Marcin N.

Software Engineer

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Szarlejka, Poland

Experience

Jan 2024 - Jul 2025
1 year 7 months

Software Engineer

Megaverse

  • Designed a microservices-based architecture using Ruby on Rails, Sidekiq, and PostgreSQL, deployed with GCP Cloud Run for horizontal scalability.
  • Developed modular React components using TypeScript, Next.js, Tailwind CSS, Material UI, and Framer Motion, improving frontend maintainability by 35%.
  • Integrated GraphQL APIs via GraphQL-Ruby and optimized data fetching with Apollo Client for real-time and paginated queries.
  • Implemented Redis caching and Pub/Sub messaging with ActionCable to reduce API response times.
  • Built real-time dashboards with WebSockets, Socket.io, and dynamic charts using Chart.js and D3.js.
  • Configured CI/CD pipelines with GitHub Actions and GCP Cloud Build, achieving automated testing, linting, and zero-downtime deployments.
  • Implemented unit and integration tests using Jest, Supertest, and React Testing Library for reliable production code.
  • Optimized frontend performance using lazy loading, code splitting, memoization, and Next.js SSR/ISR strategies.
  • Collaborated with designers and backend engineers to implement WCAG-compliant accessibility and cross-browser responsive layouts.
  • Managed cloud infrastructure, monitoring, and logging using GCP Stackdriver, Cloud Monitoring, and Prometheus/Grafana dashboards.
Feb 2022 - Dec 2023
1 year 11 months

Full Stack Engineer

Emagine

  • Led development of a multi-tenant SaaS application using React, Redux Toolkit, TypeScript, and Ruby on Rails, serving enterprise clients with real-time analytics dashboards.
  • Migrated legacy monolithic architecture to AWS microservices, orchestrated via ECS Fargate, CloudFormation, and AWS Lambda with Rails serverless adapters for background processing.
  • Built REST APIs and integrated GraphQL endpoints using Rails API mode and GraphQL-Ruby, connecting multiple internal and external services including Stripe, PayPal, Twilio, and SendGrid.
  • Implemented Next.js server-side rendering (SSR) and incremental static regeneration (ISR) for faster content delivery and SEO optimization.
  • Designed complex PostgreSQL and MongoDB schemas, optimized indexing strategies, and created Redis caching layers to accelerate query performance.
  • Automated CI/CD pipelines using GitHub Actions, AWS CodePipeline, and Docker containers, reducing deployment times by 50%.
  • Introduced unit testing with Jest, API testing with Supertest, and end-to-end testing with Cypress, maintaining over 85% code coverage.
  • Integrated AWS S3, CloudFront, and Lambda for scalable file storage and CDN distribution of static assets.
  • Secured applications using Devise, JWT, and Pundit for role-based access controls, enforcing enterprise-grade authentication and authorization.
  • Configured real-time event handling with WebSockets, Socket.io, and AWS SNS/SQS for notifications and background processing.
  • Refactored legacy JavaScript to TypeScript, introducing strong typing and reducing runtime errors in production.
  • Implemented logging and observability using AWS CloudWatch, Sentry, and ELK stack for system monitoring.
  • Mentored junior developers, conducted code reviews, and enforced modular architecture principles and best practices across the team.
Jan 2020 - Jan 2022
2 years 1 month

Full Stack Developer

Donatix

  • Developed responsive SPAs using React, Next.js, TypeScript, Styled Components, Material UI, and Tailwind CSS, achieving a 100% Lighthouse accessibility score.
  • Built secure backend APIs with Ruby on Rails, Devise, JWT authentication, and Rack::Attack for rate limiting, serving millions of users.
  • Integrated GraphQL endpoints via GraphQL-Ruby for flexible, efficient data retrieval across multiple client applications.
  • Managed frontend state with Redux, Zustand, and React Query, enabling optimized asynchronous data handling.
  • Designed and optimized PostgreSQL and MongoDB database models for high-traffic applications, supporting millions of records.
  • Implemented Dockerized environments for development, staging, and production to ensure consistency.
  • Automated infrastructure provisioning with AWS CloudFormation and Terraform, enabling reliable deployment and scaling.
  • Developed background job processing using Sidekiq and Redis for emails, notifications, and reporting tasks.
  • Deployed containerized services to AWS ECS Fargate with auto-scaling and zero-downtime deployment strategies.
  • Created internal dashboards with React and Ant Design, displaying real-time analytics, logs, and operational metrics.
  • Integrated Stripe, PayPal, and webhooks for complete payment workflows, including subscription and refund handling.
  • Enforced coding standards with ESLint, Prettier, and comprehensive API documentation with Swagger/OpenAPI.
  • Actively participated in Agile ceremonies, sprint planning, backlog grooming, and team retrospectives to ensure timely delivery.
Jul 2017 - Dec 2019
2 years 6 months

Junior Full Stack Developer

Luvina Software

  • Built and maintained enterprise web applications with React.js, Ruby on Rails, and MySQL, delivering maintainable and efficient solutions.
  • Developed forms, validations, and CRUD operations using Ruby on Rails controllers, ActiveRecord models, and strong parameters, connecting frontend and backend efficiently.
  • Integrated external APIs and internal services, ensuring smooth data exchange across multiple platforms.
  • Wrote unit tests and conducted debugging, supporting consistent functionality across development and production environments.
  • Documented workflows, set up Jenkins pipelines, and supported team adoption of CI/CD best practices.
  • Gained strong foundational experience in full stack development, agile collaboration, and modern development practices.

Summary

Full Stack Engineer with 7 years of experience building scalable React and RoR applications and cloud-native solutions on AWS and GCP. Skilled in microservices, REST/GraphQL APIs, real-time features, and modern DevOps practices, delivering high-performance, secure, and maintainable web applications.

Languages

Vietnamese
Native
English
Advanced

Education

Oct 2012 - Jun 2016

Tan Tao University

Bachelor’s Degree · Computer Science · Viet Nam

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