff850 100644
--- a/packages/cli/src/scaling/scaling.service.ts
+++ b/packages/cli/src/scaling/scaling.service.ts
@@ -94,12 +94,12 @@ export class ScalingService {
 
 		try {
 			if (await job.isActive()) {
-				await job.progress({ kind: 'abort-job' });
+				await job.progress({ kind: 'abort-job' }); // being processed by worker
 				this.logger.debug('[ScalingService] Stopped active job', props);
 				return true;
 			}
 
-			await job.remove();
+			await job.remove(); // not yet picked up, or waiting for next pickup (stalled)
 			this.logger.debug('[ScalingService] Stopped inactive job', props);
 			return true;
 		} catch (error: unknown) {