Master's degree
Zagreb University of Applied Sciences
2021 - 2023
Engineering in Information Technologies
Filip Vasiljević
Software Architect / Full-Stack Engineer Master's Degree
Zagreb, Croatia +385 91 931 0730 developer@feyton.net
About
Software Architect and Full-Stack Engineer with a Master's degree and years of experience delivering production enterprise web applications, specializing in high-concurrency distributed .NET and React systems.
Programming languages
Core: C#, TypeScript, JavaScript
Additional: C, C++, Rust, Python, PHP
Frameworks, libraries & technology
Core: .NET, React
Additional: NestJS, Node.js, Vue
Libraries: Kendo, Material UI, Shadcn, CSS Modules, Redux, Context, MobX, Pinia
Data, platforms & tools
Databases: Microsoft SQL Server, PostgreSQL, SQLite, MongoDB
LLMs: LM Studio, Ollama OS: Ubuntu, macOS, Windows Misc: Tauri, CapacitorJS
Education
Bachelor's degree
Zagreb University of Applied Sciences
2018 - 2021
Computer and Information Sciences
High school
Technical School Ruđer Bošković
2014 - 2018
Computer technician
Languages: Croatian (Native), English (Fluent)
Driving license: B
Work Experience
Software Architect, Full-Stack Engineer
Adnet - Končar Group, Zagreb
02.2022 - Ongoing
React, Vue, TypeScript, C#, .NET, NestJS, SQL, Git
- Technological decision maker for a large 5+ year greenfield project that fully digitalized key workflows for the Croatian Railways operator (HŽ Infrastruktura) and other high-profile clients.
- Worked on several large government web applications for the Independent TSO in Croatia and the Croatian Railways operator (HŽ Infrastruktura).
- Developed and maintained an in-house component library using Storybook, React, Vue, and TypeScript across multiple projects; tested with K6 and Playwright.
- Mentored other developers.
Software Engineer
Omega Software, Zagreb
04.2018 - 10.2018
C#, .NET, SQL, Git
- Developed and maintained several established production applications.
Work Projects
Route Ordering Software, Croatian Railways Operator (HŽ Infrastruktura)
Software Architect, Full-Stack Developer, Lead Maintainer
Croatian Railways Operator (HŽ Infrastruktura) - Digital Workflow Application
- Developed, delivered, and maintained a high-concurrency distributed production system.
- Played a key role in architecture planning and implementation on a team of 7+ developers.
- Worked across a broad, interconnected network of failover APIs and proxies underpinning a highly available distributed system.
- Implemented two-factor authentication.
- Implemented lazy-loaded authentication guards.
- Implemented role-based authorization walls.
- Monitored and optimized performance for high-concurrency scenarios.
- Implemented hot-path caching.
- Contributed to backend development using .NET (C#), Microsoft SQL Server, and Node.js, focusing on performance optimization and system stability.
- Implemented custom frontend functional components in React.
Market Applications, Croatian TSO
Full-Stack Developer
Croatian TSO - Market Management System
- Developed and maintained a web-based Market Management System for ENTSO-E scheduling, capacity management, reserve resource tracking, and settlement processes, continuously enhanced under an agile framework contract.
- Developed multiple frontends in React, Vue, and TypeScript using microfrontend and submodule architectures, and maintained shared component libraries with Storybook and Figma.
- Contributed to backend services in .NET Core and Node.js, powered by Microsoft SQL Server and PostgreSQL, and deployed on IIS.
Personal Projects
Personal Project
Worker Shift Management App
Solo Full-Stack Developer
- Built a worker-facing app for viewing and managing shifts.
- Built an employer-facing scheduling app for planning and assigning shifts.
- Implemented a hybrid login: an employee account can unlock partial employer functionality through a manager mode.
- Implemented Kanban-board-based shift planning.
- Built a calendar system for tracking per-location events (e.g., parties) on specific dates to inform shift staffing.
- Implemented shift request and handover logic for trading and reassigning shifts between workers.
- Built vacation planning and approval workflows.
- Implemented shift absence tracking.
- Built shift statistics dashboards with Chart.js.
Personal Project
Local LLM Code-Auditing Tool
Solo Full-Stack Developer
- An auditing tool for detecting code missteps and faults, powered by large language models running entirely locally on my machine.
- Runs fully contained on my own system, no code or data ever leaves it.
- Swappable local models (Gemma, Qwen, and others) served through LM Studio and Ollama.
- I use the tools I make: I built this one for myself, to make sure everything I ship is bulletproof.
Personal Project
AI Content Farm
Solo Full-Stack Developer
- Automated a full short-form content pipeline: one button press produces a finished TikTok / Instagram Reels / YouTube Short, start to finish, for Paragon, a daily Bible app I built.
- Used Google Gemma and Qwen, served locally through LM Studio and Ollama, to generate a 90-second script in which the AI reads a Bible passage and reflects on it.
- Drove a Puppeteer-controlled headless Chrome instance to record the app as if a real user were reading and interacting with it.
- Converted the generated script into a natural voiceover with ElevenLabs.
- Merged the screen recording, voiceover, and script into the final video using FFmpeg.
Personal Project · Published on Google Play
Paragon: Bible and Prayer Tool
Solo Full-Stack Developer
- Built and published a daily Bible and prayer app for Android, live on Google Play.
- Implemented offline reading of all 66 books of the Bible with keyword search across the full text.
- Built color-coded verse bookmarking, a bookmarked-verses list, and a prayer-reflection journal.
- Implemented a prayer timer that tracks time spent in prayer alongside optional written reflections.
- Built a home-screen widget that surfaces a Bible verse on a set schedule, plus configurable push notifications (twice-daily, daily, or weekly) for verse reminders.
- Implemented full dark mode support.
Google Play: play.google.com/store/apps/details?id=net.feyton.bible_tool
Volunteer and Hobby Projects
Volunteering
Charity Developer - Zagreb University of Applied Sciences
Led a volunteer team of student developers in the creation of a custom Content Management System for Croatian elementary schools.
RevenueCat One-Month Hackathon
Tinder for Nomads
- Built a swipe-based matching system.
- Built a beacon-on-Leaflet matching system.
- Implemented chat and group chat with socket integration.
- Deployed the application to an Ubuntu VPS.
- Integrated RevenueCat payment processing.
- Implemented custom login with Google and Apple sign-in support.
One-Month Game Jam
4X Civilization-Like Game Prototype
- Implemented Perlin-noise terrain, biome, and elevation generation in C#.
- Implemented pathfinding on a 2D hexagonal-tile matrix.
- Built world wrapping for infinite horizontal camera movement.
- Created a SQLite database of randomly generated humans and a DNA system.
- Implemented 2.5D graphics.
- Built a settlement expansion system covering development, food stockpiles, residents, governor selection, and overlapping border graphics.