• Designed and implemented robust server-side APIs using NestJS and TypeScript, facilitating seamlessintegration with front-end systems and ensuring data security.• Developed a custom wrapper service for Google Cloud Datastore, significantly enhancing entitypopulation and projection capabilities. This innovation improved code readability, maintainability, andreduced development time for complex data operations.• Created a soft lock service to mitigate race conditions in order processing flows. This solutionoptimized resource utilization and prevented data conflicts, enhancing system reliability and performance.• Built a custom search and autocomplete solution leveraging Google Cloud Datastore's prefix searchfunctionality, eliminating the need for third-party search engines and reducing infrastructure costs.• Constructed a pricing hierarchy system based on user roles, implementing complex discountcalculations according to internal business logic. This system ensured accurate, role-based pricing acrossthe platform.• Integrated third-party services, including Mintroute, to expand system capabilities and meet evolvingbusiness needs.• Actively participated in code reviews, GitHub issue tracking, and agile development processes,contributing to code quality and team efficiency.• Consistently refactored and optimized codebase, focusing on performance enhancements andimproved code readability, resulting in more maintainable and scalable applications.