Denis Jesus Gonzalez Sanchez, Developer in Mexico City, Mexico
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Denis Jesus Gonzalez Sanchez

Verified Expert  in Engineering

Windows Communication Foundation (WCF) Developer

Mexico City, Mexico
Toptal Member Since
September 12, 2018

Denis is a certified C# specialist and MS certified professional with over a dozen years of experience in several programming languages and business domains. He thrives in challenging situations and easily becomes well-adjusted to new work environments. Denis possesses a comprehensive technical background that extends beyond software development, covering R&D and managerial activities. He also has a degree in modern languages.


Windows Services, Windows Forms (WinForms), Web Services, IIS, .NET, Azure...
Knowtion SA de CV
MongoDB, Microsoft SQL Server, Git, Ruby, Jenkins...
Clinical Champion
Amazon S3 (AWS S3), MongoDB, Windows Communication Foundation (WCF)...




Preferred Environment

Jenkins, Git, Visual Studio Code (VS Code), Visual Studio, .NET Core, SQL, HTTP REST

The most amazing...

...project I've coded was a data synchronization system that allowed for a centralized database for about 500 points of sale distributed around the country.

Work Experience

Software Developer

2019 - PRESENT
  • Oversaw the support for the legacy Windows Forms App for schools to manage students' information.
  • Created a communication system to distribute emails and SMS to students. Using a Windows Service written in .NET Core handled third-party integration with emails and SMS providers. Integrated legacy back-end web services to this service.
  • Migrated the main Windows Forms app from .NET 3.5 to .NET 4.6.
  • Moved development from a VS2008 environment using .NET 3.5 to VS2019 .NET 4.6.
Technologies: Windows Services, Windows Forms (WinForms), Web Services, IIS, .NET, Azure, APIs, Microservices, HTTPS, Visual Basic .NET (VB.NET), VB.NET, Active Server Pages (ASP), Azure SQL, ASP.NET

Senior Software Developer

2015 - 2019
Knowtion SA de CV
  • Supported a large WPF application with the MVVM pattern.
  • Wrote a centralized-data solution to handle patient information from different hospitals.
  • Developed an auditing system for securing data using MongoDB.
  • Migrated the database to Microsoft SQL Azure database and designed implementation to migrate current back-end to Azure web apps.
  • Led the development team and handled recruitment activities and evaluations for the development team.
  • Implemented the usage of reactive programming in the WPF application.
  • Audited the code for best practices and handled code review activities.
Technologies: MongoDB, Microsoft SQL Server, Git, Ruby, Jenkins, Windows Communication Foundation (WCF), Windows Presentation Foundation (WPF), C#, JavaScript, HTML, IIS SQL Server, SOAP, Azure, Microsoft Power BI, APIs, HTTPS, Python, Visual Basic .NET (VB.NET), VB.NET, .NET, Active Server Pages (ASP), Azure SQL, ASP.NET

Senior Software Developer

2014 - 2016
Clinical Champion
  • Built the front-end of an app from scratch with WPF and MVVM.
  • Implemented an automatic solution that updates, backups, and restores for the MongoDB database with AWS S3.
  • Updated and the supported implementation of a back-end for a new functionality.
  • Implemented a new workflow design in WPF enabling the users to completely rewrite the components used and their order.
  • Installed the automatic update solution for front-end app.
Technologies: Amazon S3 (AWS S3), MongoDB, Windows Communication Foundation (WCF), Windows Presentation Foundation (WPF), C#, Azure, APIs, HTTPS, .NET, Active Server Pages (ASP)

Senior Software Developer

2010 - 2014
  • Completely wrote from scratch an extensible WPF implementation for a client's app.
  • Built a continuous distribution system to keep apps updated following a strict distribution setting.
  • Managed and developed a warehouse management system for an automated and manual warehouse.
  • Worked as an R&D analyst for supply chain management activities in a pharmaceutical goods distribution chain.
  • Instructed other members of the development team on best practices and design policies.
Technologies: Microsoft SQL Server, Windows Communication Foundation (WCF), Windows Presentation Foundation (WPF), C#, APIs, Python, Visual Basic .NET (VB.NET), VB.NET, .NET, Active Server Pages (ASP), Microsoft Access

