Matej Vrzala
Product-focused software engineer with 9+ years of experience building data-intensive applications, developer tools, and user-facing products. Strong background in data visualization, full-stack development, and research-driven environments. Proven ability to improve performance, design systems, and support complex analytical workflows.
Professional Experience
Hash AI — Remote
Short-Term Contract (2026)
- Developed a prototype for spec-driven development as part of the ARIA Safeguarded AI program.
- Stack: React, Express, DoltDB, Claude Agentic SDK, OpenCode SDK.
Epoch AI — Remote
Staff Developer & Contract (2025)
- Built a reusable data visualization framework on top of D3.
- Developed a UI component system using Web Components to standardize website design.
- Conducted technical analysis of projects proposed to leading AI labs.
- Collaborated closely with researchers to translate complex data into usable interfaces.
- Developed a leading AI math benchmark and agentic tool.
Metaculus — Remote
Platform Developer (2019 – 2024)
- Developed a leading community-driven, reputation-based forecasting platform.
- Helped scale the company from a 2-person team to a 20+ FTE organization.
- Built and maintained full-stack features using Django, React, Angular, D3, and PostgreSQL.
- Guided architectural decisions influencing the platform's scalability and long-term maintainability.
- Developed interactive data visualizations to support probabilistic forecasting and user insights.
Nano Energies — Prague
Internal Product Developer (2019)
- Developed internal management systems for an energy company as part of a core backend team.
- Transitioned into leading frontend development, significantly improving usability and system accessibility.
- Delivered end-to-end features bridging backend logic with user-facing interfaces.
CyberFox — Prague
Software Developer (2018)
- Optimized large-scale database queries, improving search performance by 3–5x (up to 10x in edge cases).
- Designed and implemented integration between WooCommerce and warehouse systems.
- Maintained and optimized data-heavy systems requiring high performance and reliability.
Grün — Bratislava
Software Developer (2017)
- Refactored a legacy codebase and modernized the architecture of NGO management software.
- Built a full donation payment system, enabling online fundraising for multiple organizations.
- Delivered end-to-end product features with direct real-world impact.
Technical Skills
- Main Stack: Python (Django, FastAPI), TypeScript (React, Next.js, Vue, Angular, D3, Bun, NodeJS), PHP (Symfony, Yii2, Zend), SQL
- Additional Tools & Languages: C++, Rust, Go, Zig, Lua
Additional Projects & Interests
- Led the development of a custom 3D game engine and lightweight IDE in C++ and OpenGL.
- Built experimental products and full-stack applications, including one reaching thousands of users across multiple countries.
- Passionate about developer tools, data systems, and interactive visualization.
Additional Experience & Education
- Active member of the Effective Altruism community (organized events, discussions, and retreats).
- Recommended and mentored 10+ individuals who successfully transitioned into new tech roles.
- Winner — Škoda Warehouse Hackathon.
- Completed courses from institutions including Oxford and MIT; studied Electrical Engineering.
- Graduated from a Colorado-based relational leadership 2-year program.
Languages
- Slovak: Native
- Czech: Fluent
- English: C1
- German: A2
- Spanish: A1