Ship a paid Chrome extension this month.
The exact stack behind Job Red Flag Detector and ToS Scanner — template repo, working backend, written-down lessons. Lifetime access to the GitHub repo.
You're in. Watch your inbox.
Built on Cloudflare Workers + Stripe + Anthropic API. MV3.
Built from the same code that runs two live Zurhaar Tools products.
Job Red Flag Detector
Live on Chrome + Edge
Approved May 11
ToS Scanner
In Chrome + Edge review
Submitted May 18
What's inside
Code that ships to production
- ✓ Working sample Chrome extension (MV3 manifest with side panel + popup + content scripts wired up)
- ✓ Cloudflare Worker backend — Stripe webhooks, license keys, credit metering, refund + chargeback handlers
- ✓ Astro storefront — pricing page with tabs, success page that fetches the license key, recover flow
- ✓ D1 schema + migrations — licenses, credit transactions, status state machine (active / suspended / revoked / deleted)
- ✓ Resend email templates — purchase confirmation + license recovery
- ✓ Playwright tests in 3 layers — shared state machine, content extraction with fixtures, real-API smoke
Lessons from shipping two real extensions
- ✓ EU-compliant privacy + terms templates (most kits skip this — get rejected from Chrome Web Store for it)
- ✓ The Promise.race gotcha — chrome.scripting.executeScript hangs forever when permissions are revoked
- ✓ The activeTab-vs-host-permissions matrix — the #1 reason extensions get rejected
- ✓ The 7-state side panel pattern — welcome, initial, loading, results, no-credits, error, no-content
- ✓ The 4-strategy content extractor that works on any site (selectors → markers → keyword scoring → fallback)
- ✓ Shadow-DOM extraction (for LinkedIn-style sites) and MutationObserver for SPAs
What it doesn't include
- ✕ The actual prompts behind Job Red Flag Detector and ToS Scanner (those are the products — kit ships a neutral example prompt that demonstrates the same JSON-output convention)
- ✕ A hosted Worker — you run your own Cloudflare account, that's the point
- ✕ Auto-deploying CI/CD (optional chapter in the docs — left out so the kit works without it)
Pricing
One-time payment. Lifetime access to the repo and every update.
Starter
For solo developers building their first extension
- ✓ Full code (extension, backend, website)
- ✓ EU-compliant privacy + terms templates
- ✓ Sample extension + second-extension scaffold
- ✓ Playwright tests (3 layers)
- ✓ All technical docs
- ✓ Lifetime access to the repo
- ✓ Lifetime updates
- ✓ License: 1 developer
- ✓ 30 days email support
Pro
For shipping a real product to market
- ✓ Everything in Starter
- ✓ License: up to 5 developers
- ✓ 6 months email support
- ✓ First-paying-customer playbook
- ✓ Featured Build slot on the developers page (if you opt in)
Studio
For agencies and studios building multiple extensions
- ✓ Everything in Pro
- ✓ License: unlimited developers
- ✓ Lifetime email support
- ✓ 1 hour async code review within 30 days of purchase
How it works
Buy on Gumroad
Choose a tier and pay once. Gumroad handles checkout, EU VAT, the lot.
Enter your GitHub username at checkout
One required custom field — your GitHub handle, that's it.
Get a repo invite in your email
Within seconds. Pull access, lifetime.
Ship your extension
Read the quickstart, deploy the worker, build your first extension.
The full mechanics: Gumroad sends a webhook to our backend → backend invites your GitHub user as a collaborator → you accept the invite and clone. If you typo your username, you can fix it from a self-service redemption page.
Questions
How long does it take to ship a real extension with this?
If you've never built a Chrome extension before, expect a weekend to get the sample running on your own Cloudflare account, then 2–4 weeks to design, build, test, and submit your own extension. The kit removes the "what do I even need to set up" question — you're left with just the extension-specific work.
Do I keep updates after I buy?
Yes. Lifetime access to the repo means you can pull every kit update Andreas ships, forever. No subscription, no renewal.
What if I don't have a GitHub account?
You'll need one — it's free. The kit lives in a private GitHub repo, and you get access by being invited as a collaborator. If you enter the wrong username at checkout, there's a recovery page that lets you fix it.
What's the refund policy?
14 days, no questions asked. After that, it's non-refundable — same as buying a book. If you refund, you're removed from the repo automatically.
What tech do I need to know?
JavaScript (you'll be writing some). Familiarity with HTML/CSS for the side panel and the website. The setup docs assume you can use a terminal, a text editor, and follow a step-by-step guide. You do not need to know Cloudflare, Stripe, or Manifest V3 in advance — the docs cover all three from scratch.
Does the kit include hosting costs?
No, but they're effectively zero for a starting business. Cloudflare Workers and D1 are free up to 100k requests / 5M reads a day. Resend is free for the first 100 emails a day. Stripe charges per transaction (1.5% + €0.25 in the EU), not monthly. The only fixed cost is your domain (~€10/year).
Can I sell the extensions I build with this?
Yes. The kit license allows commercial use on every tier — what you build with the kit is yours to sell. The only thing the license forbids is redistributing the kit code itself.
Is the kit a subscription?
No. One-time payment, lifetime repo access, lifetime updates. If you pay for something, you have it forever.
What's in the Studio tier's code review?
A 1-hour async code review within 30 days of purchase. Send Andreas your repo, get back written feedback on architecture, gotchas you've hit, and what to clean up before you submit to the Chrome Web Store.
What's the sample extension that comes with the kit?
It's called Pageword Counter Pro — a purpose-built teaching example that counts words on a page and shows reading time. It uses the same content extractor, same backend, same state machine, same tests as Job Red Flag Detector and ToS Scanner. It's a working extension you can actually load into Chrome and run, not a stub.
Are the prompts from Job Red Flag Detector and ToS Scanner included?
No — those are the products. The kit ships a neutral example prompt that demonstrates the same JSON-output convention without copying the competitive vocab. You write your own prompts for your own products.
Where does checkout happen?
On Gumroad. After purchase, you'll get a confirmation email from Gumroad and a separate email from us with the GitHub invite link.
When can I buy?
Joining the waitlist is the only way to know. We'll email you the day it opens. No spam, no marketing list — one email per launch.
Be first when it launches
Drop your email below. We'll send one message the day the kit goes live. That's the whole list.
Other Zurhaar Tools
Built by the same person. One support email, one quality bar.
Job Red Flag Detector
Spots warning signs in job postings — vague salary, unrealistic requirements, toxic culture signals.
Learn more →ToS Scanner
Scans Terms of Service and Privacy Policies, highlights dangers in plain language.
Learn more →