Senior .Net Engineer

Location: Portugal; Brazil SUMMARY: As a Senior .NET Engineer, you will play a key role in evolving and optimising our payment-related services, ensuring reliability, performance, and scalability in a high-traffic environment. You’ll work hands-on across modern .NET technologies to improve existing systems, diagnose complex issues, and design robust solutions that keep our platform running smoothly. We’re looking for engineers who are passionate about continuous learning, modern engineering practices, and building resilient, customer-focused systems. You’ll join a collaborative, supportive environment where people are encouraged to grow, experiment, and push the boundaries of technical excellence. WHAT WILL YOU BE DOING: As part of an agile software development team, you will: Design, develop, maintain, and enhance .NET microservices and backend APIs that support critical payment workflows Analyse and optimise existing applications for performance, scalability, and reliability Investigate and troubleshoot production issues, identifying root causes and delivering high-quality fixes Refactor legacy components into modern, cloud-ready services Contribute to improving engineering standards, code quality, and best practices through thoughtful code reviews Collaborate with engineers, product managers, and QA to deliver high-impact features for millions of users Mentor junior engineers, providing guidance on architecture, coding patterns, and engineering principles WHAT WE ARE LOOKING FOR: 5+ years of experience building highly scalable, customer-facing systems using modern .NET (C#, .NET 6/7/8) Strong experience developing RESTful APIs and microservices using ASP.NET Core Solid experience building and maintaining distributed services, with a focus on performance, resilience, and observability Advanced proficiency in SQL Server, including optimisation of complex queries, stored procedures, and database schema design Hands-on experience with caching technologies such as Redis Proficiency in integrating with internal and external REST APIs Experience working in event-driven or message-based architectures (Kafka, SNS/SQS, RabbitMQ – exposure is fine) Solid understanding of cloud-native development, ideally with AWS (Lambda, API Gateway, DynamoDB, SNS/SQS, ECS/EKS) Strong experience with Git-based workflows Good understanding of secure coding, authentication/authorisation patterns, and modern internet security practices Experience working in an Agile, cross-functional team Strong verbal and written communication skills in English NICE TO HAVE: Background in payment systems, PCI considerations, or high-volume transactional flows Experience with observability tools such as Grafana, Kibana, Datadog, AppDynamics, OpenTelemetry Experience with CI/CD pipelines (GitHub Actions, Jenkins, ArgoCD, Azure DevOps, GitLab CI) Experience with performance optimisation in high-traffic environments Ability to collaborate effectively with engineers, product managers, QA, and stakeholders Comfortable working both independently and as part of a distributed engineering team WHAT’S IN IT FOR YOU? Be part of our collegial environment where responsibility and authority are shared equally amongst colleagues and help create our company culture. A culture in which we don’t criticise failure but ensure we learn from our mistakes An Agile environment where your ideas are welcome The possibility to grow and experience different projects Ongoing Training & Mentoring The possibility of travelling