Yuwei Liang
Summary
Software engineer with 10+ years building production e-commerce, marketplace, payments, and billing systems. At Cart.com, I develop OMS/WMS inventory and make high-risk changes safer through production measurement, characterization testing, and observability. I also build mutation-testing and AI delivery safeguards that verify changes and tests behave as intended.
Experience
Cart.comFeb 2026 – Present
Software Engineer, WMS Inventory & MarketplaceRemote
- Inventory Integrity: Investigated negative inventory across fulfillment centers and shaped the team's deduct-on-pick design after measuring concurrent batch behavior and ruling out location locking.
- Safe Change & Measurement: Delivered characterization suites, ledger attribution without changing a high-volume legacy table, and a facility scorecard to guide safe remediation.
- Inbound Inventory: Owned and deployed an inbound-PO ship-complete hold in a Django OMS/WMS, improving order consolidation for clients waiting on inbound stock. Added a regression proof that caught a release-loop defect before production.
- Lot Integrity: Added shadow telemetry and shadow-first cross-SKU lot validation at the inventory save layer for a lot-controlled client, targeting wrong-lot shipment defects.
- Production Reliability: Improved production observability by correcting ineffective metric-monitor configuration and validating telemetry delivery; identified asynchronous processing and data-pipeline reliability gaps.
- Vendor Payouts: Designed and shipped a marketplace vendor payout system end-to-end, supporting vendor disbursements after launch.
- Vendor Integration Reliability: Maintained vendor EDI integrations, diagnosing data and mapping issues to keep partner transactions flowing.
- Test Verification: Built an automated mutation-testing harness that verifies regression suites catch introduced defects.
- AI Delivery Standards: Turned an AI-assisted delivery postmortem into red-first verification guidance and agent-contract safeguards for future changes.
Houzz, Inc. — Marketplace2018 – Feb 2026
Full Stack Software EngineerLos Angeles, CA
- Checkout & Payments: Re-architected order creation to improve API responsiveness and integrated Apple Pay Express Checkout for mobile web, contributing to growth on that checkout surface.
- Billing & Accounting: Built a TIN/EIN tax-compliance system integrated with NetSuite to help marketplace partners meet IRS requirements; recovered overpaid sales tax through an Avalara API integration.
- Payment Terms: Led a multi-term payment system that reduced engineering involvement in net-term setup; shipped a quick-pay incentive to improve contribution margin.
- Product Ads: Diagnosed and fixed a Google Ads conversion-tracking issue, restoring reliable campaign measurement and enabling data-driven optimization.
- Supplier BI: Led engineering of a supplier-insight reporting platform with sales, inventory, and ads analytics.
Zobrist Consulting Group2015 – 2018
Software DeveloperLos Angeles, CA
- Led development of Mobilecom, a SaaS mobile-first storefront for IBM WebSphere Commerce, helping client sites improve the mobile shopping experience.
Projects
LoopiiMar 2026 – Present
Festival companion app — Coachella 2026
- Solo-Built & Shipped: Designed, built, and shipped Loopii — a React Native (Expo) iOS app — solo from zero to TestFlight in ~6 weeks, used by a private squad on the ground at Coachella 2026 W2.
- Claude-Driven UX: Drove the entire UX system — screens, navigation, day/night theming with 4 colorways, component composition — with Claude as the design partner, iterating on AI-generated design previews before translating to React Native.
- AI & Release Engineering: Integrated a Claude-powered in-app FAQ assistant and artist-recommendations engine; automated TestFlight delivery with Fastlane (auto-version bump, build, upload, GitHub release) behind a one-command deploy.
Technical Skills
Languages: Java, Python, JavaScript/TypeScript, PHP, SQL
Backend: REST/GraphQL APIs, microservices, distributed systems, event-driven architectures, query optimization, Node.js
Frontend & Mobile: React, Redux, React Native (Expo), HTML5, CSS3, responsive web
Data & Storage: MySQL, Postgres, Snowflake, Redis, DynamoDB, Elasticsearch, Solr, data pipelines
Cloud, DevOps & Observability: AWS (Lambda, DynamoDB, S3, API Gateway), Firebase (Firestore, Cloud Functions, Auth), Kubernetes, Docker, Terraform, CI/CD, Datadog, Grafana, on-call rotation
Integrations: NetSuite, Avalara/AvaTax, Stripe, Plaid, Apple Pay, Google Ads
AI & Developer Tooling: Claude Code, agentic development workflows, agent contracts and capability guards, LLM-assisted code review, MCP servers
Testing & Change Safety: characterization testing, golden-master suites, mutation testing, Playwright, pytest, Django test framework
Education
M.S., Software Engineering University of California, Irvine
2015B.S., Information Security Beijing University of Posts and Telecommunications
2013