Principal Software Engineer

About CEF AI

CEF AI is a stealth-stage startup building foundational AI infrastructure to power the next generation of sovereign, scalable, and deeply personalized AI systems. We operate at the intersection of frontier research and applied systems design, with a focus on giving individuals and organizations full control over their data and AI agents. Our team brings together top-tier engineers, founders, and thinkers passionate about shaping a more open and equitable AI future.

About the Role

We’re hiring a Principal Software Engineer to architect, build, and scale the core systems that power our privacy-first, edge-native AI platform. This is a high-impact role for an engineer who thrives at the intersection of product vision, technical execution, and team leadership.

You’ll lead critical initiatives across backend services, SDKs, and developer platforms—driving performance, reliability, and usability across the stack. More than just a builder, you’ll be a force multiplier: mentoring engineers, influencing architectural direction, and helping define how AI-native infrastructure gets built in the real world.

Tasks

• Systems Architecture: Design, implement, and scale foundational backend systems and APIs that power decentralized, real-time AI workflows.
• Developer Experience: Own the end-to-end developer journey by building SDKs, CLIs, and interfaces that make it easy to interact with our platform.
• Cross-Stack Execution: Rapidly prototype and productize features using tools like Cursor, React, and TypeScript—without sacrificing quality or scale.
• Technical Leadership: Guide architectural decisions, lead design reviews, and mentor engineers in best practices for distributed, high-performance systems.
• Collaboration: Partner with product, design, and leadership to align technical execution with company vision and user needs.
• Execution Ownership: Drive key projects from 0→1 with autonomy, accountability, and a strong bias for action.

Requirements

• Experience: 4+ years in high-performance software environments, with a proven track record of shipping complex systems end-to-end.
• Deep Technical Expertise: Mastery of one or more systems languages (Go, Rust, Kotlin, etc.) and strong backend engineering fundamentals.
• Architectural Fluency: Experience designing and scaling distributed systems with performance, reliability, and observability in mind.
• Quality & Testing: Strong discipline around testing, CI/CD, and long-term maintainability (TDD preferred).
• Builder Mindset: Ability to turn ambiguity into architecture, and architecture into reliable, extensible code.
• Communication: Clear, concise communicator who can explain tradeoffs, write technical specs, and mentor junior engineers.
• Bonus: Experience with edge computing, Web3 protocols, real-time data infra, or AI/ML-powered systems.

Benefits

• Competitive Compensation & Meaningful Equity: We offer founder-level alignment because this is a founder-level role.
• High-Ownership Role: You’ll directly shape our technical direction and long-term stack architecture.
• Work with Top-Tier Founders & Engineers: Collaborate daily with a deeply technical, mission-driven leadership team.
• Build the Future of AI Infrastructure: We're not optimizing yesterday's workflows—we're inventing tomorrow's.
• Zero Bureaucracy, Maximum Autonomy: We stay lean, move fast, and trust you to lead.
• Remote-First, In-Person When It Counts: We're distributed across SF and Europe, with monthly hackathons and off-sites to align and build together.

Our Hiring Process

We move fast, stay transparent, and focus on real collaboration. Here’s what the process looks like:

1. Intro Call – A quick chat to align on expectations, interests, and team fit.
2. Technical Deep Dive – A focused conversation with our Engineering Manager to explore your systems thinking and past work.
3. CEO Interview – A strategic discussion around vision, mindset, and long-term alignment.
4. Reference Collection – We’ll speak with a few people you’ve worked closely with.
5. Paid Trial (~5 Days) – A short, real-world engagement so we can see how we work together , happening in parallel with offer and terms discussion.

Join CEF AI as a Principal Software Engineer to help design and deliver the future of privacy-first, agentic AI. If you want to work on original systems that will define the next decade of compute—apply now.