Marcos Antonio de Assis

Re-engaged by TripArc after a previous engagement via BairesDev (2021-2023); Built REST APIs and gateway applications integrating external car rental and travel service providers; Migrated features from monolithic applications to Azure-based microservices and REST APIs, analyzing existing functionality to define how each feature should be rebuilt; Used Azure Pipelines for CI/CD and took part in deployments to UAT and Production; Worked with Azure SQL Database and MongoDB, Azure Service Bus as a message broker, Azure Feature Management (feature flags), Azure Key Vault, Azure Blob Storage for log storage, and Azure Application Gateway; Wrote unit and integration tests with xUnit and worked with the QA team on testing procedures; documented APIs with Swagger (OpenAPI) and Scalar; Worked on ASP.NET MVC applications alongside new REST APIs and microservices; Delivered full-stack features, developing the Angular front end in TypeScript and fixing issues across back end and front end; Applied AI-assisted development practices with Claude Code to speed up implementation, code review, bug fixing, documentation, and understanding a large legacy codebase

Worked as a backend developer building new integration services to exchange data between SAP and internal applications; Implemented REST APIs documented with Swagger and SOAP Web Services

Maintained and modernized full-stack C# applications built on .NET Framework, .NET Core, and ASP.NET MVC (Razor) with SQL Server, implementing new features and fixing issues across the back end and front end; Improved application performance by 45% by refactoring legacy code and applying design patterns; Extracted parking reservation and payment processing from the main application into Azure Functions, improving the main application’s performance; Implemented new SQL Server stored procedures, fixed existing ones, and built REST APIs documented with Swagger; Built front-end features with JavaScript, jQuery, HTML, CSS, and Kendo UI (Telerik); Troubleshot application issues across multiple layers (application and Azure infrastructure)

Modernized a monolithic .NET application into microservices using CQRS, cutting deployment time by about 60% with CI/CD pipelines in Azure DevOps; Participated directly in microservices definition and architectural decisions, guiding other developers; Increased automated test coverage from 0% to 85% with unit and integration tests; Implemented messaging with NServiceBus and Azure Service Bus; used Azure Blob Storage, Azure Key Vault, and Azure Kubernetes Service; Integrated multiple payment providers in a Payment Gateways project; Developed shared frameworks, libraries, and reusable components in C# (.NET 5) with SQL Server and MongoDB; Responsible for code reviews, providing technical guidance and feedback to ensure code quality and maintainability

Development of REST APIs to deal with enormous quantities of information in systems for the Public Ministry and the Brazilian Supreme Court, using .NET Core, ASP.NET Core, Kubernetes, and AWS; Analysis of complex technical issues in the microservices or APIs; Responsible for reviewing code from other developers and helping other team members; Coding, with C# as the primary language, on four types of database engines: Oracle, DB2, PostgreSQL, and MS SQL Server; Use of tools such as Visual Studio 2019, JetBrains Rider, Gitlab, IBM RTC, RabbitMQ; Worked on application performance improvements as well as SQL queries.

Outsourced to Objective Solutions on a project for a public transportation company from New York, USA; Built several kinds of applications using .NET and .NET Core (REST API, Windows Services, Windows Forms), C# as language, and using database engines such as MS SQL Server, MySQL, SQLite, Entity Framework, and ADO.NET; Worked on a small project and developed a .NET Core REST API to run on Windows and Ubuntu Server; Use of tools like Bitbucket, Jira, Gitkraken, Fork, RabbitMQ, Postman, and Visual Studio as main IDE; Dealt with a huge amount of socket messages between vehicles and the monitoring system; Improved existing systems and fixed issues on said systems; Provided technical leadership to teammates and responsible for several code reviews;

Migrated legacy applications created in Delphi to .NET Core and ASP.NET Core, using C# as language, databases such as MS SQL Server, as well as MySQL, Dapper, and Entity Framework; Use of tools such as Gitlab, Hangfire, Postman, Insomnia, and Visual Studio as primary IDE; Created REST APIs to provide information to CRM systems like Oracle Sales Cloud; Developed integration between Oracle Sales Cloud, Oracle RightNow, and IBM Mainframes; Created ETL tools to collect copious amounts of data from several sources and concentrate it in a data warehouse for analysis; Responsible for the definition of the APIs, as well as the best way to provide information to several areas and systems; Provided technical leadership to teammates;

