Lead Software Developer · Production AI systems, agentic workflows, and infrastructure
I design, ship, and operate systems that embed LLMs and tool-calling agents into real business processes.
Focus: low-latency conversational agents, speech pipelines, background orchestration, and production-grade FastAPI + Next.js stacks that stay reliable under real traffic.
Agentic & LLM systems
- Voice + text business assistant with tool calling (OpenAI + OpenRouter + Grok LLM), real-time WebSockets, speech-to-text (including Grok STT), and background workers (invoices, quotations, partners, fiscalization).
- Multi-model routing via OpenRouter for cost/latency control and model fallback.
- VOD analysis pipeline (STT → keyword detection → timestamped clips → automated coaching reports).
- OpenWA booking agent that turns chat messages into confirmed reservations + HUB3 payment tracking.
- Context management, safe tool execution, retry/logging, and observability as first-class concerns.
Platform & infrastructure
- FastAPI / NestJS backends, PostgreSQL, Redis, WebSockets, background task queues.
- Next.js frontends + Android-wrapped clients.
- Full deployment ownership: Hetzner + Railway, Linux, Nginx, DNS, SSL/TLS, firewalls, monitoring, backups, recovery procedures.
- Multi-tenant data separation, high-volume invoice/request handling, and secure external integrations (Croatian Fiscalization 1.0/2.0, XML/SOAP, FINA).
| System | Role | Stack / Notes |
|---|---|---|
| pasko.hr | Voice-enabled business assistant for Croatian SMEs | FastAPI · Next.js · OpenAI + OpenRouter + Grok LLM · Grok STT · tool calling · PostgreSQL · Redis · WebSockets · Fiscalization |
| app.pango-coach.app | AI coaching platform for VALORANT teams | FastAPI · NestJS · Next.js · STT · Discord bot · VOD analysis · playbooks |
| bkalpha.hr | Digital membership card + stats + activation | FastAPI · Next.js · Android-wrapped client |
| app.udruga-carpus-dei.hr | Workshop/therapy booking + HUB3 payments | FastAPI · Next.js · OpenWA agent |
| logicna-podloga.hr | 20 production Astro static sites for businesses | Astro · performance & SEO focused |
Python · FastAPI · TypeScript · NestJS · Next.js · React
PostgreSQL · Redis · WebSockets · Docker
OpenAI APIs · OpenRouter · Grok LLM · Grok STT · speech-to-text · tool calling · agent orchestration
XML / SOAP · Fiscalization · Discord API · OpenWA
Nginx · Linux · DNS · SSL/TLS · Hetzner · Railway