$50  / per hour

Years of experience



I am a highly experienced and versatile technology professional with a dual Master’s degree in Computer & Telecommunication Engineering and Economics - Management & Marketing Studies. Over my career, I have developed a deep expertise in software engineering with a strong emphasis on Ruby on Rails, leading and architecting innovative solutions across various sectors including IoT, cloud infrastructure, and virtual server management. My technical skill set spans a wide array of programming languages and technologies, including Ruby, Rails, React, Redux, and extensive experience with AWS services. As a proactive leader, I have consistently demonstrated the ability to manage dynamic teams, developing complex, scalable software systems that drive business efficiency and growth. My role as a Team Lead and Senior Developer has been marked by a commitment to excellence, innovation, and a hands-on approach to solving challenging problems. I thrive in environments that require both technical acumen and strategic thinking, leveraging my diverse background to contribute to successful project outcomes and business transformations. Whether architecting serverless backends or leading cutting-edge development projects, my goal is to deliver robust, high-performance solutions that meet and exceed the evolving demands of the digital landscape.

Tech Stack

Ruby on Rails, Docker, HTML, React, SQL, Web Development


  • System Design and Implementation: Fully responsible for designing and implementing complex systems using software design patterns and best practices in Ruby on Rails. Ensure security through JWT and utilize service-oriented architecture with serverless backends.
  • Continuous Integration and Continuous Deployment (CI/CD): Develop and maintain CI/CD pipelines using Docker, ECS, Elastic Beanstalk, and other AWS technologies to facilitate blue-green deployments and ensure high availability and minimal downtime.
  • Front-end Development: Implement single-page applications (SPA), responsive designs, and progressive web apps using React/Redux. Ensure these applications are fully tested using tools like Jest and Enzyme to maintain high-quality user experiences.
  • Service Integration: Integrate multiple services by leveraging AWS components such as IoT, Cognito, ECS, Lambda, SNS, SQS, and more, ensuring seamless interaction between different system elements and external interfaces.
  • Real-Time Security Solutions: Implement real-time, secure websocket solutions working in a multi-tenant environment. Maintain security using VPS, AWS policies, JWT, and AWS signature and certificates.
  • API Development and Management: Design and implement REST API interfaces, integrating frameworks like Grape with Rails. Manage API security with token-based authentication and adaptive calls throttling.
  • Team Leadership and Mentorship: Manage and mentor a team of developers, providing technical knowledge support, promoting best practices, and overseeing project progress to ensure alignment with business goals.

Employment history

Team Lead RoR/React Developer – Sixeye.net April 2017- Present

-Team lead developer of the remote management system for IoT devices.
-Combining the management and control of devices from different manufacturers into one multi-tenant portal with personalized branding.
-Managing and mentoring 6 people team of developers.
– Fully responsible for system design and implementation based on software design patterns.
Security based on JWT. Tokens changed after each request. SOA based serverless backend.
React/Redux frontend client.
– CI/CD, blue – green deployment system leveraging Docker, ECS, Elastic Beanstalk and other
AWS technologies
– Implementing SPA, responsive, PWA, front-end, React/Redux app, fully tested using Jest/
– Integrating multiple services leveraging AWS elements: IoT, Cognito, ECS, Lambda, SNS,
SQS, Load Balancer, VPS, Route53, EC2, S3, RDS, DynamoDB, CloudWatch, ElasticCache,
CloudFront, S3, Beanstalk, API, WAF
– Implementing real-time, fully secure, websocket solution working In multi-tenant environment.
Security based on VPS, AWS policies, JWT, AWS signature and certificates.
– External interface leveraging JSON API standard.

Senior RoR/JS Developer – Cloud.net / OnApp January 2015-March 2017

-Lead full stack developer of the virtual servers’ global deployment, provisioning and management system, allowing users to operate globally distributed cloud topologies from one web console.
-Extremely scalable setup monitoring and serving thousands of active VMs Implementing user / admin management part, administration console, billing system, trouble ticketing and auto-verification daemon.
– Design and implementation of many UI parts of the app, both on server and front-end side.
Leveraging angular, web-sockets, CDN, back-end workers
– Fully automated infrastructure deployment (web servers, load-balancing, db servers) through
Ansible and code deployment through Capistrano
– Building automatic, concurrent, daemon-based system for pro-active system verification and
anomaly detection. Leveraging actor model, sidekiq workers, common db, threads supervising
– Consolidating 3rd party services through the API. Examples: stripe, paypal, zendesk, mapbox,
sift-science, AWS s3, pingdom
– Designing and implementing REST API interface. Integrating Grape with Rails. Token based
authentication combined with adaptive calls throttling. Automated API documentation based
on Swagger

