Senior Back-End - .NET, API, AI Ready

The Role Capco is seeking a Senior Full Stack Engineer with strong .NET and React experience to join our Technology & Engineering practice in Toronto. In this role, you will help design, develop, and maintain modern applications and APIs that support business-critical solutions for our clients. Working alongside experienced engineers, product teams, and quality specialists, you will contribute to the delivery of secure, scalable, and high-performing applications while leveraging AI-assisted development practices to improve efficiency and quality. Why This Role Is Open We are currently hiring for this role due to an existing or newly created vacancy within our organization. This position is open as part of our ongoing business needs, and we are actively reviewing applications to fill this role with a qualified candidate who can make an immediate impact. What You’ll Do Design, develop, and maintain scalable web applications using .NET, React, SQL Server, and modern development practices. Build secure RESTful APIs, implementing authentication and authorization mechanisms such as JWT and OAuth2 while ensuring consistent validation and error handling. Create responsive and accessible user interfaces using React and modern front-end technologies, delivering reliable user experiences. Containerize applications using Docker and contribute to CI/CD processes, code reviews, documentation, and knowledge sharing activities. Leverage AI-assisted development tools responsibly to accelerate coding, testing, debugging, and technical documentation while maintaining quality and security standards. What We’re Looking For 5+ years of professional software engineering experience with strong hands-on expertise in .NET, ASP.NET Core, and REST API development. Working proficiency in React, SQL Server, Docker, and data access technologies such as Dapper and/or Entity Framework Core. Understanding of API security concepts, including authentication and authorization patterns such as JWT and OAuth2. Experience working within established development processes, including source control, code reviews, CI/CD pipelines, and agile delivery environments. Strong collaboration, communication, problem-solving, and troubleshooting skills with the ability to work effectively within cross-functional teams. Bonus Points For Experience with Tailwind CSS and modern component libraries such as shadcn/ui. Exposure to Azure cloud environments and deployment troubleshooting activities. Familiarity with Snowflake and data platform integrations. Experience contributing to technical documentation, runbooks, and API documentation. Interest in emerging AI-assisted software engineering practices and responsible AI usage. Why Join Capco Deliver high-impact technology solutions for Tier 1 financial institutions. Work in a collaborative, flat, and entrepreneurial consulting culture. Access continuous learning, training, and industry certifications. Be part of a team shaping the future of digital financial services. Help shape the future of digital transformation across FS & Energy. Benefits Comprehensive Benefits Coverage – 100% company-paid health, life, and disability insurance effective from Day 1 of employment. Retirement Savings Program – Registered Retirement Savings Plan (RRSP) with the option of receiving a matching employer contribution. Virtual Health Care and Employee & Family Assistance Program (EFAP) available to employees and their dependents/partners. Parental Leave Top-Up, New Parent Gift, and Wellness Support including fitness reimbursement benefits. Business Coach from Day 1 with personalized one-on-one coaching to support career growth and professional development. Inclusion at Capco We’re committed to making our recruitment process accessible and straightforward for everyone. If you need any adjustments at any stage, just let us know – we’ll be happy to help. We value each person’s unique perspective and contribution. At Capco, we believe that being yourself is…