Freelance software engineer · Serbia

Software that runs your business, not the other way around.

I build custom software, integrations and payment systems for companies that need technology to just work — end to end, from the first line of code to a system your team relies on every day.

See my work Get in touch
Portrait of Alexander Gorbunov

Fuel logistics, payments, steel production, music streaming — different industries, same job: build the system the business runs on, and make it hold.

100%
job success — every contract finished
5+
years shipping production systems
1000s
B2B users on systems I built
5
products live today, in four industries

Products I built, in production

01 · What I do

01

Custom software & products

I take a business problem and build the product around it — backend, web and mobile — from first requirements to a live system, and I keep maintaining it after launch.

Read more → 02

LLM & AI agents

I build LLM features into real products — assistants, retrieval over your own documents with self-hosted models, and agent pipelines that carry a multi-step task through to a result instead of just answering a question.

Read more → 03

Integrations & automation

I connect the systems you already run — accounting, logistics, suppliers — and automate the manual work between them. Fewer spreadsheets, fewer copy-paste mistakes, faster operations.

Read more → 04

Payments & acquiring

I integrate payment processing and acquiring into your product, so customers can pay you the way they expect — securely, and without surprises at checkout.

Read more →
What I build →
02 · Recent work

Products in production

B2B fuel cards · Russia

Benzigo

benzigo.ru →

Built the customer-facing app used by over a thousand fleet companies, plus an autonomous Go bot that executes thousands of card operations directly on the fuel provider's own portal — blocking, freezing and balance reads, unattended, across several Docker instances.

GoRedisVueAutonomous bots
Read more →
Fleet compliance · Full-stack

E-PL

e-pl.ru →

Sole engineer on a fleet compliance platform, end to end: pre-trip breathalyzer checks over Bluetooth, e-waybills with qualified CryptoPro signatures, an online shop with acquiring, and CDEK delivery integration.

GoFlutterBluetooth LEAcquiringCDEK
Read more →
Co-founder & CTO

fjalla

fjalla.net →

Founded and wrote the first version of a per-play music streaming platform alone — Go and Fiber over PostgreSQL, Redis and RabbitMQ — then led the team that grew around it.

Go / FiberRabbitMQFlutterArchitecture
Read more →
Freelance · Full-stack

Cinemusic

Visit site →

Largest contributor to the Go backend of a music-licensing platform used by TV channels — payments, subscriptions and RAO rights certificates — plus AI music generation via Suno in the Flutter desktop app.

GoFlutter DesktopSuno APIPayments
Read more →
Products in production →
03 · How I work

Why clients hand me the whole thing

There are a lot of good developers. What decides a project is rarely who writes the cleverest code — it is who stays until the thing is live, tells you the truth on the way there, and can be checked by someone other than himself.

01

I finish what I start

100% job success, across every contract I have taken. No project abandoned halfway, no half-built system handed back with an apology. If I take the work, I stay until it runs in production — and I am still there after launch, when the real problems show up.

Verified on Upwork
02

Verified, not just claimed

Everything on this page can be checked by someone who is not me. I speak at engineering conferences in front of rooms full of people who would notice if I were bluffing, and I build for heavy industry — where software failing is not a bad sprint, it is a stopped production line.

Talks & recordings Smart Steel Technologies
03

I own the outcome

As co-founder of fjalla I was the one holding the decisions, the mistakes and the consequences — and I carried the platform from a blank page to production and real users. I bring the same posture to client work: the outcome is mine, not just the tickets assigned to me.

fjalla.net
04

I communicate like a partner

English, German and Serbian — and years of explaining hard technical trade-offs from a stage, to engineers and to people who do not write code. You will always know where your project stands, in language you can act on. No silence, and no surprises at the end of the month.

See me on stage

Shipped. Owned. Verified. Every line of that is checkable on this page — and that is the part I would want, if I were the one hiring.

Start a conversation
04 · Full-time experience

Where I have worked

  1. 2024–2026

    Smart Steel Technologies

    Software Engineer

    Owned the materials-allocation product end to end; promoted within 14 months.

  2. 2022–2024

    NtechLab

    Frontend Developer

    Led the Flutter upgrade and the move to trunk-based development.

  3. 2022

    Webware Internet Solutions

    Software Engineer

    Sole developer of an internal SPA, from requirements to production.

  4. 2021–2022

    Lins-Intek

    Frontend Developer

    Delivered payment, subscription and admin modules for client apps.

05 · Speaking

On stage

06 · About

A bit about me

5+ years building production software end to end — backend, web and mobile — for companies that need systems that don't break. I'm also co-founder and CTO of fjalla, a music-streaming platform: I wrote the first version of it alone, and still own the architecture as the team has grown around it.

Based in Serbia, registered as an official business — work with me comes with contracts and invoices, no informal arrangements. I work in English, German and Serbian.

Also comfortable with
GoTypeScriptFlutterPostgreSQLKafkaAI agents & LLM integration
Education

Computer Science — IU International University of Applied Sciences

07 · Get in touch

Tell me what you're building

Describe the problem, not the tech stack — I reply within a day.

Or reach me directly
Upwork · upwork.com