Senior RoR/JS Developer – FancyGiving.com January 2014-January 2015

-Lead full stack developer of this SOA oriented social system for group wishing/buying.
-Serving over100 000 users.
-Implementation of highly reusable code with leverage of software patterns and OO principles. Over 30 000 lines of code.
– Improved the speed of the system by HTTP, fragment, query, russian-doll caching. HTML
redesign for better performance.
-Speed up front-end techniques: lazy loading, pre-cache, single page application. Speed up data access by rewriting SQL queries, better indexing and slow queries analysis. Postgres stored procedures, triggers, server programming
– Multi-threading concurrency by using native threads, futures, actors for better performance
using both MRI Ruby and JRuby. Highly increasing concurrency and resource usage by
proper server’s process and threads handling. Leveraging Puma and Unicorn rack servers
– Leveraging Rails/Rack middleware system for better composition of software layers. Handling
authorization, caching, redirecting, CORS, etc. as Rack middleware services.
– Improved internal SEO characteristics by generating automatic description inside the tags,
using proper naming for external resources, leveraging meta tags, facebook graph tags and
microdata structures.
– Building dependent and independent SOA services. Examples: fuzzy logic service for finding
best product based on JRuby and AWS SQS service, communication service for external systems, data analytics system.

RoR/JS Developer – Relaximo.pl January 2010-December 2013

-Lead full stack developer for highly scalable, multi-application, multi-threaded distributed system.
-Demonstrating proper skills to design and implement very complex eco-system of mutually dependent applications and data base systems. Over 40 000 lines of code.
– Implementation of highly sophisticated rental system. Complex model, able to manage daily/
hourly rental, serving seasons, tariffs, multi-assets and many pricing models (per season/tariff)
– Implementing communication (facebook style) system with public/private streams. Able to
handle many different stream objects, serving as notification API server with ability for private
messaging. Server is designed as communication portal for multi-user social network system.
– Implementation of collaboration system for handling social plans and multi-user project
-Building voting system, internal communication, notes, tasks management,
internal and external user invitations
– Implementation of internal search engine for handling day-by-day availability, pricing and
geographic distance queries
– Implementation of highly interactive front-end environments for SPA pages. Leveraging
Backbone.js, backbone-relational, jQuery-data model, jQuery-ui, RESTfull API communication.

Channel Manager – Intermec March 2009- December 2009

-Managed channel of technology partners to support business development in Poland.
-Actively finding new partners with proper technical and application development skills.
– Secured engagement with 30+ new Tier 2 and Tier 1 partners in the region and provided training on products, software and services
– Set-up the local, centralized service center for Poland.

Technical Manager – Motorola / Symbol Technologies September 2004-March 2009

-Leading team of 12 technical people.
-Serve as a driving force in developing business and relationships for this global manufacturer of enterprise mobility products (e.g., rugged mobile computers, wireless infrastructure equipment, radio frequency identification equipment, mobility management system, bar code scanners).
– Secured engagement with 50+ new Tier 2 and Tier 1 partners in the region and provided training on products, software and services
– Organized technical trainings for team members
– Team was honored with the Team Achievement Award, which was announced at the worldwide
conference in Texas.

Project Manager – Marconi Communications March 1999-July 2004

-Joined a multi-regional designer, manufacturer, and supplier of telecommunications and information technology equipment and services enabling customers to evolve narrowband networks to next generation broadband networks (company was acquired by Ericcson).
– Completing installation on two sites that had been negotiated by predecessor to be excluded from the contract because of implementation difficulties;.
– Presented solutions at telecommunication fairs, which started the sales process with two new
clients extremely interested in the company’s solutions.

Area Manager, Radio Division– Sirti March 1998-February 1999

-Rapidly promoted in 10 months from position as a designer of telecommunications networks to a
management role with this leading international €700 million company engineering telecommunication networks and systems.
– Managed the full lifecycle planning and completion of a USD $15 million project for the
installation of radio-based telephony in eight cities covering 15,000 subscribers.

Embedded System Developer – Nokia Communications January 1996-June 1997

-Selected as a team member of the Video Lab in the Research Center of this USD $41 billion
international manufacturer of telecommunications equipment.
-Managed the entire project lifecycle for the preparation of communication software for video equipment, including collaboration with software partners.
– Completed the sub-project within an aggressive deadline schedule of six months.
– Prepared device driver in C++ for Windows based systems.
– Recommended encapsulating IP traffic in MPEG stream, which was later implemented in the
production software.

Education history

Franco-Polish School of New Information & Communication Technologies 2006-2008 Master of Science – Computer & Telecommunication Engineering
Master of Science, Economics – Management & Marketing Studies
Institute Nationale des Telecommunication 1998-2000 Institute Nationale des Telecommunication – Evry-Paris, France
Major – Data Networks
Silesian Technical University 1994-1998 Silesian Technical University, Poland
Major – Computer Science
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