Software Developer

2008 - 2009
  • Built the front-end of a Java Swing application to handle payroll information.
  • Linked the application with input information from fingerprint readers to manage the employees' arrivals and departures.
  • Designed a back-end solution that was integrated with PostgreSQL.
  • Spearheaded a new visual design for legacy applications.
  • Supported new installations and troubleshot situations with clients.
Technologies: Fingerprint Readers, PostgreSQL, Java


This is a WPF app with WCF services with the Microsoft SQL Server and MongoDB. It is used by doctors, nurses, and administration personnel in several hospitals to handle patients' information and scheduling. It uses RabbitMQ as a message-queuing service to move data from one hospital to another and to a centralized database. We've implemented a CI/CD system with Jenkins which takes code from our GitHub repositories and builds, runs tests, and creates a deliverable product for our end-users.


This a type of operation management software for nurses with a WPF client. The screenshots can be seen in the second example on

Smart Pharma

A WPF app with MVVM, WCF Services, the Entity Framework, and Microsoft SQL Server to handle a drugstore's inventory, accounts, sales, and communication with other systems.

It handles the data synchronization involving over 500 locations and places that information into a centralized system. It provides continuous delivery with a specialized software that updates different locations based on roles within the hierarchy.


A WPF head-up display hook for PokerStars and Full Tilt Poker.

Autotrack GPS
A web solution with a Java back end and a PHP front end to track vehicle locations, geofencing, and emergency assistance. It uses a GPS mounted on each vehicle to send data to the system and receive instructions from it through TCP or UDP connections. The user could control the vehicle top-speed, allowed locations, usage schedules among others. It enables a user to follow a fleet of vehicles 24/7 and query their previous locations.
2011 - 2014

Bachelor's Degree in Computer Science

Universidad Rafael Belloso Chacin - Maracaibo, Venezuela

2004 - 2009

Bachelor's Degree in Modern Languages

Universidad del Zulia - Maracaibo, Venezuela

2003 - 2009

Technical Degree in Computer Science

Colegio Universitario Dr Rafael Belloso Chacin - Maracaibo, Venezuela


International English Language Testing System (C2)

British Council


Programming in C# Specialist



Microsoft Certified Professional



Diplôme d'études en langue française (B2)



Windows Forms (WinForms), REST APIs, AutoMapper, Facebook Messenger API


Visual Studio, Visual Studio Tools for Office (VSTO), Microsoft Visual Studio, RabbitMQ, Jenkins, Microsoft Access, Git, Microsoft Power BI


Windows Presentation Foundation (WPF), Entity, .NET Core, Entity Framework Core, .NET, ASP.NET, ASP.NET Core, ASP.NET Core 2, ASP.NET Core MVC, Azure Bot Framework


C#, Visual Basic 6 (VB6), Visual Basic .NET (VB.NET), XAML, VB.NET, Java, SQL, HTML, JavaScript, Active Server Pages (ASP), Python, PHP, Ruby


Model View ViewModel (MVVM), Microservices


Microsoft, Windows Desktop, Linux, Azure, Amazon Web Services (AWS), Visual Studio Code (VS Code), Raspberry Pi, Microsoft Bot Framework, Messenger Bots


Databases, Azure SQL, Microsoft SQL Server, MongoDB, MySQL, PostgreSQL, Google Cloud, SQL Server Reporting Services (SSRS), IIS SQL Server, Amazon S3 (AWS S3)


Web Development, Windows Communication Foundation (WCF), HTTP REST, APIs, IT Infrastructure, SOAP, HTTPS, Fingerprint Readers, IIS, Web Services, Windows Services, MVC Development, Geolocation, Messenger, French-English Translation

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