Senior Fullstack Engineer (React.js &.Net)

We’re looking for a Full Stack Developer to join our team, with a strong emphasis on frontend development using React and TypeScript. In this role, you’ll primarily focus on building high-quality user interfaces while also contributing to backend services built with .NET/C# when needed. We value engineers who enjoy solving complex problems, take ownership of their work, and dive deep into understanding the business domain.

You should be comfortable designing scalable service contracts, working with clean and maintainable data structures, and collaborating across teams. Responsibilities:

Develop and maintain modern, scalable frontend applications using React + TypeScript

Collaborate on backend services and APIs using .NET / C#

Design and consume RESTful APIs

Ensure code quality through testing, code reviews, and best practices

Contribute to architectural decisions and technical improvements

Work closely with cross-functional teams in an Agile environment Requirements: English:

Avanced or Fluent English comunication skills Languages

Strong proficiency in JavaScript / TypeScript (ES6+)

Working knowledge of C#

Solid experience with HTML, CSS, and SCSS Frontend

React (v18+), including functional components and hooks

State management with Redux / Redux Toolkit

UI frameworks such as Bootstrap / React-Bootstrap

Experience with AG Grid or similar enterprise-grade data grids

Testing with Jest and React Testing Library

Familiarity with Webpack or similar build tools Backend

Experience with .NET 8 / ASP.NET Core Web API

Strong understanding of RESTful API design

Experience with MongoDB or other NoSQL databases Tools & Practices

Proficiency with Git (branching, merging, code reviews)

Experience with CI/CD pipelines (e.g., GitLab CI/CD)

Familiarity with Agile/Scrum methodologies Nice to have:

Experience with Redux Saga or similar middleware

End-to-end testing using Playwright

Knowledge of MediatR / CQRS patterns

Validation frameworks like FluentValidation

Authentication/authorization with Auth0, OAuth 2.0, or JWT

Experience with Redis or distributed caching

Exposure to Kubernetes / Helm

Infrastructure as Code (e.g., Terraform)

Cloud experience with AWS (e.g., Lambdas, Secrets Manager)

Observability tools like Datadog

Real-time communication using SignalR

Object mapping tools like Mapster or AutoMapper Avenue Code reinforces its commitment to privacy and to all the principles guaranteed by the most accurate global data protection laws, such as GDPR, LGPD, CCPA and CPRA. The Candidate data shared with Avenue Code will be kept confidential and will not be transmitted to disinterested third parties, nor will it be used for purposes other than the application for open positions. As a Consultancy company, Avenue Code may share your information with its clients and other Companies from the CompassUol Group to which Avenue Code’s consultants are allocated to perform its services.