Senior Developer (Windows), Product Security

Security and data privacy are at the core of everything 1Password does. The Product Security team implements new security features across the macOS, iOS, Android, Windows, Linux, and Web applications, builds libraries to share common security-critical code, resolves vulnerabilities, and promotes secure coding practices across the organization. As a Senior Developer on the Device Security squad, you will implement the next generation of security features in 1Password's applications and help shape security operations and best practices, with a focus on the Windows platform. You'll guide product teams on secure coding, resolve security vulnerabilities when they arise, and demonstrate leadership in secure development.

Responsibilities

• Work within a small team of developers who are specialists in Rust, Go, Swift, and security development.
• Implement new security features for the next generation of 1Password and develop secure libraries that share common security-critical code across applications.
• Assist in security design efforts and scoping initiatives for new features by identifying major tasks and breaking down, estimating, and planning work.
• Act as a trusted point of contact for management and other developers on secure development.
• Code, test, debug, deliver, and maintain production software for new and existing product features.
• Collaborate with teams across the hybrid core architecture, from Design to QA, plus security engineering for design guidance and secure coding practices.
• Mentor junior and new team members through technical guidance, knowledge sharing, and pair programming.
• Review code to maintain high quality and support a safe environment for giving and receiving feedback.

Qualifications

• 4+ years of software development experience with a security angle, including modern encryption techniques and libraries or authentication protocols.
• 4+ years of hands-on Windows security development with expertise in languages such as Rust, C#, C/C++, Go, or TypeScript.
• Experience with Rust development and creating FFI interfaces, especially for Windows, plus knowledge of Windows OS architecture and platform-specific optimization.
• Familiarity with TPM and HSM functionality and proven experience with Windows security features such as Windows Hello, BitLocker, Secure Boot, and Credential Guard.
• Strong understanding of the security domain: cryptography, network security, application security, common threat vectors, and access control mechanisms.
• Knowledge of and practical experience with agentic AI model capabilities and workflows.
• Bonus: SAML, OAuth, and OpenID Connect experience, SaaS product experience, and familiarity with CI/CD pipelines and tools like DataDog, SemGrep, or Sonarqube.