Sole Proprietorship
Kraton Systems
$ whoami
Đorđe Lukić — Full-Stack Developer: web development, applications and video surveillance, Valjevo and Mionica
Full-Stack Developer · OCP Java Programmer — Java/Spring Boot, React, IoT systems. Founder of Kraton Systems.
$ cd ./o-meni
About me
// Personal brand, credentials, experience.
oracle.ocp // java se 8
java
spring-boot
react
aws
node.js
python
[ OK ] match: oca · ocp · stack
Đorđe Lukić, Full-Stack Developer, Oracle certified Java programmer from Mionica, Serbia, and founder of Kraton Systems. Years of experience building software independently — from Java/Spring Boot backend systems and React interfaces to a medical Node.js web platform in production, and IoT platforms for monitoring facilities such as farms, pump stations and various industrial plants. Independent work across the whole product cycle: architecture, backend, frontend, databases, deployment and long-term client support — from small business websites to video surveillance systems with dozens of cameras in the field.
// Certifications
// Technologies
- Java
- Spring Boot
- PostgreSQL
- React
- TypeScript
- Python / Flask
- Docker
- REST API
- IoT / Edge systems
- Linux
- Tailscale / Cloudflare
$ cd ./medicascan
Medicascan
// SaaS platform for radiology centers and dental practices.
Medicascan is a cloud platform for radiology centers and dental practices: centers, physicians and patients exchange scans and reports in one place, and the center runs its entire workflow through the same system.
Scans are viewed directly in the browser, with no installation: 2D DICOM tools for contrast, measurements and annotations, and 3D MPR jaw reconstruction across three planes, including large CBCT files.
The business side covers digital referrals with QR codes, a portal for physicians and patients, finances with automatic recalculation of the daily balance, inventory that depletes itself per work order, and a digital patient record.
I built the platform as co-founder and lead developer, on the React, Node.js and AWS stack, with strict data isolation per center.
- SaaS
- DICOM 2D / 3D
- Radiology
- Dentistry
- AWS Cloud
// Full module overview and video demos on the platform's own site.
$ open medica-scan.com ↗
medicascan
enterprise cloud · radiology
- viewer
- 2D · 3D MPR · CBCT
- workflow
- referral · order · report
- storage
- AWS S3 · DynamoDB
- access
- no installation
[ OK ] multi-tenant · zero-trust
$ cd ./google-play
Google Play apps
// Android apps, published 2018–2023.
// Android · Bluetooth · Tools
Arduino Bluetooth Commander
An Arduino controller over Bluetooth with two modes: Remote, a classic remote control for devices, and Stopwatch, timed command sequences that switch Arduino board outputs HIGH or LOW on their own. Includes a built-in tutorial and sample Arduino code, for home automation, DIY projects and robots.
- 5.0★
- rating
- 46
- reviews
- 5K+
- downloads
// Android · Tools
Torch
A stylized flashlight: one tap lights a torch-flame animation with a fire sound, along with the phone's own flash.
- 5.0★
- rating
- 38
- reviews
- 100+
- downloads
// Available on Google Play, developer profile below.
$ open developer-profile ↗$ cd ./kraton
Kraton — digitalization
// IoT platform for infrastructure monitoring. Status: MVP, in active development.
[ DEV ] kraton-core: MVP phase, in active development
Kraton Systems is an IoT platform for monitoring critical infrastructure: farms, pump and irrigation stations, and industrial facilities. A central hub collects telemetry from every device in the field and shows it live on a single dashboard.
Core principle: absence of signal is an alarm. The hub actively pings every node, and a device that doesn't respond within 45 seconds triggers a Telegram alert, even if it failed completely silently.
Field nodes keep working without a connection and recover on their own: they progressively restart Wi-Fi, then NetworkManager, then Tailscale, and sync their data as soon as the connection returns. The hub has the same mechanism for itself, and an independent service watches it from the outside.
The platform is in its MVP phase — not a finished product yet. The current fleet is one central hub and two field nodes, with a local Edge-AI layer for predictive maintenance planned.
