Lead Software Engineer, Client Systems

About the Position

... create world-changing products using God-given talents . ..

Our company is a fast-growing, profitable SaaS company providing best-in-class encrypted email and file sharing for organizations that handle sensitive data. We’ve been named a Best Place to Work three years in a row and recognized by PC Magazine as the best encrypted email and file-sharing platform for five consecutive years.

We’re seeking a hands-on Lead Software Engineer, Client Systems, to build and evolve software that runs on customer endpoints and securely coordinates with our cloud services. This is not a traditional web frontend or backend API-only role. The work spans local state, file-system integration, networking, synchronization, identity, reliability, and secure protocols across Windows and macOS, with supporting web and cloud services.

Strong candidates may come from desktop applications, endpoint security, embedded or device-to-cloud systems, file synchronization, collaboration software, developer tools, or other technically complex client environments. We value strong computer science fundamentals and experience solving difficult production problems more than experience with any specific programming language.

Responsibilities

• Own the architecture and implementation of software running on customer endpoints and its communication with our cloud services.
• Design reliable synchronization and state-management systems across clients, devices, and backend infrastructure, including offline behavior, retries, event ordering, conflict resolution, and recovery from partial failures.
• Build software that interacts with local storage, file systems, networking, authentication, access controls, and operating-system services.
• Design and evolve secure protocols and interfaces across client and cloud components.
• Ensure the security and reliability of our applications through secure coding techniques and thoughtful system design.
• Diagnose and resolve complex issues involving performance, scalability, connectivity, and reliability.
• Collaborate with engineering, product, design, infrastructure, and security teams throughout feature development.
• Guide and mentor junior and mid-level engineers through code reviews, design reviews, and hands-on technical leadership.
• This is a hands-on individual-contributor leadership role with no direct reports or formal performance-management responsibilities. You will lead through architecture, technical judgment, project ownership, design reviews, code reviews, and mentorship while remaining actively involved in implementation.

Requirements

• BS or MS in Computer Science or a related field, or equivalent practical experience.
• Strong computer science fundamentals, including data structures, algorithms, concurrency, networking, and systems design.
• Substantial experience building commercial software that runs on a client, endpoint, desktop application, embedded device, or similar distributed environment.
• Experience shipping production software used by external customers and supporting it through performance, reliability, and failure scenarios.
• Experience designing distributed systems involving synchronization, consistency, event delivery, retries, fault tolerance, or multi-device coordination.
• Demonstrated ownership of complex technical initiatives from architecture and design through implementation and production operation.
• Ability to lead technical projects, influence architectural direction, and mentor other engineers while remaining hands-on.
• Proficiency in at least one production programming language. No specific language is required.

Nice to Have

• Experience building native or cross-platform applications for Windows, macOS, Linux, embedded devices, or endpoint environments.
• Experience working with local storage, file systems, access controls, sockets, network protocols, or operating-system services.
• Understanding of cryptographic fundamentals, including public-key encryption, symmetric encryption, and digital signatures.
• Experience with secure identity and authentication systems such as PKI, WebAuthn, SSO, SAML, OIDC, SCIM, Active Directory, or role-based access control.
• Experience with file synchronization, offline-first systems, replication, consistency models, conflict resolution, or multi-device state management.
• Experience building security, privacy, collaboration, endpoint, or other reliability-sensitive products.

We Offer

• The opportunity to solve meaningful problems that improve privacy and security for everyone.
• Competitive salary and equity package.
• Health and dental insurance.
• A team of highly motivated, mission-driven professionals.

About the Company

Our company currently uses Python and Go across core services, C++ for portions of the Windows client, Swift and native tooling on macOS, web technologies for browser-based clients, and SQL/SQLite for relational and local storage. Direct experience with these technologies is helpful but not required.