Building serverless applications on AWS
I've been building serverless applications on AWS for over ten years. I was immediately hooked when AWS Lambda was launched in 2014 and have been using it as the main way to build web services using JavaScript, and later TypeScript ever since.
For developers who come from classic, instance-based architectures, working with serverless is a huge paradigm shift. It's not natural, nor obvious. In this blog post I am sharing the current set of material I give to colleagues who want to learn the idiomatic way of building serverless.
The basics
There are some fundamentals when building scalable web services, which apply both in instance-based and serverless architectures.
REST in practice is a must read.
The Twelve-Factor App provides important design aspects for web services in general, but this applies very well to serverless applications.
In my talk Serverless Architecture for IoT on AWS I explains the benefits of serverless in general in why it is especially suitable for IoT applications. I provide an introduction to serverless in general, and how it is implemented at the different cloud vendors (looking at AWS and Azure, where I have implemented the same application using the respective cloud's idiomatic way), and why it is especially relevant for IoT deployments.
Learning AWS serverless
Of course, always check the official AWS resources on AWS Lambda:
For training my colleagues I have used the AWS Dev Hour: Building Modern Applications training, with the added challenge of writing tests for it. My colleague Lena Kråkevik Haraldseid has a talk about her learnings from this exercise: Testing serverless applications.
The recently released book Serverless Development on AWS offers a great way to learn more about the potential of the serverless paradigm and the mindset shift needed to tap its full potential. It’s a must read for every developer that works with AWS because more and more powerful services on AWS are built from the ground up as serverless offering.
Testing
One of the challenges when building serverless applications is testing. You are building on the shoulder of giants, and are using services that no longer run on your (CI) machine. In my talk It does not run on my machine: Integration testing a cloud-native application I take you through the challenge of testing a cloud-native application. I cover the challenges when developing solutions on top of serverless components which you cannot run on your own machine and how I designed a BDD driven approach to run the integration tests.
Here is AWS' best practice on testing Lambda: How to test serverless functions and applications.
Reference projects I have built
It's always best to look at actual code, so these are the open-source projects that are available which I have worked on: