Karlo Vuk, Developer in Zagreb, Croatia
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Karlo Vuk

Verified Expert  in Engineering

Bio

Karlo is a skilled software developer with a master's degree in software engineering and more than seven years of professional experience. He has created and maintained desktop and web applications using .NET and related technologies for various industries, including healthcare, banking, government, and more.

Portfolio

BaxEnergy Italia SRL - Main
C#, MQTT, Message Queues, Architecture, Back-end Architecture, Cryptography...
REJUV AVE, LLC
React, .NET, Azure, TypeScript, JSON Web Tokens (JWT), SQL, Stripe, Twilio, CSS...
Lone Star Analysis
C#, Windows Presentation Foundation (WPF), C#.NET, Agile, Desktop...

Experience

  • Microsoft Visual Studio - 20 years
  • Windows - 20 years
  • Visual Studio - 20 years
  • .NET - 13 years
  • C# - 13 years
  • Windows Forms (WinForms) - 12 years
  • Model View ViewModel (MVVM) - 12 years
  • Windows Presentation Foundation (WPF) - 10 years

Availability

Full-time

Preferred Environment

Visual Studio

The most amazing...

...bug I found and resolved almost caused half a million euros in financial damages.

Work Experience

Senior C# Developer

2025 - 2025
BaxEnergy Italia SRL - Main
  • Developed mock machine exposing data via OPC UA in Node.js.
  • Implemented integration via OpenVPN by tunneling SSH.
  • Added team-shared Docker containers via Docker Compose.
Technologies: C#, MQTT, Message Queues, Architecture, Back-end Architecture, Cryptography, TimescaleDB, PostgreSQL, Timescale, Docker, Continuous Integration (CI), Continuous Delivery (CD), CI/CD Pipelines, Next.js, Node.js, OPC UA, OpenVPN, SSH, SCADA, Bash, Linux, Containers, CSS3, .NET 9, Amazon Web Services (AWS), Object-oriented Programming (OOP), Scripting, Web Services, Cloud Platforms, REST, Authentication, Open APIs, Documentation, OAuth 2, JavaScript, API Gateways, Kubernetes, OpenAPI, OAuth, Microsoft Copilot, Development, .NET 8

Full-stack .NET Core & React Developer

2023 - 2023
REJUV AVE, LLC
  • Optimized performance by reorganizing data models and adding indexes, which also led to lowering serving costs.
  • Managed and streamlined publishing of apps to Azure or Docker.
  • Fixed bugs and improved UI/UX by improving visual consistency throughout user flow.
Technologies: React, .NET, Azure, TypeScript, JSON Web Tokens (JWT), SQL, Stripe, Twilio, CSS, Material UI, HTML5, Back-end, Node.js, Enterprise Application Development, User Interface (UI), UX Design, UI Design, Codebase Development, Static Analysis, Technical Architecture, Enterprise Business Architecture, Enterprise Architecture, Web Applications, Web Development, Architecture, Repository Pattern, Microservices, Databases, LINQ, ASP.NET, Entity Framework Core, GitHub, Software as a Service (SaaS), New Products, RESTful Microservices, Graphical User Interface (GUI), Redux, RESTFul APIs, ASP.NET Core, Git, Swagger, Azure SQL, CSS3, Figma, JWT/AUTH, AutoMapper, .NET 9, Object-oriented Programming (OOP), Scripting, Web Services, Cloud Platforms, REST, Authentication, Open APIs, JavaScript, Development

C# .NET | WPF Developer

2021 - 2023
Lone Star Analysis
  • Optimized long-running simulation processes to improve both CPU time and memory footprint.
  • Tracked and fixed bugs using Jira as a tracking tool.
  • Implemented new features to enrich customer experience.
Technologies: C#, Windows Presentation Foundation (WPF), C#.NET, Agile, Desktop, Software Architecture, Material UI, Business Analysis, Enterprise Application Development, User Interface (UI), UX Design, UI Design, Code Review, Architecture, Source Code Review, Codebase Development, Static Analysis, Finance, Data Processing, Databases, LINQ, GitHub, .NET Framework, CSV, Desktop App Development, Software as a Service (SaaS), Graphical User Interface (GUI), Git, Scrum, Figma, .NET 9, SVG, Object-oriented Programming (OOP), Scripting, Authentication, Documentation, SQLite, Development

.NET WPF Engineer

2020 - 2021
Tesco Controls Inc.
  • Developed customizable large-scale data-grid-based catalog management.
  • Improved the customer workflow, where customers can now monitor, filter, and arrange large sets of data with more ease.
  • Laid the foundation for future feature implementation. By making elements generic, less tech-savvy team members can expand on my work by copying and modifying it.
Technologies: C#, Windows Presentation Foundation (WPF), XAML, Windows, Microsoft Visual Studio, .NET, Desktop, Enterprise Application Development, User Interface (UI), UX Design, UI Design, Codebase Development, Static Analysis, Databases, LINQ, Microsoft Excel, GitHub, .NET Framework, SQL, Desktop App Development, Git, Object-oriented Programming (OOP), Scripting, Documentation, Development

Windows Desktop App Developer

2020 - 2020
Accountable2You LLC
  • Identified and fixed the bugs reported through Jira.
  • Improved hit accuracy when doing image searches across combinations of browsers and search engines.
  • Enhanced performance by optimizing a tree search algorithm.
Technologies: C#, Windows Forms (WinForms), Windows Presentation Foundation (WPF), Automation, UI Automation, Web Scraping, Tracking, User Interface (UI), UX Design, UI Design, Codebase Development, Static Analysis, Architecture, LINQ, GitHub, .NET Framework, Desktop App Development, Software as a Service (SaaS), Graphical User Interface (GUI), RESTFul APIs, Git, Object-oriented Programming (OOP), Scripting, Signature Verification, SQLite, Development

Software Developer

2016 - 2020
MCS grupa d.o.o.
  • Developed modules for an existing web platform used for tracking work in the field of medicine.
  • Created a makeover of a desktop client application used to sign data submitted via web forms.
  • Designed a shell for sustainable maintenance of a VPN client (automatic reconnecting and diagnosing).
Technologies: jQuery, Entity Framework, Windows Presentation Foundation (WPF), Active Server Pages (ASP), Windows Forms (WinForms), Microsoft SQL Server, .NET, XAML, Model View Controller (MVC), Model View ViewModel (MVVM), Windows, Microsoft Visual Studio, C#, REST APIs, ASP.NET MVC, ReSharper, HTML, .NET Core, Cloud, JSON Web Tokens (JWT), React, Healthcare, Health, Desktop, Software Architecture, Medical Software, Full-stack, Front-end Development, Full-stack Development, API Integration, APIs, Front-end, Cloud Infrastructure, CSS, HTML5, Back-end, PDF, JSON/XML Schemas, Business Analysis, Enterprise Application Development, JSON, User Interface (UI), UX Design, UI Design, Large-scale Projects, Architecture, Code Review, Source Code Review, Codebase Development, Static Analysis, Technical Architecture, Enterprise Business Architecture, Enterprise Architecture, Electronic Health Records (EHR), Web Applications, Web Development, Finance, Finance APIs, Data Processing, Cloud Services, Repository Pattern, Microservices, Databases, LINQ, Microsoft Excel, Solution Architecture, ASP.NET, .NET Framework, Windows Communication Foundation (WCF), SQL, CSV, Digital Imaging, Desktop App Development, FTP, IIS, Software as a Service (SaaS), New Products, WebSockets, RESTful Microservices, Graphical User Interface (GUI), RESTFul APIs, ASP.NET Core, Git, Dapper, Postman, Swagger, Agile, CSS3, JWT/AUTH, AutoMapper, SVG, Bootstrap, Object-oriented Programming (OOP), Scripting, Web Services, Pharmacy, REST, Authentication, Healthcare Software, Open APIs, Documentation, .NET Core 3, Signature Verification, Blazor, JavaScript, SQLite, API Gateways, Grafana, OpenAPI, Development

Software Developer

2011 - 2016
Ekobit d.o.o.
  • Supported a program for calibration, preparation, and remote monitoring of devices for measuring and controlling indoor air characteristics.
  • Created new and modified existing order forms on client management sites.
  • Designed entry forms used for statistical analysis.
  • Contributed to the process of bank card creation, issuing and managing, and processing and monitoring transactions.
Technologies: Model View Controller (MVC), jQuery, JavaScript, Windows Forms (WinForms), Windows Presentation Foundation (WPF), Microsoft SQL Server, .NET, XAML, Entity Framework, Active Server Pages (ASP), Model View ViewModel (MVVM), Windows, Microsoft Visual Studio, C#, REST APIs, ASP.NET MVC, ReSharper, Python, Desktop, Software Architecture, Full-stack, Front-end Development, Full-stack Development, Front-end, CSS, Business Analysis, Enterprise Application Development, User Interface (UI), UX Design, UI Design, Architecture, Codebase Development, Static Analysis, Enterprise Business Architecture, Enterprise Architecture, Web Applications, Web Development, Finance, Finance APIs, Data Processing, Repository Pattern, Databases, LINQ, Microsoft Excel, ASP.NET, .NET Framework, Windows Communication Foundation (WCF), SQL, CSV, Hardware, Desktop App Development, FTP, New Products, Graphical User Interface (GUI), Scrum, Agile, C#.NET WinForms, SVG, Object-oriented Programming (OOP), Scripting, REST, C++, Documentation, Signature Verification, SQLite, Development

Experience

Dosimeter Interface

Software for reading and plotting data (user interface) from an ionic radiation measuring device (dosimeter). It communicates with the device on a binary level, interprets, and plots the read data, configuring device parameters.

