PayWebhookLab

Who it's for

indie devs and small engineering teams who currently debug webhooks using RequestBin/ngrok + manual curl scripts

The problem

time + money: debugging production payment webhook bugs costs hours to days, causes missed refunds/failed order fulfillments and chargebacks; teams currently cobble together manual repros and rely on flaky staging tunnels

How to build it

web UI + single-line CLI installer that gives a per-endpoint test run; integrations: one-click GitHub Actions step, SaaS dashboard showing test history, webhook endpoints stored per-project

How it makes money

projects (teams or agencies) pay $15-50/month (tiered by endpoints/tests) because payment bugs cost far more than that; they can't use free RequestBin variants because those don't produce provider-valid signatures, simulate retries, or provide replay reports required for audits; agencies will pay for client-project seats.

Why it doesn't exist yet

incumbent generic request-bin tools ignore provider-specific signature schemes, idempotency semantics, and real-world failure modes (retries, reordering, partial duplicates). Payment providers offer playgrounds that only send ideal events from their consoles, not configurable bad-network variants; a small indie can stitch signed-payload templates + replay scheduler + a simple verification harness and ship fast.

First users

the first 10 will be: (1) indie SaaS founders who've lost payments to webhook bugs, (2) small teams migrating to Stripe/PayPal who need regression tests, (3) agencies integrating e-commerce for clients, (4) open-source lib authors wanting CI tests — they get reproducible signed webhooks and a failing CI badge in minutes instead of hours.

Build size

2 people x 8 weeks (MVP: support Stripe+PayPal signed payload templates, replay scheduler, simple verification runner that checks 2xx+timing and idempotency handling; excludes building SDK libs for every language and enterprise SSO integrations).

Biggest risk

a payment provider ships a first-class signed-replay test API that covers configurable bad-network variants and is free/easier to use, or major infra providers add turnkey webhook-simulation into CI tools.

Conditions for a hit (all 3 required)

• Signed payload generator: given a chosen provider (Stripe or PayPal), event type, and JSON overrides, produce a request with correct provider signature headers that your endpoint will accept as genuine within a 10-second window.
• Replay variants: run a test batch of 20 events with configurable delays, duplicates, out-of-order delivery, network timeouts and exponential retry patterns; the system records timestamps and the exact raw requests sent.
• Verification report: for each test run, report whether endpoint returned 2xx within 3s for each event, whether idempotency keys were handled (duplicate suppression detected from response behavior), and a downloadable HAR + signed-request archive.

How it's judged (in 6 months)

Product Hunt daily top 5 OR GitHub repo reaches 1,000 stars (either qualifies)(judgment date 2027-02-16)

AI self-confidence 55/100 — self-reported likelihood of meeting the criterion, not a business success rate