Tips for AI-Assisted Coding (Sep 19, 2025)

In the past few weeks, I’ve become a power user of agentic AI coding tools. Thousands of lines of code have been written, dozens of bugs have been solved, and entire repositories have been refactored. At least 95% of the code was written by the AI. I just made small tweaks here and there, mostly cosmetic changes to styling and text labels. Over these weeks, I’ve learned a lot. This post is a list of tips for people new to AI coding agents.
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Fixing 302 Redirects on Static S3-websites

I love static websites deployed on S3. They are maintenance free and dirt cheap to run. One issue I've had with them is that S3, in certain cases, uses 302 redirects when 301 would be a more appropriate choice. In this article we fix that.
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How to Back Up Your Files Using S3 and Glacier

AWS S3 and Glacier make cloud backups easy and ridiculously cheap. Let's learn how to make incremental backups using AWS CLI and versioned buckets.
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Building a Real-Time Image Optimizer Using Lambda@Edge and Amazon CloudFront

A real-time image optimizer is a service that resizes the requested image according to specific query parameters. It then caches the image so that if the same image with the same parameters is requested again, it will be served from the cache. In this tutorial, I show you how to build one from scratch.
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Guide to Monitoring and Controlling AWS Lambda Costs

Lambda functions scale almost infinitely, but your budget most likely won't. This guide teaches you some tools for monitoring and controlling the costs of your serverless solutions.
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Using Multi-Factor Authentication with AWS CLI

Having multi-factor authentication in the web UI is great but I do most of my AWS work via the CLI, so just blocking access to the GUI is not sufficient. In this tutorial, I explain how to apply multi-factor authentication also to your CLI/API users.
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Why the Web Is a Mess and How We Can Fix It

There is a lot of talk about web standards and how to extend them, but little about the fundamental challenge the web should overcome: executing arbitrary code from arbitrary corners of the Internet - securely.
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Build Your Own React - Part 1: Simple Elements

Learn how React works by implementing it yourself. In this series, we build a very simple React-like framework from scratch. I call it the Minimum Viable React. Although the implementation is not exactly the same as that of React, it still gives you a very good idea of how React and other frameworks like it work under the hood.
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Build Your Own React - Part 2: Components

In this article, we pick up where we left off in part 1. This time, we add components to our framework.
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Build Your Own React - Part 3: State and Lifecycle

In part 2 we added components to Minimum Viable React. In this 3rd part we'll add state and lifecycle methods.
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Build Your Own React - Part 4: Lists and Keys

In this 4th and final part we improve list reconciliation by adding keys.
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Encapsulation in JavaScript

Encapsulation is a powerful technique that helps you avoid bugs and modularize your programs for easier development. It is especially important when you're working with other developers or if you are authoring an open source library for others to use.
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How JavaScript Promises Work Under The Hood

Promises are a useful abstraction for JavaScript programmers, but have you ever wondered how they work under the hood? I made a detailed video on implementing promises.
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