Full Stack Engineer (TDD / C# / JavaScript) We are hiring a Full Stack Software Engineer with a strong test-driven development (TDD) background to help build the next generation of a mission-critical cybersecurity and communications platform used globally.This is a hands-on role focused on designing and delivering partner API integrations across a complex security ecosystem - including endpoint protection, network security, user awareness tooling, and monitoring systems.You''ll work as part of a collaborative product team alongside full stack and front-end developers, supported by QA and DevOps, reporting into engineering leadership. Why This Role Matters The next-generation platform will provide customers with a unified view of security across distributed environments. As integrations expand, maintaining a high bar for quality, reliability, and test coverage is critical.This role will also play a key part in strengthening TDD practices across the team - leading through code and delivery. What You''ll Do Design and build API integrations across a cybersecurity-focused product stackDeliver clean, maintainable full stack solutions using .NET and modern JavaScript frameworksLead by example in test-driven development practicesIntegrate third-party systems using REST APIs, OAuth2, webhooks, and resilient patternsContribute to a scalable, observable integration layerCollaborate with Product, QA, and DevOps to deliver high-quality releasesUse AI-assisted development tools as part of