Jacek Mariański
Fullstack Developer & AI Enthusiast
10+ years building software across enterprises, startups, and indie projects. From enterprise .NET and Java systems to AI-powered tools and rapid prototyping. Currently exploring the intersection of LLMs, automation, and developer experience.
Core Skills
Tech stack I work with regularly
Languages & Frameworks
Frontend
Backend & Tools
DevOps & Data
AI & Emerging Tech
- →AI Agents & Autonomous Systems - Building tools that think and act independently
- →Claude Code & AI-Assisted Development - Pushing the boundaries of AI-powered coding workflows
- →Rapid Prototyping & Indie Hacking - From idea to working product in days, not months
- →Multi-agent Systems - Coordinating multiple AI models for complex tasks
Highlighted Projects
Key projects that showcase different aspects of my work
Contributed to a major European logistics portal during a critical team transition. Led Next.js 12→14 migration, visual redesign, and expanded to 3 new markets (ES, IT, FR) via the PolyTrans plugin.
Microservices architecture for AI-powered subtitle generation. Coordinated freelancers and AI models to produce high-quality subtitles for TV series at scale.
Upgraded Confluence plugin to version 2.0, optimized for Data Center deployment. Improved performance and scalability for enterprise use.
Led complete rebuild of e-commerce platform from legacy codebase to modern framework. Integrated multiple internal systems and maintained warranty period.
Experience Timeline
Journey through different tech stacks and industries
Building AI-powered tools and exploring the intersection of LLMs, automation, and developer experience. Focus on rapid prototyping, indie hacking, and pushing boundaries of what's possible with modern AI.
Joined during a critical team transition, ensuring project continuity for trans.info — a major European logistics portal. Assisted with Next.js 12→14 migration, led visual redesign, expanded the platform to 3 new markets (ES, IT, FR) via the PolyTrans plugin, and improved analytics and ad monetization. Deepened the business relationship with Trans.eu. Currently continuing to work with Trans.eu on their WordPress properties and other technology initiatives.
Enterprise development and client projects across diverse tech stacks. Built microservices, CMS plugins, and e-commerce solutions for international brands and agencies.
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Growth phase working on diverse projects from e-commerce platforms to real-time streaming tools. Led technical implementations and client relationships.
First professional role building internal tools for Norwegian accounting platform. Worked on reporting systems within the etoll.no product family.
Specialization: Internet & Mobile Technologies
I'm open to freelance projects, contract work, and interesting technical challenges. Whether it's modernizing legacy systems, building AI-powered tools, or architecting new platforms.