Principal Software Engineer_Fullstack

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Principal Software Engineer_Fullstack based in India. This is a senior individual-contributor role focused on shaping customer-facing platforms and shared engineering capabilities at scale. You will lead architecture, design, and delivery across frontend experiences, backend services, APIs, integrations, and cloud platforms. The role combines hands-on software development with technical leadership, allowing you to solve complex engineering challenges directly. A major focus will be building secure, reliable AI experiences, including assistants, agents, orchestration, and reusable platform capabilities. You will help establish modern AI-assisted engineering practices that improve delivery speed while maintaining quality, security, and human oversight. Working across product, UX, security, AI, and platform teams, you will influence technical direction and raise engineering standards. This is an opportunity to make a broad impact on scalable SaaS products in a highly collaborative, remote-first environment. Lead the architecture, design, and end-to-end delivery of customer-facing capabilities spanning web interfaces, backend services, APIs, integrations, and shared cloud platforms. Write and maintain production-quality code, develop prototypes, review architecture and code, and personally address complex technical and production challenges. Evolve reusable frontend and backend platform capabilities that enable product teams to deliver consistent, accessible, secure, and maintainable customer experiences. Define service boundaries, APIs, data contracts, integration patterns, and versioning strategies for capabilities shared across multiple products. Design and operate cloud-native, multi-tenant systems with strong requirements for scalability, availability, performance, resilience, security, and cost efficiency. Apply secure-by-design practices across authentication, authorization, role-based access, tenant isolation, privacy, auditability, and customer-data management. Build secure and consistent experiences for customers interacting with AI assistants and agents, including reusable capabilities for routing, context management, tool integration, orchestration, access control, and human oversight. Establish practical approaches to AI evaluation, guardrails, regression testing, observability, latency, cost control, and safe failure handling. Use AI coding agents throughout the software development lifecycle, including codebase exploration, design, implementation, testing, debugging, refactoring, code review, and documentation, while validating generated changes before release. Develop repeatable agentic engineering practices covering task decomposition, context management, human review, automated verification, and responsible use of AI coding tools. Translate product objectives and ambiguous technical challenges into clear architectural direction and incremental delivery plans. Mentor engineers, promote strong engineering practices, and build alignment across product, UX, security, applied AI, and platform teams. Requirements: 12+ years of professional software development experience, with current experience operating at Principal, Staff, Architect, or equivalent level. Proven hands-on experience building production-grade AI applications or agentic workflows beyond experimental prototypes. Strong proficiency with AI coding agents across design, implementation, testing, debugging, code review, and documentation. Extensive architecture and system-design experience with large-scale, customer-facing SaaS platforms. Hands-on backend development experience using Go and/or Java, combined with frontend development experience using Angular and/or React. Experience designing, deploying, and operating secure microservices and APIs on AWS. Strong understanding of scalable, cloud-native, distributed systems and moder