Tomislav Ćalušić

Software engineer · AI integration · Split, Croatia

Open to AI integration roles

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, and the boring auth, storage and DNS plumbing that lets a model-powered feature ship to actual users.

Email me View CV
Experience
9 years
Roles
6 companies
Shipped
3 products

Selected work · U1–U3

Three products, built and shipped.

One live, one by invitation, one on testnet.

Photo Portfolio Platform

U1 PHOTO

Live, by invitation · v1

A Telegram bot that ships websites.

A multi-tenant SaaS where each photographer runs their own website and domain by chatting with a Telegram bot. The bot is the CMS: every operation, from uploading a photo to binding a custom domain, is a tool Claude Haiku can call.

Role: Solo build · 2026

admin panels, by design
0
from adding the bot to a working site
Minutes
to TLS on a photographer’s own domain
Seconds
of Haiku tokens per tenant a month
A few cents
  • Claude Haiku
  • agentic tool use
  • FastAPI
  • Psycopg 3
  • Alembic
  • Next.js 14
  • +8 more
Case study of Photo Portfolio Platform

Demo on request

The home page of scalusic.photography, a photographer’s site running on the platform: a full-width photo of posts casting striped shadows, a Croatian headline and an EN/HR language switchThe portfolio page of scalusic.photography, a photographer’s site running on the platform, with category filters above a grid of photos
scalusic.photography on a phone, a photographer’s site running on the platform, showing its home page with the language switch and menu
On screen: scalusic.photography, a photographer’s site running on the platform

Veseljko

U2 VESELJKO

Live

Everything a family celebration needs, in one place.

A Croatian platform for the whole lifecycle of weddings, baptisms, birthdays and other family events. It covers digital invitations with RSVP, guest photo and video uploads, printable invitations and QR cards, seating, and package and add-on commerce, with a back-office app for staff.

Role: Co-built with a colleague

event types
8
invitation themes
30+
front ends: Web and Office
2
  • C#
  • .NET 10
  • Clean Architecture
  • CQRS
  • ASP.NET Core MVC
  • Razor
  • +6 more
Case study of VeseljkoVisit veseljko.hr
The veseljko.hr home page in Croatian: the headline “Veseljko: everything your party needs”, a feature list, and phone mock-ups of a wedding’s guest-upload page and RSVP form beside a printed QR cardVeseljko’s package pricing in Croatian: three cards for a free QR gallery starter, digital invitations and a one-month QR gallery, each with a one-off price and its features
veseljko.hr on a phone: the same headline and feature list, with buttons to start a party, try the demo or learn more

DeHost

U3 DEHOST

Live on testnet

Websites that live on-chain.

A Web3 platform that publishes websites and files fully on-chain: no traditional servers, no takedowns, no single point of failure. I built the SvelteKit front end and its Web3 integration: wallet onboarding with account-abstraction sign-in, on-chain domains and publishing.

Role: Co-built: front end and Web3 integration

+ SvelteKit, TypeScript throughout
Svelte 5
injected-wallet sign-in
EIP-1193
account-abstraction sign-in
ERC-4337-style
  • Web3 dApp
  • Svelte 5
  • SvelteKit
  • TypeScript
  • Tailwind CSS
  • Vite
  • +2 more
Case study of DeHostVisit dehost.io
The dehost.io home page: a test-environment warning banner, the “Welcome to DeHost” heading and a card asking the visitor to connect a walletThe “Who is DeHost for?” section of dehost.io, with cards for developers, Web3 teams, communities and DAOs, and creators and activists, above the start of “How It Works”
dehost.io on a phone: the test-environment banner, the welcome heading and the Connect Wallet card

Capabilities · routing table

What I work on, and where it runs.

Capabilities, and which of the projects above use each one
CapabilityU1Photo Portfolio PlatformU2VeseljkoU3DeHost
Back-end & dataMulti-tenant Postgres, SQL-first APIs, integration glue, regulated financial workflows.Java · Spring Boot · .NET · Python (FastAPI) · Oracle PL/SQL · PostgreSQLUsedUsedNot used
Front-endAngular and React SPAs replacing legacy back-office UIs, Next.js, TypeScript-first.Angular · React · TypeScript · Next.js · Svelte · SvelteKit · Vue.jsUsedUsedUsed
AI and LLM integrationAgentic tool-use loops, evals, and the boring auth, storage and DNS plumbing that lets a model ship.Claude (Haiku, Sonnet, Opus) · OpenAI · embeddings + pgvector · tool use · evalsUsedNot usedNot used
Infra and deliveryDocker, Caddy with on-demand TLS, Cloudflare R2, Jenkins CI/CD, raw Linux.Docker · Caddy · Cloudflare · Jenkins · LinuxUsedUsedNot used

Experience · 2017 – now

Nine years, six roles.

  1. Oct 2024 – now

    Senior Software Engineer · Intellexi · HPB (Croatian Postal Bank)

    Modernising core banking and front-office systems at HPB for new Croatian regulations.

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

  2. Sep 2022 – Jul 2024

    Senior Technical Consultant · CloudSense

    Salesforce builds for three telcos: A1, Telefónica and Liquid Telecom.

    Salesforce · Apex · Lightning Web Components · PDF Butler

  3. Jun 2021 – Sep 2022

    Software Engineer · GlobalLogic

    Two automotive cloud platforms: Stellantis Internet of Vehicles and Daimler’s Mercedes Intelligent Cloud.

    React · TypeScript · Vue.js · Java 11 · Spring Boot

  4. Nov 2019 – Jun 2021

    Software Developer · Maurer Electronics GmbH

    A government platform that tracks tobacco products from factory to shop, to catch illegal ones.

    Java · Spring Boot · React · PostgreSQL · JUnit

  5. Mar – Oct 2019

    Student Software Developer · Sedam IT

    The back end of ZgPark, Zagreb’s pay-parking-by-phone service.

    Java · XML · MS SQL Server · Tomcat

  6. Mar 2017 – Feb 2019

    Student Software Engineer · Ericsson

    4G/5G network code that carries about a billion mobile subscribers.

    C · Java · Erlang · Bash · M4

Education: M.Sc. and B.Sc. in Computer Science · FESB, University of Split · 2014–2019

Full CV

Contact

Let’s build something.

I’m open to AI integration roles where the plumbing matters as much as the model.