We are tech transformation specialists, uniting human expertise with AI to create scalable tech solutions.

With over 8,000 CI&Ters around the world, we’ve built partnerships with more than 1,000 clients during our 30 years of history. Artificial Intelligence is our reality.

We’re looking for a Senior . NET Developer to maintain and evolve a set of web . NET applications, with a strong focus on modernizing authentication/authorization flows and migrating to newer . NET Core versions. The frontend is built with React.

Responsibilities:
Maintain and improve existing https://dotnet.microsoft.com/en-us/apps/aspnet

/ . NET Core web apps with a React frontend.
Redesign and implement modern authN/authZ (e.g. OAuth2/OIDC, JWT, identity providers).
Plan and execute . NET Core upgrades.
Work with AWS, MySQL, PostgreSQL, and multiple external integrations.
Use Bitbucket, CI/CD, and Playwright tests as part of the delivery workflow.
Collaborate with stakeholders to discuss and prioritize tasks and clarify requirements (in English).

Requirements:
5+ years of experience with . NET (C#) and web development.
Proven experience with auth flows and . NET version migrations.
Experience with React in production environments.
Experience with AWS, relational databases, and integrations with third-party APIs.
Comfortable with Bitbucket/Git and automated testing (Playwright is a plus).
Fluent English and strong communication/relationship skills.

Our benefits:

-Health and dental insurance

-Meal and food allowance

-Childcare assistance

-Extended paternity leave

-Partnership with gyms and health and wellness professionals via Wellhub (Gympass) TotalPass;

-Profit Sharing and Results Participation (PLR);

-Life insurance

-Continuous learning platform (CI&T University);

-Discount club

-Free online platform dedicated to physical, mental, and overall well-being

-Pregnancy and responsible parenting course

-Partnerships with online learning platforms

-Language learning platform

And many more!

More details about our benefits here: https://ciandt.com/br/pt-br/carreiras

At CI&T, inclusion starts at the first contact. If you are a person with a disability, it is important to present your assessment during the selection process. See which data needs to be included in the report by clicking here . This way, we can ensure the support and accommodations that you deserve. If you do not yet have the assessment, don’t worry: we can support you in obtaining it

We have a dedicated Health and Well-being team, inclusion specialists, and affinity groups who will be with you at every stage. Count on us to make this journey side by side.