# Oleksandr Fedyk > Software Engineer at HaydenAi Location: San Francisco, California, United States Profile: https://flows.cv/oleksandrfedyk Senior Software Engineer with over 4 years of experience delivering high-performance backend solutions and driving digital transformation across various industries. At Amadev, I’ve grown from a Junior to a Senior role, specializing in scalable microservices, cloud infrastructure, and data integration using modern technologies like Java(J2EE), Python, Spring Boot, Apache Spark, SQL, and AWS. In my current role, I’ve led multiple projects that optimized business processes, reduced operational costs, and improved system performance. I take pride in creating robust, scalable systems and driving measurable business results. Key Achievements: • Developed a microservices architecture to automate power grid connections using Java, Spring Boot, RabbitMQ, Apache Kafka, and Redis, supporting over 250,000 daily transactions and reducing API response times by 35%. • Built a data comparison microservice using Python, SQLAlchemy, Pandas, and Apache Spark to process datasets exceeding 700,000 rows, reducing comparison time by 40%. • Designed and deployed scalable cloud infrastructure using Kubernetes, AWS EC2, S3, and RDS to improve system availability, reduce downtime, and optimize resource utilization by 20%. • Optimized report generation processes, reducing generation time from 10-15 minutes to 10-15 seconds, a 60x improvement, by implementing a SQL-based solution and deploying it as a separate service. • Integrated with the postal service REST API, automating the generation and dispatch of outgoing correspondence. This reduced 4-5 hours of manual work to just minutes and improved the process by over 150 times. • Implemented a SOAP-to-REST proxy server to bridge legacy systems with modern APIs, reducing data exchange time by 40% and improving reliability. • Built and managed CI/CD pipelines using GitLab, automating code quality checks, reducing manual review time by 70%, and accelerating time to market by 50%. • With deep experience in SQL (MS SQL, PostgreSQL) and NoSQL databases (MongoDB, Redis, DynamoDB), I ensure systems can handle both structured and unstructured data efficiently. I’m passionate about building reliable, secure, and scalable backend systems that drive business success. Holding a Bachelor’s in Computer Science from Lviv Polytechnic National University, I am continuously exploring new technologies to stay at the forefront of the software engineering field. Let’s connect to discuss how my expertise can help you achieve your next big initiative. Email: oleks.fedyk@gmail.com ## Work Experience ### Software Engineer @ Hayden AI Jan 2025 – Present | San Francisco, California, United States ### Senior Software Engineer @ AmaDev Jan 2021 – Jan 2025 • Implemented an efficient correspondence dispatch process, integrating Java Enterprise Edition, Spring Framework, and MS SQL Database; achieving a remarkable 150% acceleration and streamlining of communication for the staff. •Designed and implemented scalable microservices architecture with Docker and Kubernetes using Spring Boot, enabling seamless integration between systems and reducing API response times by 35%, while supporting over 250,000 daily transactions. • Integrated Apache Kafka and Kafka Streams for efficient monitoring of load on the power grid, enabling real-time processing and analysis. This improved reliability and accelerated operations by 25% during new electrical grid connections and user notifications. • Deployed scalable cloud infrastructure on AWS (EC2, RDS, S3, EKS), optimizing resource allocation and reducing operational costs by 18%. Enhanced performance with asynchronous processing using RabbitMQ, reducing latency by 30% and cutting cloud costs by 20%. • Implemented data caching using Redis and integrated ElasticSearch for indexing and querying report data, resulting in an 85% faster report generation process and improved search performance. This enhancement significantly boosted user experience and reduced server load during peak times. • Led and coordinated a team of 8 Java developers, utilizing Java 21, Spring Framework, and NoSQL Mongo DB to deliver a successful project. Achieved significant performance improvements, including a 20% increase in system efficiency and a 30% reduction in database query response time. • Implemented Test-Driven Development (TDD) practices across the development lifecycle, enhancing code quality and reducing bugs by 35%. This improved team efficiency by 25% and accelerated feature delivery timelines by 20%. • Spearheaded the integration of GitLab into the CI/CD pipeline, automating code quality checks and reducing manual review time by 70%, resulting in a 50% faster time to market. ### Software Engineer @ AmaDev Jan 2020 – Jan 2021 • Automated seamless integration of new subscribers into the electrical grid, facilitating connections for over 150,000 consumers annually, optimizing the grid connection procedure, and increasing annual revenue by $4 million. • Developed a system for integration with a postal service, accelerating data transfer for outgoing correspondence by 95%. Leveraged technologies such as Spring Boot, RESTful APIs, and RabbitMQ to ensure reliable and efficient communication, reducing processing time and enhancing operational workflows. • Developed and maintained comprehensive unit and integration test suites using JUnit and Mockito, achieving 90% test coverage and reducing production bugs by 35%, significantly enhancing system reliability and deployment confidence. • Optimized performance of Java applications by integrating Spring, Hibernate, and Maven, resulting in a 30% reduction in database query execution time and a 25% improvement in system scalability. • Guided skill enhancement initiatives, and conducted code reviews, resulting in a 15% acceleration in project delivery by reducing the development timeline by 2 weeks. Implemented Scrum and Agile Methodologies to optimize team productivity and drive efficient collaboration. ### Wordpress Developer @ Freelance (Self employed) Jan 2017 – Jan 2020 Developed 30+ web projects using HTML, CSS, HTML, and JavaScript. Completed all projects on schedule and budget, and 97% of desired functionality. TOP 3 projects: Project: Custom Membership Plugin Development. Developed a custom membership plugin for a client's WordPress website, enabling subscription-based access to premium content. Accomplishments: 1) Engineered a robust plugin integrating subscription plans, user authentication, and content restriction functionalities. 2) Implemented payment gateway integrations (Fondy/LiqPay) resulting in a 40% increase in premium content subscriptions. Project: Dynamic Events Calendar Plugin. Designed and built a dynamic events calendar plugin for a community-based WordPress website, facilitating event creation, RSVPs, and calendar display. Accomplishments: 1) Customized and integrated the plugin with existing WordPress themes, allowing event organizers to manage and showcase events efficiently. 2) Enhanced user experience, resulting in a 50% increase in event attendance and engagement. Project: WooCommerce Custom Product Configurator Plugin. Led the development of a custom product configurator plugin for an e-commerce WordPress site, allowing customers to personalize products. Accomplishments: 1) Engineered a configurable plugin enabling customers to personalize products with multiple options (colors, sizes, features). 2) Improved user interaction, resulting in a 30% increase in average order value and customer satisfaction. ## Education ### Bachelor's degree in Computer Science Lviv Polytechnic National University ## Contact & Social - LinkedIn: https://linkedin.com/in/oleksandr-fedyk --- Source: https://flows.cv/oleksandrfedyk JSON Resume: https://flows.cv/oleksandrfedyk/resume.json Last updated: 2026-04-10