Software studio, Zagreb/Senior engineers/AI-native dev workflows
ByteNest is a senior engineering squad from Zagreb. We built production systems for years before AI, and today we run AI-native development workflows on top of that experience. Your product reaches the market sooner and costs less to build, with the engineering standard intact.
Selected work
Profit analytics for collision repair shops, with an AI assistant on Amazon Bedrock. Built end to end for an Australian partner.
Photoreal 3D apartments that buyers walk through before they are built, in any browser. Our own product.
A booking app and salon dashboard for barbershops. We designed the architecture and lead the build.
Citizens report potholes and broken lights with a photo and GPS. We rewrote the app in Flutter for Promet i prostor.
Road crews log interventions with photos, GPS and road chainage, even with no signal. Built for Promet i prostor on their own GIS platform.
Picture cards with a parent's photos and voice, and a sentence book that speaks correct Croatian, for autistic children.
Scans a hair product's ingredient list and explains it in Croatian, with the owner's engine running offline on the phone.
Clients: MAF, Revlum
We rescued a non-functional iOS SDK for MAF and managed the Revlum Offerwall SDKs.
Reservations and a live floor plan. An assistant takes plain Croatian commands and runs the same checks as a manual booking.
Client work, not public yet. Happy to talk about it on a call.
Wedding and event invitations. Guests reply from one shared link, no app or account; the host's dashboard updates live.
Client work, not public yet. Happy to talk about it on a call.
Built on the price lists Croatian chains must publish: prices from 11 chains, each in its own format, matched product by product.
Client work, not public yet. Happy to talk about it on a call.
How we work
Our engineers were shipping production systems for years before AI tools existed. Today we run AI-native development workflows on top of that experience: every task starts from a written spec, and every change is reviewed independently and tested before it ships.
The tools are available to everyone. Knowing what to build, how to structure it and when a result is wrong takes years, and that is what you hire us for.
We build AI into products, too. Pulse's assistant runs Claude on Amazon Bedrock in Australia, and every number it writes comes from SQL.
Engagement models
A free consultation, then a written spec and a fixed quote.
An ongoing senior team, monthly, for a product that keeps growing.
We take over a stuck or broken codebase, like the MAF iOS SDK.
Who you work with
Engineering lead with 8 years in software: mostly Flutter, early years in .NET and SQL, web throughout. He founded ByteNest in 2023 and is product owner and architect on every client project: the person you talk to, and the person accountable for what ships.
When a project needs more hands, Ivan brings in engineers he has worked with before and whose work he has seen hold up in production. You never get whoever happens to be free: the talent on your project is already filtered. Ivan stays your point of contact and the architect throughout.
The founder's track record
Before and alongside ByteNest, Ivan built and led the work below as an employee of KING ICT, Q Agency and Four of them LLC. These are not ByteNest projects. They are where the experience on your project comes from.
2019 to 2020 · Full stack .NET developer · KING ICT
The next-generation emergency management system used by every 112 call centre in Croatia. Operators see where a caller is in real time, work on satellite imagery and coordinate the dispatch of police, fire and medical services.
It is integrated with the call centres' Cisco telephony (Cisco Unified Communications Manager), so an incoming 112 call is handed from the phone system to the same application the operator dispatches from.
Ivan worked on it across the stack for a year and a half: the operators' desktop client in C# and WPF, the backend services behind it on gRPC and MassTransit, and the designs for both, worked out with the business analysts.
A government system, so there are no public screens to show.
2023 to 2025 · Mobile Team Lead · Four of them LLC
Germany's pharmacy app: e-prescriptions, online ordering and a pharmacy finder across 7,500+ partner pharmacies. Ivan led and mentored the 15 mobile developers behind it, in Flutter and native iOS and Android, while it grew from 100k to over a million downloads.
1M+ downloads across both stores, rated 4.6 on each.
Google Play (opens in a new tab)App Store (opens in a new tab)
2022 · Technical lead · Q Agency
The digital collector album that REWE, one of Germany's largest supermarket chains, ran for the 2022 football World Cup. Shoppers scanned the 35 collector cards of the German national team with their phone to fill the album and unlock a golden fan card. Ivan bootstrapped the Flutter app, led the team that built it and worked on the card scanning: image recognition and OCR on the device.
A nationwide campaign in REWE stores across Germany, October to December 2022.
App Store listing, archived (opens in a new tab)The campaign ended, so the app has left the stores.
2022 to 2023 · Lead developer · Q Agency
The app of Via Riyadh, a luxury shopping, dining and hotel destination in the Saudi capital. Ivan was the lead developer: in direct contact with the client, coordinating the development and business analysis teams, and running the pipeline that took the app to both stores.
Led the mobile build from the first commit to production on iOS and Android.
viariyadh.com (opens in a new tab)Google Play (opens in a new tab)App Store (opens in a new tab)
2021 to 2022 · Flutter developer · Q Agency
A closed social network for a company's employees: a news feed, a people directory, kudos, stories and an anonymous shoutbox. Jenz started as a Q Agency internal tool and grew into a company of its own. Ivan designed and built features in Flutter with the team, supported production and rolled out new releases.
20,000+ users reported for Jenz.
2020 to 2021 · Full stack developer · KING ICT
The central platform of Croatia's national water authority, for monitoring and managing water use and extraction across the country.
National scale: one platform for all of Croatia.
2021 to 2022 · Flutter developer · Q Agency
Two more production mobile apps from the same years at Q Agency. Ivan designed and built features in Flutter with the team, supported production and rolled out new releases.
Three apps in production across those two years, counting Jenz.
2023 · Designed and implemented · Q Agency
A company-wide internal tool that answered questions about the company's documentation in plain language. The documents were embedded into a Pinecone vector index, and a self-hosted model answered from what the search retrieved.
An early RAG system, built in 2023 when the pattern was new.
Screens come from each app's public store listing. The products belong to their publishers and appear here as the founder's work history.
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Prefer plain email? Write to hello@bytenest.hr.