I’m a pragmatic, empathetic software engineer who loves programming and helping clients solve technical challenges. As founder and CTO of DG Spectrum, I lead the building of web and mobile applications, architect scalable systems, and guide development teams to deliver high-quality software. I enjoy mentoring teams, improving technical skills, and driving modernization efforts across frontend and backend. My toolkit includes TypeScript, React, Vue, Nuxt, Next.js, Nest.js, Docker, Kubernetes, NGINX, and cloud platforms like AWS and Azure. I focus on API integrations, performance optimization, and CI/CD, while exploring AI/LM tools for new solutions. I also manage partnerships and contracts in the public sector, energy, and startup ecosystems.

Jacek Leszczynski

I’m a pragmatic, empathetic software engineer who loves programming and helping clients solve technical challenges. As founder and CTO of DG Spectrum, I lead the building of web and mobile applications, architect scalable systems, and guide development teams to deliver high-quality software. I enjoy mentoring teams, improving technical skills, and driving modernization efforts across frontend and backend. My toolkit includes TypeScript, React, Vue, Nuxt, Next.js, Nest.js, Docker, Kubernetes, NGINX, and cloud platforms like AWS and Azure. I focus on API integrations, performance optimization, and CI/CD, while exploring AI/LM tools for new solutions. I also manage partnerships and contracts in the public sector, energy, and startup ecosystems.

Available to hire

I’m a pragmatic, empathetic software engineer who loves programming and helping clients solve technical challenges. As founder and CTO of DG Spectrum, I lead the building of web and mobile applications, architect scalable systems, and guide development teams to deliver high-quality software.

I enjoy mentoring teams, improving technical skills, and driving modernization efforts across frontend and backend. My toolkit includes TypeScript, React, Vue, Nuxt, Next.js, Nest.js, Docker, Kubernetes, NGINX, and cloud platforms like AWS and Azure. I focus on API integrations, performance optimization, and CI/CD, while exploring AI/LM tools for new solutions. I also manage partnerships and contracts in the public sector, energy, and startup ecosystems.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
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Language

English
Fluent
German
Intermediate

Work Experience

Founder and CTO at DG Spectrum
July 1, 2023 - Present
Founded and leads DG Spectrum; builds web and mobile applications; architects scalable systems; oversees development teams; containerization and cloud optimization; APIs and integration; work with public sector and AI/LM tooling.
Front-End Developer at Ekofachowcy.pl
June 1, 2022 - September 22, 2025
Front-end development using React/TypeScript; implemented custom layouts and WordPress/ACF integrations.
Full Stack Developer at Moto-zone
February 1, 2022 - September 22, 2025
Developed full-stack features; created moto-zone.org and custom components; self-hosted apps; integrated with Allegro REST API; worked with React.js, TypeScript and Figma-driven tasks.

Education

at University of Gdansk
January 1, 2020 - September 22, 2025
at Capgemini
July 1, 2022 - July 1, 2023

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Professional Services, Government, Media & Entertainment, Education