Antonio Seric, Developer in Split, Croatia
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Antonio Seric

Verified Expert  in Engineering

Xamarin.Forms Developer

Split, Croatia
Toptal Member Since
May 5, 2016

Antonio is a senior software developer with experience in developing all kinds of applications (web, desktop, mobile, and IoT) in the C# .NET framework, Antonio also has developed Android and iOS applications in C# (Xamarin). He works equally well on his own and in small/large teams to help you with your project from ideation to production. In his free time, Antonio researches new technology and perfecting his current ones.


C#, C#.NET, Push Notifications, Microsoft SQL Server, ASP.NET
Azure, Xamarin, Java, Android, .NET, C#, C#.NET, Push Notifications...
SQL, Assembler, C, C#, C#.NET, Microsoft SQL Server, ASP.NET




Preferred Environment

Xamarin, Windows, Azure, Git, SourceTree, Visual Studio, C#

The most amazing...

...thing I've coded is a whole business solution in C#, from web application (front end and back end), workers to mobile application and IoT embedded device.

Work Experience

Software Architect

2017 - PRESENT
  • Developed a web application on Azure.
  • Implemented CI/CD using GitLab, Jenkins, and Azure.
  • Built a C#-based web application.
  • Installed a mono-console microservices on the Ubuntu server.
  • Implemented Xamarin Forms for an Android and iOS application.
  • Implemented Xamarin native binding for Android and iOS library.
Technologies: C#, C#.NET, Push Notifications, Microsoft SQL Server, ASP.NET

Owner | Developer

2013 - 2018
  • Customized an Android tablet launcher with navigation that was specifically built for curriculum use for the teachers and students in a primary school.
  • Created an Android application generator service using C# and application templates in Android Java.
  • Managed the continuous integration and deployment for an MVC5 application for testing of safety valves.
  • Created a reusable template library for MVC 5 application with authentication and DAL and an Android library client for connecting to a WEB API.
  • Built a simple torrent client using MonoTorrent.
  • Developed a web scraper with states for downloading files from sites.
  • Created an IE BHO extension to inject JavaScript into any site.
Technologies: Azure, Xamarin, Java, Android, .NET, C#, C#.NET, Push Notifications, Microsoft SQL Server, ASP.NET

Student Developer

2008 - 2014
  • Created a data logger device and server for collecting information about the intensity levels of solar radiation and temperature.
  • Developed a converter RS232 to DALI in ATMEL assembler.
  • Created a hotel-booking system for the hotel's internal use.
  • Developed a control step motor over Ethernet.
  • Developed Arduino controllers for two propellers in order to get stability for a simulating drone.
  • Worked as a professor assistant for projecting digital systems using Verilog.
Technologies: SQL, Assembler, C, C#, C#.NET, Microsoft SQL Server, ASP.NET

Software Developer

2011 - 2013
IT Sistemi
  • Distributed a large system with two different databases on which there are four desktop clients and two web clients.
  • Gathered and sorted banking account information from a large database.
  • Created a dynamic report engine that generates RDLC.
  • Supported a multipage TIFF for a scanning app.
  • Developed an Android app for checking SVN changes.
  • Built an Android app that connects to a CMIS protocol for document management.
Technologies: Reporting, T-SQL (Transact-SQL), .NET, C#, C#.NET, Push Notifications, Microsoft SQL Server, ASP.NET

Take Remote Photos with Your Mobile
The Project's Three Main Parts:
1. Mobile apps (iOS, Android)
2. Server microservice architecture (photo column)
3. Azure services

Project Details:
• The mobile apps are built with Xamarin.Forms.
• Gstreamer is used for live preview and it's built with the Android NDK and SDK which was also used in the Xamarin project.
• The photo column software controls the cameraand sends environment and power data to Azure.
• It also provides camera access (live preview and photo taking) to mobile clients.
• Various Azure cloud services were used: IoT Hub, SQL Database, Web App, and Blob Storage.

Android POS Client with REST API Service for an Old MS Dos App

Built a REST API service to communicate with a DOS app written in Pascal so that reading and writing files on the file system could be done.

The Android app is now a modern client for placing orders on a Bluetooth printer. it is build in with Android SDK java.

High-traffic Web App

An MVC5 web app that was built with ASP.NET MVC and tested with VSTS web test with 20,000 concurrent users who are also trying to buy tickets.

Mobile Social Network

This project dealt with Xamarin Forms apps (Android and iOS) along with a full custom design. REST was used for the Web API and ASP.NET MVC for the back-end for administrators.


XAML, C#, C#.NET, C, Java, Verilog, JavaScript, T-SQL (Transact-SQL), YAML, Assembler, SQL, CSS


ASP.NET Web API, ASP.NET MVC 5, ASP.NET, Android SDK, .NET Core, ASP.NET Core, .NET, .NET Micro, Mono


Xamarin.iOS, Xamarin.Android, LINQ, Facebook API, jQuery


SourceTree, Microsoft Visual Studio, Git, Azure DevOps Services, Visual Studio 2019, Azure IoT Suite, Android NDK, Jenkins, MSBuild, GitLab, Subversion (SVN), Android Studio, VisualSVN, Trello, Visual Studio, GitLab CI/CD


Desktop App Development, Web Application Architecture, Azure DevOps, Unit Testing, Design Patterns


Windows, Xamarin, Ubuntu Linux, Windows Server, BlackBerry, iOS, Azure, Android, Android TV


Azure Websites, Microsoft SQL Server, Azure SQL, Azure Blobs, SQLite, MySQL


Xamarin Studio, Xamarin.Forms, Push Notifications, .NET 6, Performance Optimization, Ubuntu Server, DNS, IIS, Internet of Things (IoT), Server Administration, Mobile Apps, Reporting, Android Wearables

2004 - 2010

Master's Degree in Computer Engeneering

University of Split, Faculty of Electrical Engineering, Mechanical Engineering, and Naval Architecture | FESB - Split, Croatia


Programming in C#


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