Senior .NET Developer, Colombia

At CI&T, we help large enterprises transform the potential of AI into real business impact with AI Deployment, AI-native execution, and tech-integrated business solutions.With 30 years of experience in technological transformation, we accelerate innovation with expertise in Agentic SDLC, Application modernization, Data & AI, Martech and Business strategy.We are 8,000 CI&Ters across more than 25 countries, collaborating to build solutions with real impact. AI is already part of how we work, evolve, and innovate every day.We are looking for a Senior .NET Engineer to join our team and drive the development and integration of complex back-end software solutions. You will work closely with a multicultural team distributed across Brazil, Colombia, the UK, and the USA, collaborating daily in English and contributing to robust, scalable services and integrations.Must-Have Skills:.NET Experience: strong experience with .NET Framework and .NET Core in production systemsBackend Development: hands-on experience building back-end services with C#, ADO.NET, and SQL ServerAPIs & Integration: solid experience implementing and evolving SOAP and RESTful services, including versioning and best practicesData & Persistence: strong understanding of ADO.NET, SQL Server, database design and performance tuningXML: proficiency in XML serialization/deserializationSoftware Design: solid grasp of software design patterns and engineering best practicesTesting & Reliability: experience with unit and integration testing, troubleshooting and root-cause analysis for service reliabilityCommunication: effective communication skills in multicultural, fast-paced environmentsLanguage: advanced English proficiency (all communication in English).Key ResponsibilitiesDesign, build and maintain back-end services using C#, ADO.NET and SQL ServerImplement and evolve SOAP and REST APIs, ensuring proper versioning, security and best-practice standardsEnsure service reliability through unit and integration tests, troubleshooting, monitoring and root-cause analysisCollaborate on integration between multiple systems and services, applying appropriate software design patternsConduct code reviews, provide technical feedback and mentor junior engineersStay current with emerging technologies and industry trends, applying them to improve existing solutionsContribute to CI/CD workflows and best practices to increase development efficiency and deployment qualitySoft SkillsOwnership & Continuous Improvement: proactive in taking responsibility for tasks and driving improvementsCommunication: able to clearly explain complex technical topics to both technical and non-technical audiencesCollaboration: team player who values shared success and cross-functional collaborationAdaptability: comfortable navigating ambiguity and shifting requirements in a dynamic environmentNice-to-Have SkillsCloud: experience with cloud platforms, preferably Microsoft AzureModern Practices: familiarity with specification-driven development and agentic approaches to software developmentAgile: exposure to Agile methodologies (Scrum, Kanban, etc.)The successful candidate will deliver reliable, performant back-end services and integrations, help elevate engineering standards through reviews and mentorship, and collaborate smoothly across time zones and cultures using English as the primary language.If you are a seasoned back-end developer ready for complex challenges in a dynamic, multicultural environment, we invite you to apply and become part of our diverse team!Our benefits include: - Premium Healthcare- Meal voucher- Maternity and Parental leaves- Mobile services subsidy- Sick pay-Life insurance- CI&T University - Colombian Holidays- Paid VacationsAnd many others. Collaboration is our superpower, diversity unites us, and excellence is our standard. We value diverse identities and life experiences, fostering a diverse, inclusive, and safe work environment. We encourage applications from diverse and underrepresented groups to our job positions.