Senior C# / .NET Developer

CI&T

Backend Developer at CI&T focusing on APIs and services for a leading Brazilian retailer. Responsible for backend solutions with a strong emphasis on security and integration.

Posted 4/17/2026full-time🇧🇷 BrazilSeniorWebsite

Tech Stack

Tools & technologies

MongoDB.NETPostgres

About the role

Key responsibilities & impact

Develop and evolve backend services and APIs with a focus on quality, security, and scalability.
Design and maintain RESTful APIs consistently and in accordance with best practices.
Work on system integrations, messaging, and asynchronous processing.
Work with relational and non-relational databases, ensuring performance and data integrity.
Apply clean code principles, design patterns, and architectural best practices in backend solutions.
Implement and maintain authentication and authorization mechanisms, including OAuth 2.0, JWT, and related standards.
Use productivity tools and development acceleration resources such as Copilot and AI agent frameworks.

Requirements

What you’ll need

Strong experience in C# and backend development with .NET 9/10.
Experience building and maintaining RESTful APIs.
Knowledge of messaging systems and asynchronous processing.
Experience with databases such as PostgreSQL and MongoDB.
Knowledge of design patterns and clean code best practices.
Experience with Copilot and AI agent frameworks.
Experience with authentication systems such as OAuth 2.0, JWT, and similar technologies.
Ability to operate in distributed environments with an architectural perspective and a focus on software quality.

Benefits

Comp & perks

Health and dental insurance
Meal and food allowance
Childcare assistance
Extended parental leave
Partnerships with gyms and health & wellness professionals via Wellhub (Gympass) TotalPass
Profit Sharing (PLR)
Life insurance
Continuous learning platform (CI&T University)
Employee discount club
Free online platform dedicated to physical and mental health and well-being
Pregnancy and responsible parenthood course
Partnerships with online course platforms
Language learning platform
And many more

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills & Tools

C#.NET 9.NET 10RESTful APIsPostgreSQLMongoDBOAuth 2.0JWTclean code principlesdesign patterns

Soft Skills

quality focussecurity focusscalability focusarchitectural perspectiveinterpersonal skills