A year ago, I built my first Chrome extension. It took the better part of a week.
A few days ago, I built my second Chrome extension. It took four hours.
Same developer. Similar complexity. Almost no retained knowledge about Chrome extension development between the two projects. The difference was the AI.
The First Extension
The first project was a scraper for Amazon Seller Central—pulling data out of the seller dashboard and generating reports. I built it with one of the ChatGPT 4.x models, whichever was current at the time.
It was painful. But impressive at the time.
Not because Chrome extensions are impossibly hard, but because I’d never built one before and the AI couldn’t quite get me there cleanly. Every step involved back-and-forth. I’d describe what I wanted, get code that didn’t work, debug it, explain the error, get a fix that broke something else, repeat.
The manifest file alone took multiple attempts to get right. Permissions, content scripts, background workers—each concept required me to learn enough to understand why the AI’s suggestions weren’t working, then nudge it toward a solution.
By the end of the week I had a working extension, but I’d earned it through iteration and frustration.
The Second Extension
Fast forward to last week. I needed another Chrome extension—this one scrapes recipe information from web pages and submits it to a backend API. Different purpose, but similar complexity to the first project.
I opened Claude Code and described what I wanted.
One prompt later, I had a working prototype running locally.
Not a starting point. Not scaffolding that needed extensive modification. A working extension that did the core job. From there, it was small iterations—mostly around authentication with my backend. But the foundation was solid from the first response.
What Changed
The moments that stood out weren’t dramatic. They were just… easy in a way that felt wrong.
The manifest: Chrome extensions require a manifest.json file that defines permissions, scripts, icons, and metadata. Last year, this was a source of misunderstandings and rejections. This time, Claude one-shot it. Correct permissions, proper structure, sensible defaults. I didn’t have to understand why it worked—it just did.
The submission process: I’d completely forgotten how to submit an extension to the Chrome Web Store. Claude walked me through it—descriptions, screenshots, privacy policy requirements, the review process. Not generic advice, but specific guidance tailored to what I’d built.
Performance and security: After the core functionality worked, I prompted my way through improvements. “Make this more efficient.” “Are there any security concerns?” Each time, I got specific changes to the code. I did a cursory review to make sure nothing looked insane, but I didn’t have to dive deep into the implementation to fix anything myself.
Four hours from start to ready-for-submission.
The Gap Is Closing
I’m not a better developer than I was a year ago—at least not at Chrome extensions. I’d forgotten almost everything I learned during that first project. But the AI got dramatically better.
ChatGPT 4.x was helpful but unreliable. It got me part of the way there, then I had to fight through the gaps. Claude Code with Opus 4.5 understood what I was trying to build and just… built it.
The difference isn’t subtle. It’s not 20% faster or “somewhat easier.” It’s the difference between a week of grinding and an afternoon of iterating.
What This Means
I think about this when people ask whether AI is actually useful for development, or if it’s just hype. The answer depends entirely on when you last tried it.
If your experience with AI coding assistants was ChatGPT circa 2024, you probably remember the frustration—code that almost worked, endless debugging, the feeling that you could’ve done it faster yourself. That was real.
But the tools from six months ago aren’t the tools from today. The gap between “AI assistant that helps” and “AI that builds” is closing fast. For a task I’d done exactly once before, with knowledge I’d completely lost, I went from a week to four hours.
That’s not incremental improvement. That’s a phase change.
Both extensions are in production. One took a week of frustration. One took an afternoon.