Karthick Ramachandran

UK-based fintech providing mobile-first banking services for MSMEs.

I worked as part of the Acquiring Services team, working on payment acquisition across India, UK, and Germany.

• Designed and delivered key features including OTP verification & auditing, Instant QR code generation, Sales calculator, and risk-based limit enforcement - reducing chargebacks on Paylinks by 60%.
• Collaborated closely with product managers, operations, and third-party providers to ensure smooth cross-platform integrations.
• Mentored junior engineers and championed best coding and design practices across the team.
• Active member of the on-call incident response and reliability engineering communities.

Europe's leading online fashion platform, offering shoes, apparel, and beauty across 25 markets.

Part of the Fulfillment Core (Smart Inventories) team, responsible for systems that give customers an accurate view of available inventory across Zalando's and Partners' stock.

• Led the Future-Stock project, enabling customers to purchase assortments before they are physically in stock.
• Key member of the Inventory Ringfencing project, limiting stock offering per market and improving assortment quality by 30%.
• Part of the task force ensuring smooth operations during Cyber Week 2021 and 2022, including tech migration from legacy services.
• Mentored new joiners and junior developers on system architecture and processes.
• Involved in on-call incident response and hiring for the organisation.

South Korean multinational and global leader in consumer electronics, semiconductors, and mobile devices.

Part of the payments team that built and integrated with various payment gateways and microservices to enable customers to buy products from the Samsung e-commerce site.

• Implemented the MOTO (Mail Order/Telephone Order) payment option, enabling businesses to place orders via telephone.
• Contributed to the Single-Master project, consolidating multiple tenant repositories into one and improving test coverage across the codebase.

Indian SaaS company offering a suite of 45+ cloud-based business and productivity applications.

Worked on the Zoho Mail framework team.

• Reduced storage overhead by 50% in Hadoop clusters using Erasure coding.
• Increased throughput by 50% for sequence messages in internal messaging queue system.
• Implemented Ratio-Based partition technique for production server load customization.
• Created internal tools for runtime configuration of HBase clusters & messaging queues.