Senior Full Stack Engineer – Architecture Team

About RethinkFirst Rethink is on a mission to inspire hope and power potential. Founded in 2008 and headquartered in NYC, Rethink First is a pioneer and market leader in behavioral and mental health technology. Developed by nationally recognized experts in the field, Rethink’s award-winning online solutions feature comprehensive video-based training and education programs and sophisticated behavior intervention planning tools. Our offerings include individualized assessments, online skills-based activities, access to remote clinician-led consultations, and more. The Rethink platform is used by Fortune 500 companies, school districts, government agencies, public and private behavioral health providers, and families caring for individuals with developmental disabilities worldwide. Position Overview We are seeking a Senior Full Stack Engineer to join our Architecture Team. This role is ideal for an experienced engineer who thrives at the intersection of hands-on coding and strategic architecture. You will help shape technical direction, champion best practices, mentor other developers, and ensure our systems are scalable, secure, and reliable. This position requires deep expertise in Microsoft technologies (C#, .NET, SQL, Azure), strong knowledge of modern software design, and the ability to translate business needs into effective technical solutions. Responsibilities - Contribute to architectural design, ensuring alignment with scalability, performance, security, and compliance standards. - Develop, design, test, and deploy cloud-based applications using C#, .NET Core, SQL, Azure, and Angular. - Establish and enforce coding standards, design patterns (SOLID, DDD, CQRS, etc.), and development methodologies (Agile, CI/CD, DevOps). - Write, review, and maintain high-quality code with strong emphasis on unit testing (XUnit/NUnit), integration testing, and automated pipelines. - Mentor and coach engineers across teams, promoting continuous learning and knowledge sharing. - Collaborate with cross-functional stakeholders to translate requirements into technical designs and solutions. - Drive adoption of best practices in DevOps, microservices, containerization (Docker), messaging (Service Bus), caching (Redis), and observability (App Insights, logging, monitoring). - Participate in architectural reviews, code reviews, and design discussions. - Contribute to long-term platform strategy, modernization, and cloud migration initiatives. - Troubleshoot production issues and guide root cause analysis to ensure system reliability. Qualifications - Education/Experience • Bachelor’s degree in Computer Science, Engineering, or related field (or equivalent experience). • 8+ years of professional software development experience, with at least 3+ years in a senior or lead role. • Proven experience designing and implementing enterprise-scale applications on the Microsoft stack (C#, .NET Core/Framework, SQL Server, Azure). Technical Skills • Strong expertise in object-oriented design, design patterns, SOLID principles, and domain-driven design. • Experience with Angular, TypeScript, HTML, CSS, JavaScript. • Strong SQL skills including query optimization, schema design, and stored procedures. • Cloud-native development in Microsoft Azure: App Services, Functions, Service Bus, Storage, Key Vault, Azure SQL, and monitoring tools. • Familiarity with microservices architecture, RESTful APIs, and event-driven systems. • Hands-on experience with CI/CD pipelines, Azure DevOps, Git, Docker, and Infrastructure as Code (Terraform/ARM). • Experience implementing unit testing frameworks (XUnit, NUnit, Moq), automated testing, and test-driven development (TDD/BDD). • Knowledge of healthcare domain standards (HIPAA, HITRUST, SOC2) is a strong plus. Soft Skills • Demonstrated ability to mentor and grow engineering talent, fostering collaboration and knowledge sharing. • Excellent problem-solving, communicati