Acted as a technical leader on a migration project from legacy Delphi applications to REST API applications, using .NET Framework, ASP.NET Web API, C# as language, and PostgreSQL as the primary database engine; Used tools like VSTS, Postman, and Visual Studio as primary IDE; Provided technical leadership to other team members; Responsible for code reviews and some scrum ceremonies;

Hoplon is a Brazilian game company creating games for PC, Xbox, and PlayStation; Worked as a Data Engineer, developing ETL tools to collect and process raw data from log files generated by its game in addition to comments regarding said games on social networks; Dealt with an enormous amount of data extracted from log files; Responsible for developing new ETL tools, as well as the improvement of legacy tools, using .NET Framework, C# as the language, MySQL and MS SQL Server as database engine; Use of tools such as VSTS and Visual Studio as primary IDE; Responsible for the organization and availability of all data collected and processed; Provided information to Data Scientists, Studio Managers, and Game Designers; Responsible for some code reviews; Interaction with other developer teams (back-end services, web pages, game developers) to support tackling specific issues in the game.

Development of integration with Brazilian tax systems, mainly with electronic invoices (NFe/NFSe); Bug fixing in different applications; The main technologies used at this job were .NET/C#, Delphi 2010, Firebird SQL, MS SQL Server

Worked as a researcher in the innovation area, where I was responsible for the evaluation of new technologies and tools that were used in the evolution of the company's applications; Development of new products utilizing the .NET Framework 4.5 (C#), Entity Framework 6, NHibernate 4, Microsoft SQL Server, and MySQL as database servers, along with Team Foundation Server 2013 as the code management tool; Development of Single-Page Applications (SPAs) with AngularJS on the frontend and ASP.NET Web API on the backend; Utilization of Dependency Injection frameworks, such as Castle Windsor, Ninject, and Unity; Projects created using security standards (authentication and authorization) based on the OAuth 2.0 specification.

I worked at the Justice Unit, developing integration between the first- and second-level systems, making corrections and improvements to these systems, as well as the integration routines between them; These solutions have been and are currently used in most of the national territory by the Courts of Justice and Public Ministries, with thousands of users; The main tools used in addition to Delphi were Microsoft SQL Server databases, Oracle, and DB2, as well as Team Foundation Server for code control and versioning, and Code Collaborator for code revisions and agile methodologies, specifically SAFe (Scaled Agile Framework), which encompasses several agile methodologies tailored for large organizations; Some development techniques, such as Clean Code and Unit Tests, were also employed in the coding process.

Improvement of applications developed mainly in Delphi 5, 7, 2006, 2010, as these applications are destined to branches of diverse activities like Retail (ERP), Human Resources (Payroll), and large governmental legal systems.

Collaboration on the development of automation systems for commercial and industrial enterprises (ERP) using Object-Oriented Programming (OOP) with the Pascal language and the .NET Framework 4.0, along with MS SQL Server and Firebird SQL, utilizing NHibernate and Entity Framework Code First. Development of integrations between Win32 applications, Team Foundation Server, and Microsoft Dynamics CRM 2011 Online with .NET 4.0 (C#); Creation of several WCF Services and Windows Services to provide communication between new and legacy systems; Development of applications to integrate our ERP system with the government's tax system, specifically the Brazilian Electronic Invoice (NFe) and NFSe; Utilization of Design Patterns, Test-Driven Development (TDD), and Domain-Driven Design (DDD). Collaborating with the .NET architectural team to develop new products and enhance existing ones through refactoring and applying good software development practices.

I worked as a senior developer, with my primary responsibility being the initial implementation of a web-based legal system. All required components for that application were implemented using Flagship (a xBase/Clipper dialect), and the data access providers also used Flagship and ANSI C All applications, libraries, and data providers were required to run on Linux, including Red Hat, RHEL, SUSE, OpenSUSE, Fedora, and other Linux distributions. The primary target of this application was insurance and banking companies, such as Itaú, Unibanco, Mapfre, and Louis Dreyfus Commodities, as well as small, medium, and large law firms across the country.

Worked on administrative systems implementation using Clipper 5.2 and Clipper 5.3. Management of local network and local servers (Windows NT 4), backup servers, and user training.