Jan Tovornik
JAN
TOVORNIK

Jan Tovornik

Integration Engineer - APIs, ETL, data pipelines

Ptuj, Slovenia 🇸🇮

$ about

Backend software engineer with 7 years of experience developing and maintaining third-party API integrations, transforming external data into business-critical systems, and troubleshooting production issues. Experienced with REST APIs, OAuth, ETL workflows, .NET, TypeScript, PostgreSQL, Docker, and Git. Passionate about improving software engineering skills through personal projects and modern backend development.

View CV

$ work_experience

Fullstack Developer

Dec 2025 -

Tenzor | Ptuj, Slovenia

  • Developing internal .NET services integrating surveillance hardware with business applications.
  • Designing REST endpoints and implementing business logic.
  • Working across backend and UI features for internal operational tools.

C# .NET MSSQL HTML, CSS, JS

Integrations Engineer

Oct 2019 - Oct 2025

Databox | Ptuj, Slovenia

  • Built and maintained 100+ third-party REST API integrations across multiple vendors.
  • Implemented authentication flows, pagination, data mapping, and transformation logic for external APIs.
  • Diagnosed and resolved production data discrepancies by tracing issues across external APIs, transformation pipelines, and internal systems.
  • Collaborated closely with platform engineers responsible for shared API infrastructure and integration tooling.
  • Authored internal documentation and onboarding guides for new integration developers.
  • Adopted AI coding tools throughout the role - starting with GitHub Copilot in the early days, moving to Cursor, and most recently Claude Code - integrating them into daily development to ship faster and explore new problem-solving approaches.

PHP TypeScript Node.js PostgreSQL REST APIs AI

Full-stack developer

May 2018 - Sep 2019

Faculty of Electrical Engineering and Computer Science | Maribor, Slovenia

  • Worked as a Full-Stack Developer at IGEA d.o.o., contributing to the development and management of Serbia's Geographic Information Systems (GIS).

Java HTML & CSS JavaScript Oracle SQL GIS

Android developer

Aug 2017 - Jul 2018

Ad Systems | Marezige, Slovenia

  • Developed an Android application that overlays ads on top of the display, primarily designed for TV use.

Java Android

$ personal_projects

Horse Riding Club Management App

Apr 2025 -

Developing an app to help horse club owners manage their clubs more easily.

React NestJS PostgreSQL AI

Event Management App

Mar 2025 - Mar 2026

Developed a mobile app to organize and manage recurring events, particularly for sports clubs, streamlining the scheduling of daily and weekly activities such as practices and matches.

Android Kotlin Firebase AI

Inventory Synchronization System

Jan 2024 - Oct 2025

Helped develop the backend part of an application synchronizing inventory across multiple e-commerce platforms with conflict resolution and centralized stock management.

TypeScript PostgreSQL REST APIs

Car Trip Logger

Apr 2023 - Mar 2025

Developed an Android app to track car trips and a web app to monitor them and generate reports based on recorded data.

Java Android React Firebase

Web scraping

Jan 2021 - Jan 2023

Developed an automated system to monitor and track new entries, price changes, and deals on items such as smartphones and real estate. Primarily used for personal projects, with additional applications delivered to clients on Fiverr.

Python MongoDB

$ education

Master's degree in Computer Science

2017 - 2020

Faculty of Electrical Engineering and Computer Science | Maribor, Slovenia

Bachelor's degree in Computer Science

2014 - 2017

Faculty of Electrical Engineering and Computer Science | Maribor, Slovenia

High School Graduate - Computer Science

2010 - 2014

School of Electrical Engineering and Computing | Ptuj, Slovenia

$ skills

Languages

TypeScript PHP C#

Backend

Node.js PostgreSQL REST APIs .NET RabbitMQ Redis

Tools

Postman Sentry Git AI Kibana Docker Grafana

$ languages

Slovene Native

English

Listening C1 - Proficient User
Reading C1 - Proficient User
Spoken interaction B2 - Independent User
Spoken production B1 - Independent User
Writing B2 - Independent User