Cognito can tell you who a user is, but it cannot answer what they are allowed to do. An authorizer Lambda gives you one place to evaluate permissions before a request reaches your backend, with Cognito for identity and a separate permission source for authorization.
Automatically optimize images the moment they're uploaded to S3 using Lambda functions triggered by S3 events. Perfect for user-generated content and dynamic workflows.
SQS is AWS's managed message queue service. Messages go in, consumers pull them out, and the queue handles everything in between. Here's what it is, when to use it, and how to implement the common patterns.
The model is just token prediction. An agent harness is everything else - the loop, the tools, the memory, and the safety controls that make a model actually useful.
Pi is a minimal, extensible coding agent. This article walks through building a permission gate extension that intercepts dangerous bash commands before they run.
When your database goes down, every service that depends on it starts throwing errors. Composite alarms let you express alarm logic so you get one page per root cause, not one per symptom.
When one Lambda isn't enough, Step Functions lets you orchestrate multi-step workflows with retries, error handling, and a full execution history built in.
The Events API is built and fast. Now POST /events and DELETE /events/{id} need auth. Lambda authorizers let you validate any token format from any issuer before a request ever reaches your handler.
The architecture decisions that make a Lambda-backed API fast - per-route function layout, lean handlers, per-function dependencies, ARM64, and CDK patterns that compound into short cold starts.
What happens during a Lambda cold start, how to measure it with X-Ray and CloudWatch Logs Insights, and how to reduce it with lean packages, init code patterns, and provisioned concurrency.
How to add end-to-end tests to a React app with Playwright, including checkout flow testing for e-commerce, and run them automatically on every pull request.
Hardcoded config doesn't scale and hardcoded secrets are a security incident waiting to happen. Here's how to manage environment variables, secrets, and configuration for Lambda functions on AWS - from local development to production.
RDS in a private subnet doesn't need a bastion host or an open port 22. AWS Systems Manager port forwarding creates an encrypted tunnel from your laptop to a private endpoint - no public IP, no SSH key management required. Here's how to set it up with CDK.
EC2 is AWS's virtual machine service - rent compute capacity in the cloud, pay by the hour. Here's what it is, when to use it over serverless options, the configuration knobs that matter, and how to provision it with CDK.
The Intersection Observer API lets you detect when elements enter or leave the viewport - without scroll event listeners. Here's what it solves, how it works, and real patterns you can use today.
SNS is AWS's pub/sub messaging service. One message in, many subscribers notified. Here's what it is, when to use it, and how to implement the common patterns.
GitHub Actions is CI/CD built directly into GitHub. No external service to configure. Push code, merge a PR, cut a release - automation runs. Here's what it is, how workflows are structured, and real examples for the most common use cases.
You have an Aurora database running in AWS. Now you need to get your schema into it. Here's how to define your data models with SQLAlchemy, manage migrations with Alembic, and run them against Aurora - step by step.
S3 is AWS's object storage service - store any file at any scale. Here's what it is, what it's built for, what it isn't, what it works with, and how to deploy it with CDK.
Definitions for the AWS services and concepts covered across the architecture articles on this site. VPCs, subnets, Lambda, API Gateway, EventBridge, SQS, Step Functions, RDS, Aurora, security groups, and everything in between.
Lambda is AWS's serverless compute service - run code without managing servers, pay only for what you use. Here's what it is, why it's worth knowing, when to reach for something else, and how to deploy it with CDK.
The classic three-tier architecture - presentation, application, and data layers inside a VPC - is the foundation of most production AWS deployments. Here's how it works, how subnets and security groups enforce it, and how to deploy it with CDK.
EventBridge is a serverless event bus that connects your applications with data from AWS services, SaaS apps, and custom sources. Learn what it is, the problems it solves, and how to implement it with CDK.
Build interactive data visualizations using D3.js and React. See live examples of bar charts, donut charts, and line charts you can embed directly in your content.