Development | Senior Back-End Developer (.NET)

Description

Job Summary: We are seeking a Senior Back-End Developer with expertise in C# and .NET to work in a fintech environment, leading architectural decisions and ensuring delivery excellence. Key Highlights: 1. Lead complex projects and architectural decisions technically. 2. Apply Clean Architecture, Hexagonal Architecture, and DDD for modularity and scalability. 3. Implement asynchronous communication, messaging, and event-driven architecture. **The Mission** **** We are looking for a **Senior Back\-End Developer** to work in a highly scalable, secure, and data-oriented environment — typical of fintechs and financial platforms that demand robustness, resilience, and advanced observability. We seek someone with deep expertise in **C\# and .NET**, strong experience in distributed systems, event-oriented architecture, and modern engineering practices. You will serve as the team’s technical reference, leading architectural decisions and ensuring delivery excellence. If you have solid experience with **DDD, SOLID, Clean Code**, microservices, messaging, events, automated testing, CI/CD, and resilience patterns such as **Circuit Breaker**, this opportunity is perfect for you. **Responsibilities and Duties** **Your challenge will be** * Lead complex projects technically, supporting architectural decisions and mentoring junior and mid-level developers. * Conduct in-depth code reviews, ensuring high standards of quality, security, and efficiency. * Propose and implement structural improvements in architecture, performance, and resilience. * Apply Clean Architecture, Hexagonal Architecture, and DDD to ensure modularity and scalability. * Develop and maintain robust, scalable, microservice-oriented APIs. * Implement asynchronous communication, messaging, and event-driven architecture (Kafka, RabbitMQ, EventHub). * Apply resilience patterns such as Circuit Breaker, Retry, Timeout, and Bulkhead to ensure availability under failure scenarios. * Build comprehensive CI/CD pipelines focused on automation, testing, governance, and security. * Work on monitoring, telemetry, and observability using tools like Datadog, Prometheus, Grafana, and OpenTelemetry. * Apply AI to development, including Cursor IDE, GitHub Copilot, and intelligent automations to boost productivity. * Model and tune SQL and NoSQL databases, analyzing performance and integrity. * Collaborate with Product, Architecture, DevOps, Cloud, and Security teams on strategic decision-making. **Requirements and Qualifications** **First and foremost, you must align with our purpose: valuing people so each can build their own story.** **In addition, it is desirable that you have** * Proficiency in C\# and .NET. * Practical expertise in DDD, SOLID, and Clean Code. * Experience with Clean Architecture and Hexagonal Architecture. * Hands-on experience with microservices, messaging, and distributed events. * Advanced knowledge of resilience patterns: * Circuit Breaker (Polly or equivalent) * Retry * Timeout * Fallback * Bulkhead * Experience with unit, automated, mock, integration, and contract testing. * Advanced CI/CD with automation pipelines (Azure DevOps, GitHub Actions, GitLab CI, etc.). * Solid knowledge of containers and orchestration (Docker, Kubernetes). * Monitoring, structured logging, and observability with Datadog, Prometheus, OpenTelemetry. * Experience with generative AI tools for development (Cursor, Copilot, ChatGPT). * Cloud (AWS or Azure) — intermediate or higher level. * Database modeling and tuning for SQL and NoSQL. * Advanced version control (Git, GitFlow or trunk\-based development). **Nice-to-Haves** * Experience with event-driven architectures and Event Sourcing. * Experience with Feature Flags, Canary Deployments, and Blue/Green deployments. * Advanced knowledge of telemetry and distributed tracing. * Open\-source contributions or active participation in developer communities. * Experience in regulated environments (PCI, LGPD, ISO). * Complementary experience with Python. **Additional Information** Here at DM, we offer the “Nosso Jeito de Cuidar” program, which consolidates all our benefits and enhances quality of life for everyone who works here. **Take a look at what you’ll enjoy as part of our team** * CAJU Flexible Benefit Card — Meal/Voucher, Transportation, and more; * Health Insurance (Bradesco); * Dental Insurance (Bradesco); * Life Insurance; * Educational incentive programs; * English Course — English Pass (partnership available to all DM employees); * Wellhub for fitness; * DM VISA Card with pre\-approved credit limit; * Birthday leave — A gift from DM to you! * PPR (Profit Sharing Program); * For parents: Daycare allowance for children up to 6 years old; * For parents: Extended maternity and paternity leave — 6 months for mothers and 20 days for fathers. **You’ll also find:** * An incredible, relaxed, and welcoming environment; * Development opportunities and room to grow your career! **WANT TO SIMPLIFY AND DEMOCRATIZE ACCESS TO CREDIT FOR THOUSANDS OF PEOPLE? LET’S DO THIS TOGETHER!** We are a financial products company founded in 2002 to **simplify and democratize access to credit**, especially for lower-income populations — our primary target audience and the group for whom we develop our solutions. We have established ourselves in the market as the **largest independent manager of private-label (store) cards**, having issued over 17 million cards. With presence across more than 13,000 points of sale nationwide and over 1,000 active partners, DM also offers personal loans, the DM App for card and digital account management, microcredit, and other services. We operate from two offices located in São José dos Campos/SP and Fortaleza/CE, and today we proudly count **over 1,200 stories**, collectively shaping a company that never stops growing! **Join us too!** \*To ensure your application is considered, please complete your registration fully and don’t forget to take the personality assessment\*