ryanzhang

• Led backend development of a Custodian crypto-asset custody platform; designed and implemented end-to-end deposit/withdrawal and asset-sweep flows for both hot and cold wallets. Platform peak custodied assets reached 1,200 BTC. • Built PayCrypto-Checkout, a crypto payment solution supporting both custodial and non-custodial payment modes. Monthly payment order volume peaked at 1.5M USDT. • Developed PayCrypto-Teams, a crypto prepaid-card product; shipped the full business pipeline covering KYC, card issuance, top-up, offline spending, and asset sweep. Monthly card transaction volume peaked at 1M USDT.

• Developed a multi-phase medical quality-control platform across three release cycles — built imaging QC (Phase 1), pathology QC (Phase 2), and medical-record QC (Phase 3), and delivered private microservice deployment for hospital on-premise environments. • Iterated the Sanofi patient-engagement program from v1.0 through v2.10; built and owned the user center, scaling registered patients from zero to 130,542.

• Migrated 80 million product reviews to international e-commerce sites, enriching overseas review content and driving a 98% MoM increase in review page dwell time. • Built core scheduled-job modules for a supplier marketing platform (baby & maternity category) — owned the full lifecycle from project scaffolding to production deployment. • Resolved a critical data-integrity issue in the PMS procurement system that was blocking product inbound; independently diagnosed the root cause and shipped the fix.