Rafael Chei

Staff Software Engineer
Oakland, FL [email protected] chei.dev

Experienced Staff Software Engineer with 20+ years of experience in designing, developing, and scaling applications in cloud and mobile environments. Extensive experience developing complex systems, improving technical workflows, and contributing to cross-functional projects. Strong background in .NET, cloud infrastructure, DevOps, and modern web/mobile technologies.

Experience

Staff Software Engineer

Genius SIS, Inc. — Remote (HQ: Plantation, FL)
  • Migrated a legacy ASP.NET application to .NET 9 Web API and React, improving performance, scalability, and code maintainability.
  • Created a Retrieval-Augmented Generation (RAG) AI application leveraging Genius product documentation to enhance information retrieval and user support.
  • Trained a custom AI model to accurately extract invoice data from PDF and image documents, improving processing automation.
Jun 2022 - Present

Senior Software Engineer

Genius SIS, Inc. — Plantation, FL
  • Developed mission-critical SIS features and APIs; integrated third-party platforms.
  • Modernized the frontend using React and TypeScript; improved UI performance and accessibility.
  • Introduced Hangfire to handle background processing, preventing web application freezes caused by data-intensive operations.
Mar 2018 - May 2022

Mobile Platform Specialist (iOS)

Banco (Digio) — São Paulo, Brazil
  • Led iOS development using Swift and Objective-C for digital banking apps with thousands of users.
  • Delivered features such as biometric login, push notifications, and secure authentication.
Sep 2016 - Mar 2018

Earlier Engineering Roles (Brazil)

Conductor, Serasa Experian, ILATI, Accentiv, Emphasys
  • Held progressive roles from intern to senior engineer building .NET and mobile apps in fintech and enterprise environments.
  • Technologies: C#, VB.NET, SQL Server, Objective-C, Swift, ASP.NET, WinForms.
2004 - 2016

Education

Universidade Presbiteriana Mackenzie

Bachelor of Computer Information Systems
Emphasis on Database
2004 - 2009

Skills

Languages & Frameworks
  • C#
  • .NET / .NET Core
  • React
  • TypeScript
  • JavaScript
  • Java
  • SQL
  • WCF / REST APIs
Cloud & DevOps
  • Microsoft Azure
  • AWS
  • Azure DevOps
  • GitHub Actions
  • Terraform
  • Docker
AI / Machine Learning
  • Retrieval-Augmented Generation (RAG)
  • Custom Model Training
Mobile Development
  • Swift
  • Objective-C
Soft Skills
  • Problem Solving
  • Continuous Learning
  • Cross-Functional & Remote Collaboration
Languages
  • English (Full Professional)
  • Portuguese (Native)
  • Spanish (Intermediate)

Certifications

  • Microsoft Certified: Azure Fundamentals - Issued Dec 2022
  • AWS Certified Cloud Practitioner - Issued Oct 2020