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I'm a Senior Software Engineer with 7+ years building full-stack products end to end, specializing in backend APIs, real-time systems, and user-facing apps using TypeScript, React/Next.js, Node/Nest, Go, and PostgreSQL on AWS.\n\nI've shipped features for high-scale production systems (Cisco Webex ~8B calls/month). I focus on performance, reliability, and revenue impact, delivering integrations and improvements that cut page load times, reduce incident-resolution time, and uplift revenue.…I'm a Senior Software Engineer with 7+ years building full-stack products end to end, specializing in backend APIs, real-time systems, and user-facing apps using TypeScript, React/Next.js, Node/Nest, Go, and PostgreSQL on AWS.\n\nI've shipped features for high-scale production systems (Cisco Webex ~8B calls/month). I focus on performance, reliability, and revenue impact, delivering integrations and improvements that cut page load times, reduce incident-resolution time, and uplift revenue.

Oleksii Bondar

Full Stack Developer, Back-End Developer, Front-End Developer, +2

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I'm a Senior Software Engineer with 7+ years building full-stack products end to end, specializing in backend APIs, real-time systems, and user-facing apps using TypeScript, React/Next.js, Node/Nest, Go, and PostgreSQL on AWS.\n\nI've shipped features for high-scale production systems (Cisco Webex ~8B calls/month). I focus on performance, reliability, and revenue impact, delivering integrations and improvements that cut page load times, reduce incident-resolution time, and uplift revenue.…I'm a Senior Software Engineer with 7+ years building full-stack products end to end, specializing in backend APIs, real-time systems, and user-facing apps using TypeScript, React/Next.js, Node/Nest, Go, and PostgreSQL on AWS.\n\nI've shipped features for high-scale production systems (Cisco Webex ~8B calls/month). I focus on performance, reliability, and revenue impact, delivering integrations and improvements that cut page load times, reduce incident-resolution time, and uplift revenue.

Available to hire

I’m a Senior Software Engineer with 7+ years building full-stack products end to end, specializing in backend APIs, real-time systems, and user-facing apps using TypeScript, React/Next.js, Node/Nest, Go, and PostgreSQL on AWS.\n\nI’ve shipped features for high-scale production systems (Cisco Webex ~8B calls/month). I focus on performance, reliability, and revenue impact, delivering integrations and improvements that cut page load times, reduce incident-resolution time, and uplift revenue.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Advanced

Polish

Advanced

Ukrainian

Fluent

Russian

Fluent

Work Experience

Software Engineer at Cisco Systems (Webex)

January 1, 2025 - May 1, 2026

Debugged and resolved reliability issues across frontend, backend, and real-time service boundaries under live production traffic; repaired simulcast negotiation/fallback, improving video quality under fluctuating bandwidth. Designed VDI-aware Step Away / Auto-Away React flows and added telemetry, observability, and automated test coverage, contributing to a ~40% reduction in incident-resolution time.

Software Engineer at Circle K (Alimentation Couche-Tard)

August 1, 2022 - January 1, 2025

Built full-stack enterprise apps and a centralized authentication platform reused across multiple products, improving secure access and cross-system integration. Cut page load time ~20% through caching and efficient data access; delivered a banking integration contributing a ~15% revenue uplift with multi-language support. Reduced new-product integration time ~40% via REST API design, reusable service boundaries, and secure legacy-system modernization.

Full-Stack Software Engineer at Freelance / Independent

May 1, 2019 - June 1, 2022

Delivered responsive websites and custom web apps with React, Node.js, and PostgreSQL; gathered requirements directly from international clients and shipped across the full stack.