ChaseProof → Payment Callback Verify Debugger

One-click diagnosis for intermittently failing payment callbacks so indie devs stop losing orders

Problem

Online payments fail intermittently—about 1 in 10 callbacks throws signature mismatch—while local replay and production packet replay both pass. After three days it turns out a gateway strips a URL path prefix and the verifier re-joins timestamp after parsing, so the signed string differs. Indie devs and small teams have no systematic tool to compare raw payloads, middleware rewrites, and signed strings.

Solution

A local debug workbench: import the gateway's raw request capture and your verification code config, then automatically compare path, query params, timestamp units, empty-value handling, and concatenation order. It outputs a diff report and highlights middleware-modified fields. Ships with signature templates for common gateways (WeChat Pay, Alipay, Stripe, PayPal) and one-click regression tests.

Users

Indie developers, small-team backend engineers, and SaaS developers maintaining self-built payment systems.

MVP

Parse raw HTTP requests and reconstruct canonical signed string; support signature rule templates for common gateways; diff view highlighting rewritten fields; save and replay local test cases; one-click masking of sensitive fields

Revenue

Lifetime license $19–$39, or team seat subscription $99/year; optional marketplace commission on gateway templates.

Why now

AI-generated code accelerates shipping, and payment callback integrations are often accepted without rigorous testing; gateway rules are complex and docs scattered, big players ignore long-tail gateways, leaving room for indie builders.