May 2022 – May 2024 · 2 yrs · Paris, Île-de-France, France · Hybrid

• I worked on the Claims Processing module—the engine that handles insurance claims from submission to settlement.
• My role was to support the existing architecture and ship new features that helped streamline the process.
• The Backend: I worked across a hybrid stack, writing Node.js for the API logic and supporting the Rust services that handle the more performance-critical validation steps.
• Event Handling: Claims move through many states, so I worked with AWS Kinesis to stream these events in real-time, ensuring the status was always accurate across the system.
• Data: We used MongoDB to store the complex claim documents. I handled the query optimizations to make sure claim retrieval was fast for the adjusters.
• Visibility: Used Grafana and CloudWatch to monitor the health of the claims engine, helping us catch processing errors before they affected clients.

Nov 2020 – Feb 2022 · 1 yr 3 mos · Kyiv City, Ukraine · On-site

• Engineered a sophisticated “smart search” platform using Elasticsearch (v7.x), developing custom NLP-driven analyzers and ranking boosters to process complex botanical queries.
• Ensured sub-second response times during the massive 2020 pandemic-driven traffic surge.
• Introduced Rust-based performance modules for CPU-intensive query preprocessing and scoring logic, reducing latency under peak load.
• Designed and implemented a custom Horizontal Pod Autoscaler (HPA) controller for Kubernetes to handle instantaneous traffic spikes triggered by nationwide TV campaigns and telethons.
• Addressed the limitations of reactive cloud autoscaling by building a predictive orchestration layer that scaled backend services preemptively based on external marketing event triggers.
• Leveraged Rust and Go for low-latency scaling decision paths, ensuring millisecond-level reaction times.
• Maintained 100% system stability under 10x normal traffic load.
• Built high-performance microservices using Go and Node.js, with Rust integrated for performance-critical paths and resource-sensitive workloads.
• Standardized infrastructure provisioning using Terraform, ensuring reproducible, version-controlled AWS environments across all stages.
• Impact: Prevented cold-start delays and eliminated scaling bottlenecks during peak promotional windows, preserving checkout continuity and revenue during extreme traffic events.

Oct 2019 – Oct 2020 · 1 yr · Kyiv City, Ukraine · On-site

• Engineered a high-throughput, cloud-native backend powering the retailer’s flagship mobile application, leveraging Go (Golang) and Node.js for scalable service development.
• Designed services to thousands of active users with a strong focus on reliability and horizontal scalability.
• Orchestrated microservices deployment and lifecycle management using Kubernetes, enabling seamless rolling updates, autoscaling, and high availability across production environments.
• Standardized infrastructure provisioning with Terraform (Infrastructure-as-Code), replacing manual and ad-hoc setups with automated, version-controlled infrastructure definitions.
• Improved environment consistency and reduced operational drift across dev/stage/prod.
• Reduced latency and lowered server resource consumption for high-load endpoints.
• Designed and implemented resilient RESTful APIs tailored for mobile client performance, focusing on payload minimization, efficient data retrieval, and network-aware optimization.
• Contributed to the migration of legacy systems toward a modern microservices architecture, improving maintainability, deployment velocity, and team autonomy across services.

Apr 2016 – Sep 2019 · 3 yrs 5 mos · Kyiv City, Ukraine · On-site

• Led the development of the core mobile platform and supporting backend services, coordinating a cross-functional team of 8+ engineers (backend, mobile, QA, DevOps).
• Owned architectural decisions across mobile and backend layers, aligning delivery with business and product stakeholders.
• Initiated and led a strategic migration from REST to GraphQL, redesigning the API layer to support flexible data querying for React Native clients and third-party integrations.
• Reduced over-fetching and improved client-side performance through schema-driven data shaping.
• Introduced centralized schema governance and improved API evolution workflows.
• Designed and built a scalable AWS-based backend (Node.js), integrating with React Native mobile applications used by millions of travelers globally.
• Focused on availability, resilience, and backward compatibility with legacy enterprise systems.
• Implemented and standardized CI/CD pipelines for mobile and backend releases, significantly improving deployment reliability and accelerating release cycles.
• Reduced manual release overhead and improved production stability.

Apr 2014 – Apr 2016 · 2 yrs · Kyiv City, Ukraine · On-site

• Designed, developed, and maintained 10 production-grade microservices in Node.js and Rust within a large-scale enterprise travel platform.
• Built high-performance Rust modules for critical data validation and business rule enforcement, focusing on memory safety and execution efficiency.
• Contributed to backend systems handling complex booking flows and integrations with legacy enterprise infrastructure.
• Managed Infrastructure-as-Code using Chef and Ansible, maintaining consistent multi-environment deployments (dev/stage/prod).
• Worked on service reliability, deployment automation, and integration stability across distributed systems.

Jan 2013 – Jan 2015 · 2 yrs

• As an independent Web Developer participated in several projects of different complexity including:
• Implemented Node.js security scanner for one Chinese ISP. Automatic JavaScript analyzer with distributed architecture for detecting security vulnerabilities of AJAX and Web 2.0 applications such as SQL Injection and Cross-Site Scripting (XSS) and other known vulnerability issues.
• Created few web sites for various businesses and private parties using WordPress and PHP technologies including: http://grouprost.com/

Jan 2010 – Jun 2013 · 3 yrs 5 mos · Ukraine kiev

• Conducted business requirements elicitation sessions with customers.
• Fully translated gathered business requirements into Software Requirements Specification for responsible module and maintained it through the SDLC.
• Gathered, analyzed and documented requirements and constraints from regulators to ensure the solution is fully compliant with industry and government prescriptions.
• Participated in design sessions with developers to identify technological constraints and risks as well as provide subject matter expertise for developed module functionality.
• Performed regular solution validation through conducted module demo for internal and external stakeholders.
• Participated in developing training materials for technical support team in responsible area.