Smart Card Desktop Client for Healthcare Workers

Healthcare workers must register their work and sign it using government-regulated smart cards upon supplying patients with government-funded services and pharmaceutical products. The desktop client enables connecting to the required VPN and signing messages (prescriptions, diagnosis, etc.), even for web applications.

Management Application for a Major Banking Group

An enterprise application for managing bank cards. The application tracks the entire lifespan of a bank card including creating, issuing, and processing transactions. The app also groups those transactions and calculates fees between different banks based on roles (card issuer and card acquirer).

Web Forms for the Criminal Justice Department

Developed a series of web forms for filing a specific profile of cases for the criminal justice department. The forms were dynamically adjusted based on a provided rule set as they were being filled out.

Interface for Network of Air Quality Devices

Certain facilities require superior air quality control. The client produces devices that measure and control air quality based on given parameters (temperature, humidity, airflow, etc.). These devices need calibration and monitoring. The interface application gives live information about the device's status and measurements as well as support for device parameter control and firmware update via the network.

Healthcare Integrations

Provided integration between several healthcare-related systems regarding patient health status, report handling, invoicing, and user administration. I also provided integration with health insurance services digitally signing prescriptions, doctor referrals, and medical history.

Foot Condition Image Detection

An AI model is trained via supervised learning from data provided by a specialist. A specialist labels conditions found on digital images. The collection is then used to train the AI model to diagnose various foot conditions. After diagnosis, a treatment is recommended with estimated recovery and cost (provided by the client).

Education

2007 - 2013

Master's Degree in Software Engineering

Faculty of Electrical Engineering and Computing - Zagreb, Croatia

Certifications

MARCH 2014 - MARCH 2016

MCSD: Windows Store Apps Using C#

Microsoft Corporation

Skills

Libraries/APIs

Entity Framework, React, REST APIs, LINQ, AutoMapper, Open APIs, OpenAPI, Windows Forms (WinForms), jQuery, Node.js, Web API, Stripe

Tools

Visual Studio, Microsoft Visual Studio, C#.NET WinForms, ReSharper, Docker Hub, Microsoft Excel, GitHub, Git, Dapper, Postman, Figma, Microsoft Copilot, Automic (UC4), Blender, MQTT, OpenVPN, Grafana

Languages

C#, JavaScript, XAML, C#.NET, HTML, CSS3, Active Server Pages (ASP), SQL, Excel VBA, CSS, TypeScript, Python, HTML5, Visual Basic for Applications (VBA), C++, Bash

Frameworks

Windows Presentation Foundation (WPF), .NET, ASP.NET Core, .NET Core, ASP.NET, Entity Framework Core, .NET 9, .NET 8, ASP.NET MVC, ASP.NET Web Forms, JSON Web Tokens (JWT), Material UI, Razor, Redux, Swagger, Bootstrap, OAuth 2, Blazor, Unity, ML.NET, Next.js

Paradigms

Scrum, Model View ViewModel (MVVM), Desktop App Development, Object-oriented Programming (OOP), REST, Model View Controller (MVC), Agile, UX Design, UI Design, Microservices, Automation, Back-end Architecture, Continuous Integration (CI), Continuous Delivery (CD)

Platforms

Windows, Desktop, Linux, Docker, Azure, Amazon Web Services (AWS), Twilio, Kubernetes

Storage

JSON, Databases, Azure SQL, SQLite, Microsoft SQL Server, SQL Server 2016, JSON/XML Schemas, MySQL, PostgreSQL

Industry Expertise

Healthcare

Other

Cloud, API Integration, APIs, Back-end, Windows Store, User Interface (UI), Code Review, Architecture, Source Code Review, Codebase Development, Static Analysis, Web Applications, Web Development, Data Processing, Repository Pattern, .NET Framework, CSV, New Products, RESTful Microservices, Graphical User Interface (GUI), RESTFul APIs, JWT/AUTH, SVG, Scripting, Web Services, Authentication, Documentation, .NET Core 3, Signature Verification, Development, Excel Expert, Health, Software Architecture, Medical Software, Full-stack, Front-end Development, Full-stack Development, Front-end, Cloud Infrastructure, PDF, Business Analysis, Enterprise Application Development, Large-scale Projects, Technical Architecture, Enterprise Business Architecture, Enterprise Architecture, Electronic Health Records (EHR), Finance, Finance APIs, Cloud Services, Solution Architecture, Windows Communication Foundation (WCF), FTP, IIS, Software as a Service (SaaS), WebSockets, CI/CD Pipelines, Cloud Platforms, Pharmacy, Healthcare Software, API Gateways, OAuth, IoT Security, Web Scraping, UI Automation, Tracking, Hardware, Digital Imaging, Artificial Intelligence (AI), Vite, Message Queues, Cryptography, TimescaleDB, Timescale, OPC UA, SSH, SCADA, Containers

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