About Sergei
English
Native or bilingual
Experience
- (Millennium Corporation|Senior Full Stack DeveloperSeptember 2022 - March 2025 (2 years and 6 months)Arlington County, Arlington, VA, USA• Developed a scalable Motor-Mart project using React.js and Go microservices, supporting thousands of concurrent users.• Integrated Apache Kafka and RabbitMQ to enable reliable, asynchronous, event-driven architecture, reducing system bottlenecks.• Optimized API latency by 40% by refactoring routes with Gorilla Mux and streamlining middleware in Gin.• Built and deployed CI/CD pipelines with GitHub Actions and Docker, reducing release times by 60%.• Mentored 5 junior developers and led system architecture redesign, accelerating feature delivery cycles by 30%.
- (InnovativeSoftware Solutions, IncFull Stack DeveloperNovember 2020 - January 2022 (1 year and 2 months)San Antonio, TX, USA• Spearheaded migration from legacy Java monolith to modern Golang microservices with React, reducing load times by 50%.• Designed RESTful and Graph QL APIs for user and admin portals, increasing client integration success rate by 40%.• Improved frontend responsiveness by using React Hooks, enhancing UX and reducing re-renders by 35%.• Led Elasticsearch integration that powered complex filters and improved search speed from 2.3s to <500ms for datasets exceeding 12M records.• Acted as sprint tech lead, facilitating planning and peer reviews to ensure quality and delivery on time.
- Remote (Intrado CorporationSoftware DeveloperJune 2017 - August 2020 (3 years and 2 months)Omaha, NE, USA• Analyzed internal dashboards and reporting tools in React.js and Node.js, boosting data visibility across departments.• Designed optimized database schemas and SQL queries in PostgreSQL, reducing report generation time by 70%.• Developed mobile backend services in Go using Echo, supporting scalable push notifications and user analytics.• Partnered with UX designers to deliver mobile-first, responsive UIs aligned with brand standards.• Deployed dev/staging environments using Docker and Terraform, improving team onboarding efficiency by 50%.
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Education
- Bachelor's Degree in Computer ScienceUniversity of Belgrade2015Bachelor's Degree in Computer Science
- AWS Certified Solutions Architect2023AWS Certified Solutions Architect