Blog
Thoughts on engineering, design, and building great products.
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.
CodeBuild Advanced: Environment Variables, Secrets, and Cache
Real builds need config and secrets: an API URL, a key, a database password. This article passes them into CodeBuild the right way — plain variables declared inline, sensitive values pulled from SSM Parameter Store and Secrets Manager and masked automatically by CodeBuild in the logs. Plus enabling cache for faster builds. All tested for real, with logs.
CodeBuild: Project, buildspec.yml, and the First Build
Build the build stage: create a CodeBuild project wired to the CodeCommit repo, write buildspec.yml defining the build phases, run a real build, then read the CloudWatch log to see how each phase runs. Dissect the mechanism — CodeBuild stands up a temporary container, runs buildspec in phase order, pushes the artifact to S3 and logs to CloudWatch.
CodeCommit: The Source of Code for the Pipeline
Build the source stage: create a CodeCommit repo, connect Git with git-remote-codecommit (uses AWS credentials, no separate Git password to store), push a sample app, then walk through the branch and pull request flow with the AWS CLI. This is where the code lives and the starting point for every pipeline run in later articles.