Backend Developer

OrderHub

E-commerce order & payment operations

2024 — 2025·4 engineers

0k+

orders / month

99.98%

webhook processing success

−0%

reconciliation time

<0ms

p95 API latency

Overview

An order and payment operations platform for an e-commerce business: order lifecycle management, Stripe payment integration, inventory synchronization, webhook processing, and automated reconciliation between payments and orders.

Challenges

Stripe webhooks arriving out of order, duplicated, or during downtime windows.
Manual payment-order reconciliation consumed a full workday each week.
Inventory oversells during flash-sale traffic spikes.

Solutions

Built idempotent webhook processing with an event-log table, signature verification, and RabbitMQ-backed replay for missed events.
Automated daily reconciliation jobs matching Stripe balance transactions against order records, flagging only true mismatches for humans.
Guarded inventory with transactional reservations in PostgreSQL and Redis-based hot-SKU counters.

Results

99.98% webhook processing success across 30k+ monthly orders.
Reconciliation effort cut ~80% — from a weekly workday to a 90-minute review.
p95 API latency under 150ms through checkout peaks; oversells eliminated.

Architecture

Tech stack

Node.js
NestJS
PostgreSQL
Redis
RabbitMQ
Stripe API
Docker
AWS

Process

01
Payment flow design
2 weeks
Modeled order states, payment events, and reconciliation rules.
02
Integration build
5 months
Stripe integration, webhook pipeline, inventory guards.
03
Automation
2 months
Reconciliation jobs and ops dashboards.

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