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Why we built CloudLens — and why nobody else had

There's a specific kind of anxiety that comes with being deep in the AWS Console. You're looking at an EC2 instance, or a cluster of Lambda functions, or a set of RDS databases — and you have absolutely no idea what any of it costs.

The Cost Explorer dashboard is there, of course. But it's three clicks away, requires you to leave what you're doing, run a report you probably haven't configured correctly, and stare at a chart that's accurate to 24-48 hours ago.

Meanwhile the resource you're looking at — the one you're about to scale up, or leave running over a long weekend, or forget about entirely — has no price tag.

I'd opened Cost Explorer and thought "I should check what this instance costs" approximately 200 times before I finally did something about it.

The problem is context switching

The AWS Console is where engineers make decisions. It's where you choose instance sizes, configure auto-scaling, decide whether to use on-demand or reserved capacity. Every one of those decisions has a cost implication.

But the cost information lives in an entirely separate part of the console, updated with a day's lag, presented in aggregate across services and regions that you then have to mentally map back to the resource you were just looking at.

The information gap isn't large — it's just in the wrong place. Cost Explorer has the data. The Console has the decision. They've never been in the same view.

Why nobody had built this yet

When we looked at what existed, we found two categories of tools:

The missing piece was something lightweight that lived where engineers actually work — in the Console, on the resource pages, inline.

What we built

CloudLens is a Chrome extension. When you navigate to an EC2, S3, RDS, Lambda, or DynamoDB page in the AWS Console, a small badge appears showing the month-to-date cost for that service.

Click the badge and a tooltip opens with an AI-generated plain-English summary — what's driving the cost, whether it seems normal, and one concrete action if something looks off.

That's the entire product. No new dashboard to learn. No separate app to open. No configuration beyond a read-only IAM key.

The technical constraint that shaped everything

The AWS Cost Explorer API requires SigV4-signed requests — a multi-step cryptographic signing process that normally requires the AWS SDK. The AWS JavaScript SDK is approximately 3MB. A Chrome extension that users want to install should be under 100KB.

So we implemented SigV4 signing from scratch using only the browser's native crypto.subtle API. It's about 80 lines of code and adds zero dependencies. The full extension weighs in at under 50KB.

One more thing

Your credentials never leave your browser. The AWS cost data never touches our servers. The only external call we make is directly from your browser to AWS's own API — with your own credentials, authenticated with your own IAM key.

We cannot see your AWS costs. We cannot see your account. We collect nothing. That's not a marketing claim — it's a direct consequence of the architecture.

If you work with AWS and you've ever opened a new tab to check what something costs, CloudLens is for you.