Lambda Layers

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by The Captain

August 3, 2023

AWS Lambda Layers Tutorial: Simplify Code Reuse and Management

Lambda Layers is a powerful feature offered by AWS Lambda that simplifies code reuse and management in serverless applications. With Lambda Layers, you can manage and share common pieces of code across multiple Lambda functions, making it easier to maintain, update, and control dependencies. In this tutorial, we will explore the benefits of Lambda Layers and guide you through the process of creating and using them in your AWS Lambda functions.

Why Use Lambda Layers?

As your serverless applications grow, you might find yourself duplicating boilerplate code or having to manage common libraries across multiple Lambda functions. This can lead to redundant code, increased deployment times, and difficulties in managing dependencies. Lambda Layers solves these challenges by providing a central repository for common code and libraries, which can be shared across functions without the need for duplication.

Creating a Lambda Layer

To create a Lambda Layer, you need to package your code and dependencies into a .zip file. Start by organizing your code and dependencies in a directory structure. Then, using the AWS Command Line Interface (CLI) or AWS Management Console, create a .zip file that includes your code and any required dependencies.

Once you have your .zip file ready, navigate to the AWS Lambda service in the AWS Management Console and choose "Layers" from the sidebar. Click on the "Create Layer" button and provide a name, description, and upload the .zip file. You can also specify compatible runtimes and manage permissions for the layer.

Using Lambda Layers in Lambda Functions

After creating a Lambda Layer, you can easily include it in your Lambda functions. When configuring your function, navigate to the "Layers" section and click on the "Add a layer" button. Select the desired layer from the list and save the changes. The layer will be associated with your function, and the shared code will be accessible during execution.

When a Lambda function is invoked, AWS automatically attaches the associated layers in the order specified. This enables the function to access the shared code and libraries provided by the layers. You can specify multiple layers in a function, and they will be merged in the order of attachment.

Managing and Versioning Layers

AWS provides convenient management and versioning options for Lambda Layers. Using the AWS Management Console or CLI, you can easily publish new versions of a layer whenever you make updates. Each version of a layer allows you to manage permissions, maintain compatibility with different runtime versions, and provide a description of changes.

Additionally, you can control which versions of a layer your Lambda functions use. By specifying a specific version or using the latest version, you can ensure your functions consistently use tested and validated code.


AWS Lambda Layers simplifies code reuse and management in serverless applications by allowing you to share common code and libraries across multiple Lambda functions. By creating and attaching layers to your functions, you can reduce redundancy, improve maintainability, and streamline the management of dependencies. Whether you want to share custom code, third-party libraries, or system-level dependencies, Lambda Layers provides an efficient way to scale and manage your serverless applications.