What are Lambda Layers?

Lambda layers provide a mechanism to externally package dependencies that can be shared across multiple functions.

using layers reduce the lines of code and size of the application artefacts and simplifies dependency management.

lambda layers can come from multiple sources - you can create your own layers, you can implement an AWS managed layer with a third party dependency, or you can grab a third party layer from a trusted developer.

you can have up to 5 layers per function and this is how it looks when you have a layer configured in your function.

you can see it in your function overview.

When you click on it it takes you to the layer definition, where you can edit the layer or add a new one.

if you want to learn more about layers check my video on layers, so you can learn how to do layers with iac.