Fraud detection for e-commerce and marketplaces — SignupDoggy

How e-commerce platforms and marketplaces use SignupDoggy to filter account creation fraud, prevent promo abuse, and stop fake reviews. Plus how to combine with payment-fraud detection like Stripe Radar.

Fraud detection for e-commerce and marketplaces — SignupDoggy

E-commerce platforms and marketplaces have a specific problem at signup:

- Fake account creation for promo abuse (new account, get the 10% off code, repeat)
- Fake reviews from accounts that never bought anything
- Buyer-seller fraud where the buyer's account is throwaway
- Account takeover for stored credit cards

SignupDoggy is the signup-time gate. It is NOT a payment-fraud solution.

WHAT IT CATCHES AT SIGNUP

- Disposable email addresses (200,000+ domains)
- VPN / Tor / proxy users
- Role-based email addresses (admin@, support@, info@)
- Bot-driven signup scripts
- Multi-account abuse patterns

WHAT IT DOES NOT CATCH

- Payment fraud at checkout (use Stripe Radar or Signifyd for this)
- Chargebacks after the fact (use a chargeback management service)
- Account takeover (use Auth0 or Clerk for this)
- Promo-code abuse after the fact (use a promo-abuse detection service)

THE COMBINED STACK

The right e-commerce fraud stack in 2026:

1. SignupDoggy ($0.01/call) — at signup, filter bot account creation
2. Stripe Radar ($0.05/call or included free with Stripe) — at checkout, score the transaction
3. Signifyd or Kount (enterprise) — for chargeback management

The signup-time gate keeps your user database clean. The checkout-time gate keeps your chargeback rate low. They are different problems, different tools, different points in the funnel.

THE INTEGRATION

```js
// At signup, before creating the user
const result = await fetch('https://signupdoggy-api.jeffrinjames99.workers.dev/v1/check', {
  method: 'POST',
  headers: { 'X-API-KEY': process.env.SIGNUPDOGGY_KEY, 'Content-Type': 'application/json' },
  body: JSON.stringify({ email, ip }),
}).then(r => r.json());

if (result.recommendation === 'block') {
  return res.status(400).json({ error: 'Invalid email' });
}
```

10 lines of code. Add to your signup handler. Ship in an afternoon.

THE NUMBERS

For an e-commerce platform with 100,000 signups/month:
- Without filtering: ~30,000 bot accounts per month in your database
- Each bot account eventually tries promo abuse, fake reviews, or chargeback fraud
- Average cost per bot account: $5-$50 in lost margin and ops time
- Total: $150,000-$1,500,000/year in bot-related losses
- With SignupDoggy: $1,000/month (100,000 signups × $0.01)
- ROI: 12x-150x

The signup-time gate is the cheapest insurance you can buy for an e-commerce platform.