William B. Dos Santos, Developer in São Paulo - State of São Paulo, Brazil
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William B. Dos Santos

Verified Expert  in Engineering

C# Developer

Location
São Paulo - State of São Paulo, Brazil
Toptal Member Since
February 21, 2024

William has over 17 years of professional experience in diversified roles. He has contributed to projects that generated million-dollar revenues, showcasing a keen strategic sense. He has experience fixing bugs and working with various technologies, including .NET. With experience optimizing system processes' performance and achieving improvements of up to 60-fold in operational efficiency through troubleshooting and strategic enhancements, William is looking forward to his next challenge!

Portfolio

F1RST Technology
C#, .NET, PL/SQL, Java, TypeScript
Qintess
C#, .NET, PL/SQL, Java, TypeScript, Financial Markets
Inetx
C#, .NET, Microsoft SQL Server, Infragistics, JavaScript

Experience

Availability

Part-time

Preferred Environment

C#, Complex Problem Solving, Agile, Code Review, SQL, Redis, Object-relational Mapping (ORM), Version Control, Git, Projects

The most amazing...

...project I've contributed to is for F1RST Technology, where I worked on integrations with 3rd-party systems, streamlining inter-system communication.

Work Experience

Senior Software Engineer

2020 - PRESENT
F1RST Technology
  • Played a pivotal role in projects that delivered multi-million-dollar profits.
  • Propelled process efficiency over 10 times, increasing two transactions per second (TPS) to 20.
  • Provided technical mentorship to junior team members, fostering skill development and team cohesion.
  • Collaborated and integrated with 3rd-party systems, streamlining inter-system communication.
Technologies: C#, .NET, PL/SQL, Java, TypeScript

Senior Software Engineer

2019 - 2020
Qintess
  • Started working on a big project and played a pivotal role in projects that delivered multi-million-dollar profits.
  • Joined the company after the project's successful implementation.
  • Propelled process efficiency over 10 times, showing an unwavering commitment to operational excellence.
  • Communicated and integrated with 3rd-party systems, streamlining inter-system communication.
Technologies: C#, .NET, PL/SQL, Java, TypeScript, Financial Markets

Senior Software Engineer

2018 - 2019
Inetx
  • Pioneered and delivered a project in the financial sector. Managed end-to-end implementation, including business logic, front end, back end, databases, and authentication and authorization systems.
  • Created an advanced reporting system that offers multidimensional insights, elevating operational transparency and decision-making processes.
  • Managed testing processes and seamlessly integrated communication with 3rd-party tools to ensure project robustness.
  • Offered my expertise to Sinqia, where I tackled challenges within their internet banking for individuals and Software Business Systems (SBS), actively contributing to resolving complex issues.
Technologies: C#, .NET, Microsoft SQL Server, Infragistics, JavaScript

Senior Software Engineer

2017 - 2018
Grupo SHC
  • Contributed to system projects for vehicle delivery, including supervising purchases, sales, and workshop processes.
  • Evolved a comprehensive project and excelled in back-end processes, improving the data flow.
  • Simplified data exchange with SAP, including visualization and help in advanced business application programming (ABAP) code.
  • Developed simple-to-use front-end pages and improved reporting features for better decisions.
  • Updated the market information capture system, improving reports.
  • Adopted innovative technology stacks for adaptable report formatting, including AngularJS and MongoDB.
Technologies: C#, .NET, MVC Design, SAP, MongoDB

Senior Software Developer

2012 - 2017
Valor Econômico
  • Engaged deeply in C# back-end processes within the ValorPro system.
  • Managed the capturing, processing, and storage of millions of data points in databases from various global stock exchanges.
  • Used the Advanced Message Queuing Protocol (AMQP) Protocol to ensure seamless system integration.
  • Employed C++ with the Financial Information eXchange (FIX) protocol for retrieving and processing data from many international stock exchanges.
  • Created and supplied ongoing support for a robust CI/CD system using Team Foundation Server (TFS) Build and TFS Release Management.
Technologies: C#, .NET, CI/CD Pipelines, C, C++, FIX Protocol

Senior Software Developer

2010 - 2012
Grupo SHC
  • Played a key role in the inception of the vehicle delivery system project, overseeing purchase, sale, and workshop processes.
  • Created and evolved a comprehensive project and excelled in back-end processes, improving the data flow.
  • Simplified data exchange with SAP, including visualization and help in ABAP code.
  • Developed simple-to-use front-end pages and improved reporting features for better decisions.
Technologies: C#, .NET, Web Forms, NHibernate, SAP Integration

Software Developer

2009 - 2010
Spring Wireless
  • Fixed reported bugs in mobile, web, desktop, and business intelligence projects for customers in Brazil, Europe, and Central and South America.
  • Enhanced the system process performance by 10 times.
  • Corrected bugs and optimized the system for mobile devices using Java.
Technologies: C#, .NET, Web Forms, Java, SQL Server Analysis Services (SSAS), SQL Server Reporting Services (SSRS)

Software Developer

2006 - 2009
7COMm
  • Acted as the developer and provided support in the Cisfarma project, working with web, desktop, and mobile.
  • Created reports using ASP and ASP.NET technologies.
  • Built Component Object Model+ (COM+) components with Visual Basic 6 to process transmitted file contents.
Technologies: C#, .NET, ASP.NET Web Forms, Visual Basic 6 (VB6), COM+, C++

Valor PRO

https://valorpro.globo.com/#/
I contributed to Valor PRO.

With behind-the-scenes market news, analytical tools, and complete information about finance and business, Valor PRO is a real-time information service, which is an idle speed through the market to the replacement of Valor Econômico.
2022 - 2023

Postgraduate Degree in Distributed Software Architecture and Information Technology

Pontifical Catholic University of Minas Gerais - Belo Horizonte, Minas Gerais, Brazil

2004 - 2009

Bachelor's Degree in Systems Analysis and Information Technology

Fatec Ourinhos - Ourinhos, São Paulo, Brazil

OCTOBER 2023 - OCTOBER 2025

Oracle Cloud Infrastructure 2023 Certified Foundations Associate

Oracle

AUGUST 2023 - AUGUST 2026

AWS Certified Cloud Practitioner

Amazon Web Services

NOVEMBER 2022 - PRESENT

Microsoft Certified: Azure Fundamentals

Microsoft

Libraries/APIs

Node.js, Infragistics

Tools

Git

Languages

C#, SQL, Java, TypeScript, JavaScript, C, C++, Visual Basic 6 (VB6)

Storage

Databases, Redis, SQL Server 2016, Oracle Cloud, PL/SQL, Microsoft SQL Server, MongoDB, Web Forms, SQL Server Analysis Services (SSAS), SQL Server Reporting Services (SSRS)

Paradigms

Agile, Object-relational Mapping (ORM), DevSecOps, MVC Design, COM+

Platforms

Azure, Amazon Web Services (AWS)

Frameworks

.NET, NHibernate, ASP.NET Web Forms

Other

Complex Problem Solving, Version Control, Projects, Back-end, APIs, Computer Science, Analysis, Code Review, Front-end, Cloud, Networks, Financial Markets, SAP, CI/CD Pipelines, FIX Protocol, SAP Integration

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