Mid-Level I Senior.Net I AWS Developer, Brazil

About the role

At Ci&T, you will partner with the largest financial institution in Brazil to architect and deliver high-impact digital solutions powered by AI and advanced cloud technologies. You will own the full lifecycle of complex software projects, translating business demands into robust, scalable, and secure .NET applications deployed on AWS. Your work will directly influence the evolution of the company's technology platform and the quality of its services to millions of users. You will collaborate daily with cross-functional, multidisciplinary teams, shaping technical decisions and mentoring peers to elevate the collective standard of engineering. Expect to work in an environment that values agility, data-driven decisions, and continuous improvement through DevOps and Lean practices. You will leverage event-driven architectures and modern design patterns to solve challenging problems in real time. This role is critical for driving innovation and ensuring that technology becomes a true strategic asset for the business.

Key facts

What you'll do

Architect and develop high-performance, scalable .NET solutions aligned with business objectives and technical best practices.

Design and implement microservices using Clean Architecture, Domain-Driven Design, and SOLID principles to ensure maintainability and flexibility.

Integrate applications with AWS services such as EC2, ECS, EKS, Fargate, S3, SQS, SNS, Lambda, and API Gateway to build resilient and distributed systems.

Model and expose RESTful APIs, applying API Gateway strategies and feature toggle mechanisms to manage releases in production safely.

Implement secure authentication and authorization flows, applying OWASP guidelines and security best practices to protect applications and data.

Develop and maintain automated test suites using xUnit, incorporating mocks and unit testing strategies to ensure code quality and reliability.

Work with messaging platforms such as Amazon SQS, Kafka, or RabbitMQ to enable asynchronous communication and event-driven solutions.

Optimize database interactions using Dapper and Entity Framework, working with both relational and NoSQL stores to meet performance and scalability needs.

Define and manage CI/CD pipelines with GitHub Actions or AWS CodePipeline, promoting fast and reliable software delivery.

Apply Infrastructure as Code using Terraform or AWS CloudFormation to automate environment provisioning and governance.

Monitor application behavior and infrastructure health through tools like Splunk, Grafana, AppDynamics, or AWS X-Ray.

Experiment with deployment strategies such as Canary, Blue/Green, and A/B testing to reduce risk and improve release confidence.

Support the evolution of existing systems through refactoring, code improvements, and adherence to engineering standards.

Collaborate with analysts, product owners, and other stakeholders to refine requirements and align technical solutions with business goals.

Requirements

You must possess and demonstrate the following hard skills and experiences as mandatory criteria for this role.

Expert knowledge of object-oriented programming and proficiency with C# and ASP.NET Core for building robust and testable applications.

Strong experience with dependency injection patterns in .NET and practical use of ORM tools such as Dapper and Entity Framework.

Solid understanding of microservices architecture, Clean Architecture, Domain-Driven Design, and SOLID principles.

Familiarity with event-driven architecture, including the differences between Saga Choreography and Saga Orchestration.

Ability to implement feature toggle strategies in production environments to enable controlled feature releases and rollbacks.

Experience designing and consuming RESTful APIs, including the use of API Gateway services on AWS.

Sound knowledge of application security concepts, including authentication, authorization, and OWASP top threats.

Hands-on practice with unit testing using xUnit and strategies for mocking dependencies to ensure code correctness.

Proven experience with AWS services, including compute (EC2, ECS, EKS, Fargate), storage (S3), messaging (SQS, SNS), serverless (Lambda), and monitoring (CloudWatch).

Working knowledge of messaging systems such as Amazon SQS, Kafka, or RabbitMQ for asynchronous integration.

Experience with relational and NoSQL databases, including data modeling and performance tuning.

Comfort with containerization using Docker and orchestration with Kubernetes for deploying and managing applications.

Proficiency in Infrastructure as Code tools such as Terraform or AWS CloudFormation to manage cloud resources.

Understanding of CI/CD concepts and hands-on experience with Git for version control and collaborative workflows.

Nice to have

Experience with monitoring and observability tools such as Splunk, Grafana, AppDynamics, or AWS X-Ray.

Knowledge of deployment strategies like Canary, Blue/Green, and A/B testing to improve release safety.

Familiarity with GitHub Actions or AWS CodePipeline to automate build and delivery workflows.

Experience with feature toggle frameworks in production scenarios.

Practical notes

This is a home office position based in Brazil. Professionals residing in the Metropolitan Region of Campinas may be required to attend the company's offices according to the current attendance policy. The selection process will follow the standard Ci&T procedures, and the schedule is expected to align with business hours. Travel requirements are not applicable for this role. Visa sponsorship may be considered depending on legal and operational needs.