- Java 21
- Spring Boot
- PostgreSQL
- Python / Flask
- React
- Tailscale / Cloudflare
- Heartbeat monitoring
- Autonomous network recovery
- check
- every 10 s
- gone dark
- silence > 45 s → alarm
- recovery
- wi-fi → nm → tailscale
- alerts
- telegram
[ DEV ] mvp · fleet: 1 hub + 2 nodes
$ cd ./video-nadzor
Video surveillance in Valjevo and the surrounding area
// Designing and installing video surveillance systems.
// Services
I design and install video surveillance systems built on Frigate NVR — from equipment selection to recording and remote viewing.
- → Frigate NVR systems
- → selecting and installing IP cameras
- → PoE network, UTP/CAT cabling and fiber
- → planning storage and retention periods
[ monitor: live feed ]
// Practical implementation
I do installations with 40+ cameras each, connected into a single system over a PoE network, by cable (CAT) or fiber, depending on the site.
[ OK ] recording active
- cameras
- 40+ per installation
- network
- PoE · CAT / fiber
- storage
- local, on the NVR
- access
- remote, encrypted
[ link: network ]
What I do, how we work and frequently asked questions.
$ cd ./izrada-aplikacija
Website and app development
// Websites, web apps, Android, desktop. I mostly work in Java, and in other technologies where the project needs it.
Websites
Fast, clean websites for companies and entrepreneurs — presentation, services, contact.
- Astro
- Tailwind
- WordPress
Web applications
Business applications with accounts, a database and an API — from idea to deployment.
- Java / Spring Boot
- React
- Node.js
- PostgreSQL
Android apps
Native Android apps in Java, including working with Bluetooth devices and publishing on Google Play.
- Android
- Java
- Bluetooth
Desktop apps
Desktop software in Java — the Medicascan platform started as a JavaFX app in 2023, before its transition to the web a year later.
- Java
- JavaFX
What I do, how we work and frequently asked questions.
$ cd ./testimonijali
Client testimonials
// Medicascan centers and Google Play users.
// Center admin experiences, from medica-scan.com
Dr Miroslav Trifković
Dentist, Ortopaun Center
"Medicascan gave us full control over operations. From automated inventory management to cascading recalculation of the cash balance, the system delivers a precision we couldn't imagine before."
(translated from Serbian)
↗ visit website
Dr Borko Kruskonja
Radiologist, owner of 3D Ortopan Piramida
"The speed of transferring scans through the portal is incomparable to email. Digital referrals have drastically sped up our workflow and cut patients' waiting time at the front desk."
(translated from Serbian)
↗ visit website
Dr Branislav Nadaždin
Oral surgeon, Nadaždin dental practice
"Instant sync on the portal is essential. The doctor no longer waits for emails; you open the patient's profile and the scan is there the moment the center attaches it."
(translated from Serbian)
↗ visit website// Positive reviews, Arduino Bluetooth Commander and Torch
Bojan Pavlovic
★★★★★
"Great app! Very useful. Developers are constantly upgrading this app with the latest features, which make this app top choice for controlling Arduino devices."
Arduino Bluetooth Commander · August 6, 2020
Adel Aly
★★★★★
"Excellent app. Could you please update the application to work with Android version 13."
Arduino Bluetooth Commander · July 2, 2023
A Google user
★★★★★
"Very helpfull app. Did a great job for my arduino project."
Arduino Bluetooth Commander · February 10, 2020
A Google user
★★★★★
"Fantastic App. Beautifull and looks really good."
Torch · February 7, 2020
A Google user
★★★★★
"Great design, nice little app."
Torch · October 23, 2019
A Google user
★★★★★
"Good design! Nice."
Torch · October 24, 2019
$ cd ./cenovnik
Pricing: website, video surveillance, apps
// indicative prices, written offer up front
Website development
Basic build
€300
Video surveillance
Labour (installation and setup)
about €100 per camera
Application development
Roughly
€500 – €10,000+
SEO optimization
Basic package
about €150 a month
// Websites and applications: payment on completion, with no advance, under a contract.
What is included, maintenance and frequently asked questions.
$ cd ./kontakt
Contact
// For collaboration, a quote, or a question — reach out by email or phone.
The fastest way to reach me is email or phone.