Blog
Thoughts on engineering, design, and building great products.
CodePipeline: Wiring Source, Build, Deploy Into a Chain
Until now every stage ran by hand. CodePipeline wires them into one automated chain: Source pulls code from CodeCommit, Build calls CodeBuild, Deploy calls CodeDeploy — artifacts flow from one stage to the next. This article builds the first pipeline, runs it for real, and dissects how artifacts pass between stages.
Blue/Green Deploy With ALB and Automatic Rollback
In-place deploys have a window where a machine is offline. Blue/green avoids it: stand up a new fleet (green) in parallel, validate it, then shift traffic over with a load balancer — blue stays intact for an instant return. This article builds an ALB, switches the deployment group to blue/green, runs it for real (including a very realistic IAM error), and configures automatic rollback per CloudWatch alarm.
Deploying to an Auto Scaling Group and Deployment Config
From one instance to many: deploying to an Auto Scaling Group. Create a launch template and ASG, attach the deployment group to the ASG, then pick a deployment config (OneAtATime, HalfAtATime, AllAtOnce) to control whether the deploy goes machine by machine or all at once. Plus a key mechanism: CodeDeploy automatically deploys the latest revision to instances the ASG launches later.
CodeDeploy Lifecycle Hooks: Order, Variables, and When a Hook Fails
A deep dive into CodeDeploy's hook layer: what order the lifecycle events run in, which hook fits which job, why ApplicationStop runs from the old revision rather than the new one, the environment variables CodeDeploy passes into your scripts, and what happens when a hook fails — the deploy stops right there, and later events don't run.
CodeDeploy: The First In-Place Deploy to EC2
Opening Part IV: putting artifacts onto EC2 with CodeDeploy. Stand up an instance with the agent, create an application and a deployment group targeted by tag, write appspec.yml with lifecycle hooks, then run the first in-place deploy — watch the agent pull the revision from S3 and run through each lifecycle event until the app actually serves.
CodeArtifact: An Internal Package Repository for Builds
Real builds depend on a stream of packages from the Internet — risky when an external source changes or disappears. CodeArtifact is a managed package repository: both a proxy cache for public PyPI/npm and a store for your private packages. This article creates a domain and repository, publishes a Python package then reinstalls it from CodeArtifact, and wires it into CodeBuild.
CodeBuild Test Reports: A Build Must Not Only Run, It Must Be Correct
A successful build does not mean the code is correct — it only means the commands ran without error. This article has CodeBuild run real tests (pytest) and collect the results into a viewable test report: total count, pass/fail, each case. And why you should let a failing test fail the build, blocking broken code before it reaches deploy.