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I am a Senior Software Engineer with 10+ years building production-grade systems. I specialize in Java, Spring Boot, Rails, Node.js, TypeScript, and Python across cloud-native and AI-driven environments. I design Rails 7 backends with clean domain boundaries, resilient background processing, real-time updates, and smart caching. I have hands-on experience with microservices, RESTful APIs, and distributed systems on AWS and GCP. I enjoy turning complex requirements into scalable architectures and leading teams to deliver measurable business value. My focus includes AI/LLM engineering with deterministic workflows, prompt orchestration, and model integration using Cohere, plus frontend work with React, Next.js, and Angular. I advocate for clean architecture, automation, and developer experience, and I like shipping secure, high-performance systems that scale globally. I thrive in cross-functional collaboration and mentoring engineering teams.…I am a Senior Software Engineer with 10+ years building production-grade systems. I specialize in Java, Spring Boot, Rails, Node.js, TypeScript, and Python across cloud-native and AI-driven environments. I design Rails 7 backends with clean domain boundaries, resilient background processing, real-time updates, and smart caching. I have hands-on experience with microservices, RESTful APIs, and distributed systems on AWS and GCP. I enjoy turning complex requirements into scalable architectures and leading teams to deliver measurable business value. My focus includes AI/LLM engineering with deterministic workflows, prompt orchestration, and model integration using Cohere, plus frontend work with React, Next.js, and Angular. I advocate for clean architecture, automation, and developer experience, and I like shipping secure, high-performance systems that scale globally. I thrive in cross-functional collaboration and mentoring engineering teams.

Kornel Kedzior

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

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I am a Senior Software Engineer with 10+ years building production-grade systems. I specialize in Java, Spring Boot, Rails, Node.js, TypeScript, and Python across cloud-native and AI-driven environments. I design Rails 7 backends with clean domain boundaries, resilient background processing, real-time updates, and smart caching. I have hands-on experience with microservices, RESTful APIs, and distributed systems on AWS and GCP. I enjoy turning complex requirements into scalable architectures and leading teams to deliver measurable business value. My focus includes AI/LLM engineering with deterministic workflows, prompt orchestration, and model integration using Cohere, plus frontend work with React, Next.js, and Angular. I advocate for clean architecture, automation, and developer experience, and I like shipping secure, high-performance systems that scale globally. I thrive in cross-functional collaboration and mentoring engineering teams.…I am a Senior Software Engineer with 10+ years building production-grade systems. I specialize in Java, Spring Boot, Rails, Node.js, TypeScript, and Python across cloud-native and AI-driven environments. I design Rails 7 backends with clean domain boundaries, resilient background processing, real-time updates, and smart caching. I have hands-on experience with microservices, RESTful APIs, and distributed systems on AWS and GCP. I enjoy turning complex requirements into scalable architectures and leading teams to deliver measurable business value. My focus includes AI/LLM engineering with deterministic workflows, prompt orchestration, and model integration using Cohere, plus frontend work with React, Next.js, and Angular. I advocate for clean architecture, automation, and developer experience, and I like shipping secure, high-performance systems that scale globally. I thrive in cross-functional collaboration and mentoring engineering teams.

Available to hire

I am a Senior Software Engineer with 10+ years building production-grade systems. I specialize in Java, Spring Boot, Rails, Node.js, TypeScript, and Python across cloud-native and AI-driven environments. I design Rails 7 backends with clean domain boundaries, resilient background processing, real-time updates, and smart caching. I have hands-on experience with microservices, RESTful APIs, and distributed systems on AWS and GCP. I enjoy turning complex requirements into scalable architectures and leading teams to deliver measurable business value.

My focus includes AI/LLM engineering with deterministic workflows, prompt orchestration, and model integration using Cohere, plus frontend work with React, Next.js, and Angular. I advocate for clean architecture, automation, and developer experience, and I like shipping secure, high-performance systems that scale globally. I thrive in cross-functional collaboration and mentoring engineering teams.

Skills

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Intermediate

Work Experience

Senior Java Full-Stack Engineer at Andersen

June 1, 2024 - Present

Led the development of an enterprise-grade financial services platform using Java and Spring Boot, delivering highly available microservices for real-time transaction processing. Designed RESTful APIs handling over 2 million daily requests with sub-200ms latency. Built a GraphQL gateway to aggregate Rails and service endpoints, adding schema checks and contract tests. Hardened auth: aligned SPA session handling with Rails (Devise/Doorkeeper), added refresh-token rotation, device trust, and step up verification for sensitive actions. Security posture improved with no critical findings in pen tests. Built scalable frontend modules using React and TypeScript, improving user workflow efficiency by 30%. Introduced cloud-native patterns on AWS, including containerized deployments with Docker, reducing release cycles by 40%. Optimized database queries in PostgreSQL, cutting average response time by 25%. Collaborated with product managers and architects to translate business requirements into

AI / Full Stack Engineer at Cohere

October 1, 2022 - April 1, 2024

Developed AI-powered backend services integrating large language models using Python, Node.js, and TypeScript for enterprise clients. Migrated a Rails monolith toward API-first boundaries consumed by new SPAs (React for client onboarding, Vue 2 for admin tools, Angular 7 for reporting). Implemented secure payment and KYC/AML flows with Rails controllers and webhooks; enforced idempotency, replay protection, and tamper evident audit trails. Implemented deterministic LLM workflows to ensure predictable and auditable AI outputs in production systems. Built scalable REST APIs supporting AI inference pipelines with over 99.9% uptime. Deployed cloud infrastructure on GCP and AWS, optimizing inference costs by approximately 35%. Created responsive frontend dashboards using React to visualize model outputs and usage analytics. Containerized AI services using Docker, enabling rapid experimentation and deployment. Collaborated with research teams to productionize experimental LLM features. Deliv

Backend Developer at Shopify

July 1, 2017 - August 1, 2020

Engineered high-throughput e-commerce backend services using Java, Node.js, and Spring Boot supporting millions of merchants. Designed microservices handling payments, inventory, and order management at global scale. Integrated multiple databases including PostgreSQL, MySQL, and MongoDB for different workload patterns. Improved API performance by 40% through caching strategies and query optimization. Implemented background processing and async workflows using Go and Python services. Maintained and extended legacy systems in C# and .NET, ensuring backward compatibility. Participated in on-call rotations, maintaining high system reliability and availability. Delivered a real-world checkout optimization project that increased conversion rates by 12%.

Frontend Engineer at Shopify

November 1, 2015 - July 1, 2017

Built complex merchant-facing web applications using React, TypeScript, and Angular. Developed reusable UI components and state management solutions to support large product teams. Optimized frontend performance, reducing initial load times by 25%. Collaborated closely with backend teams to design consistent API contracts. Implemented automated testing using Jest, improving release stability. Contributed to mobile features using React Native. Ensured cross-browser compatibility and accessibility compliance. Delivered a real-world merchant analytics dashboard used by thousands of sellers daily.

Junior Frontend Developer at Jobber

May 1, 2014 - October 1, 2015

Engineered customer-facing web interfaces; component-based UI architectures; responsive design using Tailwind CSS; integrated REST APIs; improved UI maintainability; collaborated with designers to translate UX mockups into production code; delivered a real-world scheduling interface used by service professionals.

Frontend Developer Intern at Jobber

November 1, 2013 - May 1, 2014

Assisted in developing responsive web pages; built interactive UI components; integrated REST APIs; learned component-based architecture and agile practices; delivered an internal admin dashboard.