Dinis Vieira, Developer in Lisbon, Portugal
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Dinis Vieira

Verified Expert  in Engineering

Xamarin.Forms Developer

Lisbon, Portugal
Toptal Member Since
May 26, 2022

Dinis is a senior software developer with 12 years of experience currently focusing on mobile development with Xamarin. In the past, he has also done native and hybrid mobile development as well as web development. Dinis has served as the team lead of small development teams throughout the last few years and helped my managers and companies with key technology decisions.


Xamarin, Xamarin.Forms, C#, iOS, Android, XAML, Xamarin.UITest, .NET MAUI
Xpand IT
Xamarin, Xamarin.iOS, Xamarin.UITest, Xamarin.Android, Xamarin.Forms, C#, XAML...
Gfi Portugal
Windows Presentation Foundation (WPF), Windows Store...




Preferred Environment

Windows, Visual Studio, Git, MacOS

The most amazing...

...project I've been involved in is a partnership with Mercedes-Benz to create a custom-built telemetry app for the legendary big-wave surfer Garret McNamara.

Work Experience

Lead Mobile Developer

2017 - PRESENT
  • Served as the lead developer for mobile apps for iOS and Android using Xamarin.Forms.
  • Suggested and designed new apps to replace older ones. The new apps managed to drastically increase the development cycle.
  • Implemented automated UI tests and CI/CD and helped with other key tech decisions.
Technologies: Xamarin, Xamarin.Forms, C#, iOS, Android, XAML, Xamarin.UITest, .NET MAUI

Tech Lead Developer

2013 - 2017
Xpand IT
  • Worked across several projects and customers, usually as the team lead developer.
  • Led training and workshops inside the company and for customers and other organizations, including universities.
  • Developed mobile apps using Xamarin.Native, Xamarin.Forms, Android (Java), and iOS (Objective-C); developed websites with .Net MVC; and contributed to other R&D projects.
  • Created a real-time telemetry solution for McNamara and Mercedes using Android and Azure.
  • Worked as a team lead developer for a USA-based customer building an app for mobile analytics (Windows Store app).
Technologies: Xamarin, Xamarin.iOS, Xamarin.UITest, Xamarin.Android, Xamarin.Forms, C#, XAML, ASP.NET, Android, iOS, Objective-C, Java, Azure

Research and Development

2011 - 2013
Gfi Portugal
  • Developed an interactive itineraries experiment using Microsoft Kinect and Google StreetView. This was showcased at an international exhibition in Lisbon.
  • Developed several apps and PoCs with Phonegap, Kinect, iOS, Android, Windows Phone, and Windows Store Apps.
  • Organized several geek/tech events, helped define internal programming practices and methodologies, and presented workshops on Windows Store apps and mobile web development.
  • Helped sales managers with pre-sales initiatives.
Technologies: Windows Presentation Foundation (WPF), Windows Store, Universal Windows Platform (UWP), jQuery Mobile, Microsoft Kinect, Windows Phone, PhoneGap, iOS, Android, Java, Objective-C

Mobile App for Safety Management

This is an ongoing project in which I’m developing an app for Android and iOS using Xamarin.

The project already existed in an unfinished state when I started working on it, so I started analyzing how to improve it. As a result, we built a new app that has completely replaced the old one while using improved maintainability techniques and UI/UX.

Nutrition Platform and Service

Headed the high-level design and architecture of the entire solution.

Developed the Android and iOS mobile apps that allowed users to access the platform and the back end (Azure/.Net MVC) used by nutritionist professionals.

Mobile Banking App

Served as a team lead and developer of two mobile banking apps, one for specific users and the other for companies.

The app was developed with Xamarin for Android, iOS, and Windows Phone; code sharing was done for the three platforms and sharing between the two app user types, which were similar in design and logic.

This app was used as a case study by Xamarin.

Mobile Analytics App

Led and developed a Windows app for a mobile analytics platform that brings data and business intelligence to the next generation of users. The application allows for the interactive handling of all the connected data.

During this project, I worked primarily remotely while maintaining constant contact with my team and other company teams. I also relocated to the USA a couple of times to work directly in the office.

Real-Time Telemetry App/Service

Mercedes-Benz exclusively developed a unique surfboard for legendary big wave rider Garrett McNamara's quest to break his own world record in Nazaré, Portugal.

I created custom-built telemetry for Garret McNamara as part of this project, and among other findings, the top speed achieved was 62.4 kilometers per hour.

Kinect Experience

Interactive itineraries using Microsoft Kinect and Google Streetview. Users can activate navigation with body gestures and find out more information about sights, watch videos, and activate sounds. Developed while at GFI Portugal and first presented at the Turismo de Portugal booth at International Tourism Exhibition (Portugal) for Turismo de Portugal.
2007 - 2011

Bachelor's Degree in Computer Science

NOVA University Lisbon - Lisbon, Portugal


Xamarin Certified Developer



Microsoft Certified Solution Developer



Microsoft Certified Professional



Xamarin.iOS, Xamarin.Android, jQuery Mobile


Visual Studio, Git


.NET MAUI, Xamarin.UITest, ASP.NET, Windows Presentation Foundation (WPF), Microsoft Kinect, PhoneGap


XAML, C#, Objective-C, Java


Xamarin, Mobile, iOS, Android, Universal Windows Platform (UWP), Windows Phone, Web, Windows, MacOS, Azure


Xamarin.Forms, Software, Windows Store

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