Ivan Mijatović

Senior Software Engineer and co-founder of Bookaweb & Infinity

Over the past 15 years, I've built production systems used by thousands of companies and millions of users worldwide, including SaaS platforms, trading infrastructure, and large-scale backend systems.

15+ years experience 20,000+ companies use my software Co-founder
Ivan Mijatovic portrait
TRUSTED BY
Sotheby's International Realty Comtrade Coca-Cola HBC Infinity Bookaweb PropBooster

Selected Work

Selected Work

Three projects I’ve built end-to-end — engineered for reliability, determinism, and scale.

TRADING SYSTEM

Software Architect & Core Engineer · Automated trading system

Polymarket Twin Engine

Deterministic trading infrastructure for prediction markets

Deterministic execution · Backtesting engine · Live trading infrastructure · Event-driven architecture

A trading infrastructure platform built around one architectural constraint: live execution and backtesting must share a single execution path. No environment flags, no conditional branches - the same StrategyRunner, OrderManager, and Portfolio logic processes every event in both modes.

This constraint shaped every design decision. Market data is persisted as raw, ordered events in Parquet so replay can reconstruct exact book state. Strategies are schema-validated and plugin-driven so they remain portable across environments. Fills are latency-aware so backtest results reflect real execution dynamics. The result is a full research-to-production platform, not a trading bot with a backtest mode bolted on.

Impact

  • Achieved full behavioral parity between live and backtest - identical strategy outputs given identical input data.
  • Built a complete event pipeline from raw WebSocket ingestion to structured Parquet storage, enabling reproducible replay at any historical point.
  • Delivered a production system executing automated strategies on Polymarket with end-to-end PnL tracking and settlement.
  • Designed a platform architecture that scales from single-strategy research to multi-bot deployment with isolated per-bot configuration and monitoring.

👤 My Role

  • Architecture - defined the single-pipeline constraint and layered event-driven design that ensures execution determinism across environments.
  • Data infrastructure - built the ingestion pipeline, Parquet storage layer, and replay engine with tick-level order book reconstruction.
  • Execution system - implemented the live trading engine including order management with risk limits, cancel/replace logic, and out-of-order fill handling.
  • Strategy platform - designed the modular framework, plugin system, and schema validation layer for portable, reproducible strategy development.
  • Research tooling - built batch analytics, grid search, and feature export pipelines for systematic strategy evaluation.
  • Operations - created CLI tooling for key management, balance checks, approvals, and multi-bot deployment workflows.
SAAS PLATFORM

Co-founder • SaaS platform • 2018–2023

Infinity

Work Management SaaS platform used by 20,000+ companies worldwide

Multi-tenant SaaS • Scalable backend architecture • Real production workloads

Infinity is a work management platform that helps teams organize projects, workflows, and internal operations.

I co-founded Infinity and designed core backend systems, APIs, and infrastructure supporting production workloads globally.

Impact

  • Used by 20,000+ companies worldwide
  • Built scalable multi-tenant SaaS platform from scratch
  • Powered real production workloads globally

My role

  • Designed backend architecture and APIs
  • Built core platform systems and infrastructure
  • Worked across backend, frontend, and system architecture
TRAVEL MARKETPLACE

Founder • Travel marketplace platform • 2023–present

Bookaweb

Travel marketplace platform integrating hotels, flights, and experiences at scale

Booking orchestration • Availability synchronization • Search infrastructure • Production systems

Bookaweb is a travel marketplace platform integrating millions of hotels, tours, and flight options through large-scale external provider integrations.

I designed and built the core booking infrastructure, including availability synchronization, calendar management, pricing logic, and transactional booking workflows, ensuring consistency and reliability in real production environments.

Impact

  • Integrated millions of travel listings from external providers
  • Built complete booking orchestration system handling availability, pricing, and reservations
  • Designed calendar synchronization and conflict-resolution logic
  • Implemented scalable search and filtering across large datasets
  • Built production systems handling real user bookings and transactions

My role — Founder & core engineer

  • Designed backend architecture and booking system from scratch
  • Built booking workflows, calendar logic, and pricing infrastructure
  • Implemented partner integrations and large-scale data ingestion pipelines
  • Optimized database performance and search indexing
  • Owned production infrastructure and system reliability

Core Technologies

“I build production infrastructure, trading systems, and scalable web services — optimized for reliability and determinism.”

Languages

  • TypeScript
  • JavaScript
  • PHP
  • SQL

Backend & APIs

  • Node.js
  • Laravel
  • REST APIs
  • Webhooks
  • Idempotency
  • Retry & Backoff

Queues & Background Jobs

  • Redis queues
  • Laravel Horizon
  • Workers
  • Scheduling
  • Async pipelines

Data & Storage

  • MySQL
  • Redis
  • Elasticsearch
  • Parquet

Infrastructure

  • Docker
  • Linux
  • Nginx
  • CI/CD
  • WebSockets
  • Event-driven

Trading Systems

  • Market data pipelines
  • Order book reconstruction
  • Execution engine
  • Backtesting engine
  • Deterministic execution
  • Portfolio accounting

AI & Agent Workflows

  • Codex
  • Claude Code
  • MCP
  • OpenClaw
  • ElizaOS
  • Tool-using agents
  • Automation workflows

Blockchain & Web3

  • Solidity
  • Trading bots
  • NFT collections
  • Ordinals
  • Website minters
  • Token launches (TGE)
  • Staking
  • DeFi integrations
  • Ethereum mini-game

Systems Engineering Focus

  • Distributed systems
  • Real-time processing
  • Scalable backend architecture
Available for Engineering Roles and Consulting

Let’s Build Production Systems That Scale

Backend systems, trading platforms, and scalable infrastructure
designed for reliability and long-term growth.

Get in Touch