Full Stack Developer with strong backend ownership experience, skilled in designing and deploying scalable Node.js/TypeScript services. Practitioner of clean code, modular architecture, and maintainable systems. Collaborative team player with a background in project management from IBM and khora.berlin, bringing structure and a delivery mindset to development work.

Jacek Roszkowiak

Full Stack Developer with strong backend ownership experience, skilled in designing and deploying scalable Node.js/TypeScript services. Practitioner of clean code, modular architecture, and maintainable systems. Collaborative team player with a background in project management from IBM and khora.berlin, bringing structure and a delivery mindset to development work.

Available to hire

Full Stack Developer with strong backend ownership experience, skilled in designing and deploying scalable Node.js/TypeScript services. Practitioner of clean code, modular architecture, and maintainable systems. Collaborative team player with a background in project management from IBM and khora.berlin, bringing structure and a delivery mindset to development work.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
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Language

Polish
Fluent
English
Advanced
German
Intermediate

Work Experience

Full Stack Developer at Wandar
January 1, 2025 - Present
Solely responsible for backend development using Node.js, TypeScript, PrismaORM, PostgreSQL, and Supabase. Developed unit and integration tests with Jest to ensure backend reliability. Applied version control best practices using Git for collaboration and traceability. Ensured backend documentation adherence to OpenAPI standards. Designed and optimized scalable, efficient, and maintainable backend architecture. Developed and maintained frontend features in React.js, focusing on performance optimization and codebase refactoring. Designed robust PostgreSQL data models for high performance and seamless integration. Selected and integrated ORM tools to streamline and optimize database workflows. Established scalable, modular project structure using Node.js and TypeScript.
Professional Development - Career Break at Berlin
December 31, 2024 - August 21, 2025
Dedicated time to skill advancement through structured learning. Completed a Full Stack Programming course at ReDI to refresh and deepen software development capabilities, followed by AWS Cloud Computing Certification at Neuefische to broaden infrastructure knowledge. Engaged actively with the tech community by connecting with professionals across disciplines, participating in industry events, meetups, and volunteering in initiatives aligned with personal values. Focused on mental clarity, discipline, and self-directed growth to support long-term professional resilience. Gained cross-cultural insights and adaptability through international travel—skills critical to functioning in diverse, distributed teams.
Web Developer and DevOps Engineer at Mowea GmbH
December 31, 2023 - August 21, 2025
Built a dashboard prototype in React.js for real-time turbine data visualization and statistical analysis. Maintained and extended MOWEA’s public website using Vanilla JavaScript, ensuring functional integrity and responsiveness. Developed a Digital Product Nameplate using Vanilla JavaScript for product identification and metadata access. Administered backup and recovery systems to ensure data resilience and minimize loss during failure. Installed and configured system software, updates, and security patches to maintain infrastructure integrity. Performed hardware diagnostics and software testing to validate operational stability. Conducted routine system maintenance and performance monitoring to ensure optimal uptime. Managed user account administration, permissions, and access controls in a Windows Server environment. Delivered technical support to end-users, troubleshooting system issues and resolving server-related incidents.
Junior Software Developer at IOTA Foundation
October 31, 2022 - August 21, 2025
Delivered operational microservices for the EU-funded CityXchange project, enabling six cities to adopt smart energy solutions using IOTA Distributed Ledger Technology (DLT). Contributed to scalable component development using React.js, Svelte, Node.js, Nest.js, TypeScript, and MongoDB across both front-end and back-end layers. Supported system integration by connecting client-side interfaces with backend logic for end-to-end functionality. Applied software engineering best practices, aligning development with standards from other open-source DLT initiatives. Implemented service monitoring using Prometheus and Grafana to ensure system observability and operational transparency. Wrote comprehensive unit and end-to-end tests using Jest and Supertest to verify system robustness. Authored technical documentation adhering to OpenAPI standards, using Swagger for APIs and Draw.io for architecture visualization.
Project Manager/Business Owner/Startup Collaborator at khora.berlin / self-employed
October 31, 2021 - August 21, 2025
Co-founded khora.berlin, Berlin’s first independent food delivery service, contributing to its concept, development, launch, and operational scaling. Founded and operated a Berlin-based logistics business, managing all end-to-end operations. Led full-cycle project delivery across logistics and entertainment sectors, from initiation to closure, ensuring alignment with client objectives. Directed remote, cross-functional teams, assuring clear task ownership and on-time execution. Maintained clear client communication through regular updates on project status and deliverables.
IT Project Manager at IBM
April 30, 2015 - August 21, 2025
Delivered network and telecommunication infrastructure projects across six remote sites in Europe and the UK. Led a UK-wide infrastructure clean-up initiative, achieving £1M in annual cost savings. Managed server room and office infrastructure roll-outs and transitions for facilities hosting hundreds of workstations, ensuring service continuity and minimal disruption during relocations. Directed remote project teams and facilitated regular stakeholder meetings to ensure alignment and progress visibility. Produced project documentation including Project Plan, Communication Plan, and Risk & Issue Management. Assessed project risks and created risk mitigation plans.
Project Management Officer (PMO) at IBM
September 30, 2013 - August 21, 2025
Worked alongside the Project Manager in pilot project delivery. Assisted in project planning and creating project documentation. Tracked project progress against the Project Plan. Facilitated resource allocation through continuous asset monitoring. Planned project meetings and managed communication following the Communication Plan. Managed project documentation.
IT Projects Coordinator at IBM
January 31, 2012 - August 21, 2025
Coordinated team communication by planning and hosting project status calls, ensuring meeting minutes. Tracked and controlled projects by providing status reports and optimizing tasks. Reviewed project documentation, ensured process compliance, and handled all team administrative duties.
Sales Representative and IT Consultant at OGICOM
April 30, 2011 - August 21, 2025
Focused on Small and Medium Business clients, drove new customer acquisition, and maintained strong relationships with existing clients. Analyzed client requirements and leveraged product expertise to deliver tailored IT solutions for e-commerce and web presence, aligned with business objectives. Delivered exceptional customer support, ensuring high levels of satisfaction and long-term client retention.

Education

Master of Arts: Sociology - Market Research and Communication at University of Wrocław
October 1, 2003 - September 30, 2009
Full Stack Web Development Bootcamp at SPICED Academy
November 1, 2020 - January 31, 2021
MERN Stack Bootcamp at ReDI School of Digital Integration
October 1, 2023 - March 31, 2024
AWS re/Start Cloud Computing Bootcamp at Neuefische, Hamburg
September 1, 2024 - December 31, 2024

Qualifications

AWS Cloud Practitioner
December 1, 2024 - August 21, 2025
Full Stack Web Development Bootcamp
March 1, 2024 - August 21, 2025
Agile WoW Workshop
December 1, 2023 - August 21, 2025
MERN Stack Web Developer Certification
January 1, 2021 - August 21, 2025
Leadership and Team Building
July 1, 2013 - August 21, 2025

Industry Experience

Software & Internet, Professional Services, Energy & Utilities, Transportation & Logistics, Telecommunications

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
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