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Foresite, a mission-driven cybersecurity and SecOps platform, is seeking a Senior Fullstack Engineer to architect and scale their multi-tenant SaaS platform. As a foundational engineering team member, you will lead the evolution of the front-end ecosystem while maintaining strong backend capabilities, ensuring the platform remains performant, accessible, and maintainable as it scales.
You will architect and build front-end features using React.js and TypeScript, work across the full stack owning backend integrations and data access patterns end-to-end, and build/maintain a shared component library. You'll partner closely with product, design, and backend engineers to ship production-ready features, integrate with PostgreSQL and NoSQL data stores through clean backend service layers, and design/consume RESTful APIs powering core workflows.
Key responsibilities include championing code quality through thorough reviews, owning deployments and production health, driving architectural decisions, mentoring junior and mid-level engineers, identifying performance bottlenecks, applying security-conscious development practices (auth, RBAC, data isolation in multi-tenant contexts), and engaging actively in Agile ceremonies. You'll document your work and contribute to a knowledge-sharing culture.
Foresite operates as a Google Cloud Premier SecOps Partner on a modern tech stack including React 19, TypeScript, Tailwind CSS, PostgreSQL, Drizzle ORM, and GCP. The company emphasizes shipping safely and frequently using stacked PR workflows, comprehensive test suites (Vitest/Playwright), and robust CI/CD pipelines. You'll work on impactful projects involving AI, automation, and scalable data access patterns protecting global enterprises from cyber threats.
The organization is described as "humans-first," respecting technical depth and treating developer well-being as a priority. Foresite provides pre-approved vendor and technical training at company expense, supportive peer code reviews, and deep technical mentorship.
REQUIREMENTS:
- 5+ years of professional experience in Full Stack development with clear specialization in front-end architecture for complex B2B SaaS or Cybersecurity platforms
- Deep proficiency in React 18/19 and TypeScript
- Comfortable with React Router v7 and modern routing patterns
- Strong web security knowledge: understand and mitigate XSS, CSRF, injection attacks in modern React/TypeScript contexts
- Comfortable designing schemas, writing queries, and reasoning about performance across PostgreSQL and Firestore
- Experience with modern ORMs and runtime validation for data integrity
- Experience with multi-tenant architectures and implementing RBAC/ABAC models for strict data isolation
- Write tests as standard practice; proficient with Vitest, Testing Library (unit/integration), and Playwright (E2E)
- Comfortable with CI/CD pipelines, Git, and modern workflows (e.g., Stacked PRs)
- Embrace AI-assisted development tools
- Comfortable on both sides of system boundaries: consuming third-party APIs on frontend and writing backend glue; understand API contracts, webhook reliability, data consistency
NICE TO HAVE:
- Background in Cybersecurity with understanding of unique UI/UX and security challenges
- "Security First" approach to coding with OWASP Top 10 knowledge
