Automating AWS Lambda Deployments with AWS CodePipeline

Introduction

Automation is the backbone of modern software delivery in today’s fast-paced cloud environment. Continuous Integration and Continuous Deployment (CI/CD) pipelines ensure applications are delivered faster, with fewer errors, and minimal downtime.

When it comes to serverless applications, AWS Lambda allows developers to run code without provisioning or managing servers. But how do you continuously update your AWS Lambda functions with new code changes seamlessly?

This is where AWS CodePipeline comes in. It’s a fully managed CI/CD service that automates the build, test, and deployment phases.

In this blog, we will walk through how AWS CodePipeline can deploy changes automatically to an AWS Lambda function, ensuring fast, reliable, and repeatable delivery.

Why Use AWS CodePipeline with AWS Lambda?

• End-to-end automation: From code commit to deployment.
• Serverless focus: No servers to manage during the deployment.
• Integration with AWS services: Works seamlessly with AWS CodeCommit, AWS CodeBuild, Amazon S3, Amazon CloudWatch, and AWS IAM.
• Faster innovation: Reduce manual steps and push new features quickly.

AWS CodePipeline with AWS Lambda

AWS CodePipeline is a CI/CD orchestration service that allows you to model your release process as a series of stages. With AWS Lambda as the target, AWS CodePipeline automates packaging, testing, and deploying your serverless code.

A typical AWS Lambda pipeline involves:

1. Source Stage – Tracks code changes from repositories like AWS CodeCommit, GitHub, or Amazon S3.
2. Build Stage – This stage uses AWS CodeBuild to package dependencies and prepare deployment artifacts.
3. Deploy Stage – Automatically updates the AWS Lambda function with the new build.

This integration provides a serverless-first approach to CI/CD where you don’t need to manage servers at any stage of the delivery lifecycle.

Architecture Overview

Here’s a simple flow of how the pipeline works:

1. Source Stage: Code is pushed to a repository (AWS CodeCommit, GitHub, GitLab, or Amazon S3).
2. Build Stage: AWS CodeBuild packages the AWS Lambda code and dependencies into a deployment package (ZIP).
3. Deploy Stage: AWS CodeDeploy (with AWS CodePipeline) updates the AWS Lambda function with the new package.

Architecture Diagram:

Step-by-Step Guide

1. Prerequisites

• An existing AWS Lambda function with an alias was created. (This is referred to at the deploy stage of the AWS CodePipeline).
• AWS CLI or Management Console access.
• An Amazon S3 bucket for storing artifacts.
• AWS IAM roles for AWS CodePipeline, AWS CodeBuild, and AWS Lambda.

2. Create the Source Stage

• If using AWS CodeCommit:
  • Push your AWS Lambda source code into an AWS CodeCommit repo.
• If using Amazon S3/GitHub:
  • Configure as the pipeline source. Let’s have the code in GitHub and connect this repository to the AWS CodePipeline as a source.

3. Build Stage with AWS CodeBuild

• Create a buildspec.yml file:

• This ensures dependencies are moved as expected with the files and folder structure. It needs to be packaged as a zip, and deploy the below buildspec.yaml

4. Deploy Stage with AWS CodePipeline

• Use AWS CodeDeploy for AWS Lambda or directly configure AWS CodePipeline Deploy Action.

Your code pipeline will look as follows, with three stages added:

• Define the AWS Lambda function name in the deployment stage.

• Each successful build automatically updates the function.

Best Practices

• Use separate stages (dev, stage, prod) with manual approvals before production.
• Store sensitive credentials in AWS Secrets Manager.
• Enable Amazon CloudWatch Alarms to roll back failed deployments.
• Version your AWS Lambda functions for rollback safety.

Conclusion

Integrating AWS CodePipeline with AWS Lambda allows you to achieve a fully automated CI/CD workflow tailored for serverless applications. This accelerates feature delivery and ensures consistency, reliability, and minimal downtime.

Drop a query if you have any questions regarding AWS CodePipeline or AWS Lambda and we will get back to you quickly.

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