Tomislav Ćalušić — software engineer

I build the unglamorous parts of AI products.

Full-stack engineer, nine years across banking, telco, automotive, and government enterprise. Lately I've been wiring Claude into real products — agentic tool-use loops, multi-tenant infra, the boring auth / storage / DNS plumbing that lets a model-powered feature ship to actual users.

Experience

9yrs

Roles

Side projects

4live

Languages

Selected projects

Live in production.

Four side projects — two AI builds, a Croatian full-stack platform, and a Web3 hosting dApp.

OpenAI GPT embeddings + pgvector .NET 10 multi-tenant live co-built

Adios — adios.hr

A production AI-powered news platform. Ingests RSS feeds from major publishers, then runs every article through a structured LLM analysis: editorial summary, normalised title, topic and named-entity tags, and four perceptual scores including clickbait detection, vagueness, typo, and emotional-language signals.

Cross-source clustering blends four text-embedding vectors per article with text similarity and tag overlap to group different outlets' coverage of the same story. Multi-tenant by deployment: adding a new country takes a config file plus translations — no code changes to the AI pipeline. Co-built with a colleague; live at adios.hr.

Photo Portfolio Platform

The bot isn't a chat-UI on top of a CMS — it is the CMS. Every operation a photographer might want — uploading a photo, setting a caption, binding a custom domain — exists as a tool the model can call. No admin panel by design.

The interesting bits sit in the infra: raw SQL over an ORM so tenant filters stay loud, Caddy on-demand TLS gated by a registration-check endpoint, and a DNS flow that walks non-technical users through an A record in plain Croatian.

Veseljko — veseljko.hr

An end-to-end Croatian platform for the full lifecycle of weddings, baptisms, birthdays, and other family events. Event owners get digital invitations with RSVP, guest photo and video uploads, printable invitations and QR cards, seating arrangements, package and add-on commerce, and a back-office admin app — all under one roof.

The interesting bits sit in the architecture and the templating: clean-architecture .NET 10 with custom CQRS abstractions, a themed-invitation engine driving 30+ database-seeded themes per event type with CSS-only theming and a placeholder substitution pipeline, plus a browser-native print pipeline verified end-to-end with headless Chromium PDF rendering.

DeHost — dehost.io

A decentralized hosting platform that publishes websites and files fully on-chain — no traditional servers, no takedowns, no single point of failure. Users register blockchain domains, connect their wallet, and publish content directly through the app.

Co-built with a colleague as a SvelteKit + TypeScript dApp on the Base chain. The frontend surface covers wallet onboarding with modern account-abstraction sign-in, on-chain domain registration and management, and the file-publishing flow, on top of a reusable Svelte 5 component library. Currently live on Base testnet at dehost.io.

Back-end & data

Multi-tenant Postgres, SQL-first APIs, integration glue, regulated/financial workflows.

Java · Spring Boot · Python (FastAPI) · Oracle PL/SQL · Postgres

Front-end

Angular and React SPAs replacing legacy back-office UIs, Next.js, TypeScript-first.

Angular · React · TypeScript · Next.js · Svelte · SvelteKit · Vue.js

AI / LLM integration

Agentic tool-use loops, evals, the boring auth/storage/DNS plumbing that lets a model ship.

Claude (Haiku, Sonnet, Opus) · OpenAI · tool-use loops · evals

Infra & delivery

Docker, Caddy with on-demand TLS, Cloudflare R2, Jenkins CI/CD, raw Linux.

Docker · Caddy · Cloudflare · Jenkins · Linux

Nine years, six roles.

Most recent role expanded; older roles condensed. Full details on the CV.

Senior Software Engineer · Intellexi

Oct 2024 — Present

Lead developer on front-office modernization at HPB — Croatian Postal Bank.

Architected and shipped a new Angular SPA replacing a JSF legacy used daily by bank personnel. Designed the Spring Boot REST APIs and a gateway/routing layer connecting front-end to core financial back-ends.

Built real-time HROK integration for credit-availability checks, dynamic in-code PDF generation for regulated documents (credit agreements, compliance reports, account statements), and 2D barcode scanning for fast document capture and verification in customer-onboarding flows. Owned the Oracle PL/SQL layer, OpenLiberty config, and Jenkins CI/CD pipelines.

Angular · Spring Boot · Java · Oracle PL/SQL · OpenLiberty · Jenkins

Senior Technical Consultant · CloudSense

Sep 2022 — Jul 2024

Salesforce engagements for three telcos — A1, Telefónica, Liquid Telecom.

Shipped A1 Telecom's eCommerce on Salesforce in agile cycles with Apex and Lightning Web Components. Drove a new solution-management process for Telefónica engagements and ran the offline client comms.

Handled BAU bug-fix and feature work for Liquid Telecom (the largest African telecommunications provider) and contributed to Salesforce admin. Code-driven PDF generation via PDF Butler.

Salesforce · Apex · Lightning Web Components · PDF Butler

Details

Software Engineer · GlobalLogic

Jun 2021 — Sep 2022

Two automotive cloud platforms — Stellantis IoV and Daimler / Mercedes Intelligent Cloud.

Stellantis — Internet of Vehicles. Device-management portal in React + TypeScript with Relay/GraphQL, a Java/Spring Boot application gateway behind it, Next.js + Tailwind on the front-end, and Elasticsearch for querying. Jest for front-end tests.

Daimler / Mercedes Intelligent Cloud. Vue.js + TypeScript front-end and Java/Spring Boot back-end with file converters, end-to-end tests in Cypress and JUnit. Multinational corporate environment with a globally distributed team.

React · TypeScript · Vue.js · Java 11 · Spring Boot · GraphQL/Relay · Next.js · Elasticsearch

Details

Software Developer · Maurer Electronics GmbH

Nov 2019 — Jun 2021

Government enterprise platform for tobacco-product traceability.

Helped countries detect illegal smoking products by tracking them from creation to delivery. Three React front-ends — for end users and for the administration team — and Java/Spring Boot REST APIs underneath.

PostgreSQL data layer with optimised SQL queries; unit and integration tests in JUnit; Docker on CentOS 7, Maven, Jenkins.

Java · Spring Boot · React · PostgreSQL · JUnit · Docker · Jenkins

Details

Student Software Developer · Sedam IT

Mar — Oct 2019

Built the back-end for ZgPark — Zagreb's pay-parking-by-phone service.

Designed and developed back-end APIs used by thousands of drivers to buy parking tickets over the phone, plus the admin interface (front + back) used by parking-system operators. MS SQL Server, Tomcat.

Java · XML · MS SQL Server · Tomcat

Details

Student Software Engineer · Ericsson

Mar 2017 — Feb 2019

Two years on the 4G/5G code that carries ~1B mobile subscribers.

Improved and tested cellular network code in an agile team. Optimised legacy C and Java for performance and reduced complexity. Wrote functional and component tests in Erlang and Java (JUnit).

Built a shell-pipeline runner using M4 macros and Bash so test suites ran consistently both locally and on Jenkins.

C · Java · Erlang · Bash · M4 · JUnit · Jenkins

Details

I build the unglamorous parts of AI products.

Live in production.

Adios — adios.hr

Photo Portfolio Platform

Veseljko — veseljko.hr

DeHost — dehost.io

Capabilities.

Back-end & data

Front-end

AI / LLM integration

Infra & delivery

Nine years, six roles.

Let's build something.