# Order Dispatch Systems at Scale

DevFeed: [Order Dispatch Systems at Scale](<https://devfeed.tech/articles/order-dispatch-systems-at-scale-30799.md>)

Original publisher: [Read original article](<https://devblog.kogan.com/blog/order-dispatch-systems-at-scale>)

Author: Guest User

Published: 2025-07-28T01:53:56Z

Content type: tutorial

Language: en

Sources: [Kogan.com](<https://devfeed.tech/sources/kogan-com.md>)

Topics: [Amazon Simple Queue Service (SQS)](<https://devfeed.tech/topics/amazon-simple-queue-service-sqs.md>), [event driven](<https://devfeed.tech/topics/event-driven.md>), [Scalability](<https://devfeed.tech/topics/scalability.md>), [Amazon Web Services](<https://devfeed.tech/topics/aws.md>), [Microservices](<https://devfeed.tech/topics/microservices.md>), [microservices architecture](<https://devfeed.tech/topics/microservices-architecture.md>), [Latency](<https://devfeed.tech/topics/latency.md>)

Tags: [aws](<https://devfeed.tech/tags/aws.md>), [concurrency](<https://devfeed.tech/tags/concurrency.md>), [event](<https://devfeed.tech/tags/event.md>), [event-driven](<https://devfeed.tech/tags/event-driven.md>), [latency](<https://devfeed.tech/tags/latency.md>), [microservices-architecture](<https://devfeed.tech/tags/microservices-architecture.md>), [scale](<https://devfeed.tech/tags/scale.md>), [sqs](<https://devfeed.tech/tags/sqs.md>)

## AI overview

This tutorial compares vertical and horizontal scaling, pull-based queues using AWS Simple Queue Service, and event-driven architecture for order dispatch systems. It describes queue trade-offs and explains how event subscribers can process orders independently and scale separately.

## Source excerpt

How to load-balance like a seasoned waiter Software systems often parallel the real world. Imagine running a busy restaurant, where customers line up to make orders whilst the kitchen prepares the meals. In the software world, your users are the customers, and your backend services are the kitchen. With more people online than ever before, that line might start to grow out the front door. The ability to scale is no longer optional, it is essential. Know Your Options Vertical Scaling - Scale Up Horizontal Scaling - Scale Out Expanding your restaurant by adding more tables or a larger kitchen. In software terms, this means scaling up your infrastructure. More powerful CPUs, larger memory, increased throughput etc. This is a relative quick fix, but comes with diminishing returns and limits on how big everything can get. Opening new restaurant locations to serve more customers simultaneously and distribute existing flows. In software terms, this means adding more API servers, more worker nodes or creating many database replicas. This approach is more flexible and scalable than vertical scaling in the long term. A Steppingstone - Queues Just like how customers queue for their order, we create a pull-based task queue for our order management system using AWS Simple Queue Service (SQS). Tasks get queued into the SQS, and a consumer service will continuously poll this queue to process the tasks. This gives a lot of control for the queue consumer to dictate the frequency of polling, which works well in systems that cannot handle high throughput or requires non-concurrency like the SAP ERP (more on that later). SQS also provides built-in dead-letter-queues, retry policies, at least once delivery guarantee and scales automatically. Vertical scaling involves sizing up the compute power of the consumer (CPU, RAM etc). Horizontal scaling involves spinning up more consumers of the SQS. However, queues have limitations: Latency between order arrival and processing. Inefficient poll