43.27° N 20.00° E / Sjenica, Serbia
Websites and software that work with the systems you already run
Kavon is a one-person web development studio in Serbia. I build websites, online stores and web applications for companies in the Balkans and the EU, and connect them to the software you already run, including the Serbian SEF e-invoicing and e-delivery note systems. Messages sent before 5 pm CET get a reply the same day.
Web development in Serbia: what I build
Eight kinds of work, each with an example from a project that is already in use where one exists.
Company websites
A presentation site starts at 100 EUR, with as many pages as you need, and takes 3 to 7 days. An admin panel for editing it yourself, like the one FIDAI Coaching uses, is built on request and priced separately.
Web applications
Records, dashboards and portals for work that has outgrown a spreadsheet, from 300 EUR. BKC Soft's portal takes daily reports from 20+ users.
Online stores
From 350 EUR. At EcoLED, 1,700 products update from the suppliers with no manual entry.
SEF e-invoicing integration
Your existing software sends invoices to SEF, the Serbian government e-invoicing system, without retyping, as the BKC Soft point of sale software does.
E-delivery notes
Send and receive Serbian electronic delivery notes without an ID card reader, from my portal or from your own software.
SEO
Pages and copy built around what people actually type into Google, like the Relax Home blog about prefabricated houses.
Website maintenance
The first year is free. After that it is 10 EUR a month or 100 EUR for the whole year.
UI/UX design
Screens drawn for the phone first, like the e-delivery notes portal, where a new delivery note is the first button you see.
Integrations with Serbian government systems
Companies registered in Serbia send invoices through SEF (the e-invoicing system of the Ministry of Finance) and delivery notes through the eOtpremnice system. Both accept documents only in a prescribed XML format, authenticated with an API key issued to the company. Software that a business has used for years usually cannot do that, and nobody wants to rewrite it from scratch.
For BKC Soft, whose point of sale software is accredited with the Serbian Tax Administration (registration number 88), I built a small service in Go called efakture.exe. The point of sale software calls it on the same computer; the service builds the XML, validates it, sends it to SEF or the e-delivery note system and returns the response. When the government changes the specification, users receive one new file and the point of sale software stays untouched. The service has run since 2023 and now handles close to 50 routes (operations the software can request).
The same software sends a daily cash register report to the BKC Soft portal, where owners see revenue per location next to their SEF e-invoices.
For companies without their own software I built the e-delivery notes portal. A company enters its API key once and sends delivery notes from any device, including a phone, with no card reader. Items are not typed in: the portal reads the QR code on a fiscal receipt and pulls the line items itself. Sending e-invoices from the portal is the next feature I am adding.
Selected projects
Four projects where the website was not the whole job, but part of something the business uses every day.
Online store, 2025
EcoLED
Sells through its own site, Ananas and Shoppster
Stock, prices and new products arrive automatically from 3 suppliers. The same catalog feeds 3 sales channels, each with its own prices, discounts and margins. Customers pay by card through OTP Bank, and businesses order as B2B customers and get a pro forma invoice by email with an IPS QR code for payment.
1,700products, no manual entry
Bookings and payments, 2025
Hotel Lane
Hotel in Sjenica, Serbia
Guests pick a room, book it and pay by card through Halkbank at any hour. Every booking syncs with the front desk software, so the website and reception read the same availability and a room cannot be sold twice.
My own product, 2026
E-delivery notes portal
For companies that ship goods in Serbia
Send and receive electronic delivery notes from a phone, with no card reader. Items are imported by scanning the QR code on a fiscal receipt, and the XML is checked against the government validator before it is sent.
Point of sale, since 2022
BKC Soft
Point of sale software vendor
A website with pricing, a portal where venue owners see daily cash register reports, license management that the software picks up on its own, and the SEF and e-delivery note service.
4systems for the same client
How we work together
- 01
Your brief
Send a few sentences: what your company does, what the site or software should do and when you need it. Messages sent before 5 pm CET get a same day reply with a first estimate and my questions.
- 02
Quote
We agree on the price, the deadline and exactly what is included. Only the domain and hosting are paid up front.
- 03
Build
A presentation site takes 3 to 7 days, larger projects 7 to 20 days. We talk every day during the build, so changes go in while the work is happening.
- 04
Launch and payment
I put the project on the hosting, and you pay the rest after that, as agreed, in installments if you need them.
The full process, step by step
Starting prices
The three most common jobs. Web applications and SEF or e-delivery note integrations are quoted after a conversation; integrations start at around 300 EUR.
from 100 EUR
Presentation website
Pages about the company and its services, as many as you need, plus contact details. Ready in 3 to 7 days. An admin panel costs extra.
from 150 EUR
Business website with a blog
The same as a presentation site, plus a blog with articles on what your customers search for on Google.
350 to 400 EUR
Online store
Catalog, cart and payments. Supplier feeds and extra sales channels are quoted separately.
The domain and hosting are paid separately and up front. If you need a formal invoice, I issue it through a registered company and VAT is added to the price.
Speed you can check
- performance, phone
- 100
- performance, desktop
- 100
- KB whole page
- 100
- KB of JavaScript
- 0
I measured this page with Google Lighthouse on October 7, 2026: performance 100 out of 100 on a phone and 100 on a desktop, accessibility 100 out of 100. The whole page, fonts included, weighs 100 KB and ships no JavaScript at all (0 KB). Once the site is live you can run the same test yourself at pagespeed.web.dev.
Who is behind it
Kavon is me, Kambo, based in Sjenica in southwest Serbia (more about me). I work alone, with no account managers in between: the person who answers your message is the person who writes the code and later maintains the site.
I have built projects for companies in Serbia, Montenegro (Sigma Premium Realty, Galia Apartmani) and Germany (Bralić & Dekić), and I work remotely with clients outside the region. I speak Serbian and English with clients, and I can also communicate in German and Turkish by message. Serbia is on Central European Time, the same clock as Berlin and Vienna; how remote work with EU companies runs is on the nearshore page.
Questions before you get in touch
Who owns the site and the code when the job is done?
You do. The domain is yours, you get access to the hosting I provide, and all the site files are there. If you want the source code as a separate archive, I send it.
Can I get a proper invoice?
Yes. If you need an invoice, I issue it through a registered company and VAT is added to the agreed price. If you do not need one, the price stays as quoted.
We already have accounting or point of sale software. Can it send to SEF?
Send me the name of the software and what it needs to send. For BKC Soft I built a service that takes over sending to SEF and the e-delivery note system, so their software did not have to be rewritten. Whether the same works for yours depends on whether it can call an external service or export invoices to a file, and I check that before I quote.
How much are hosting and the domain per year?
The hosting I provide costs up to about 30 EUR a year, and the domain is paid separately at the registrar's price. Both are paid up front, before work starts, and the rest of the price only after launch.
Send a short brief
Describe what you need in a few sentences. Messages sent before 5 pm CET get a same day reply with a first estimate and the questions that reveal the real scope of the job.