Member of Technical Staff - Security Engineering

Job Title

Member of Technical Staff — Security Engineering

Role Summary

Design and implement security across the control chain for devices, boards, chassis, and rack controllers, spanning bare metal, RTOS, and embedded Linux. You will translate threat models into concrete mechanisms (secure boot, key hierarchies, attestation, secure channels, firmware update protections) and work closely with architecture, hardware and software teams to validate and deploy them.

Role is hybrid (London or Bristol). Candidates should be eligible for any export-control checks required for this work.

Experience Level

Mid-level (Level - Mid-Career). The posting does not state explicit years-of-experience guidance.

Responsibilities

The role focuses on designing, prototyping, and validating system-level security across devices and racks.

• Define threat models, trust boundaries, and a secure-by-design approach across controllers and devices.
• Design and implement secure boot, root of trust, verified/measured boot, signing/verification and anti-rollback.
• Secure interconnects and communication channels with authentication and integrity protections.
• Design cryptographic primitives: key hierarchies, provisioning, secure storage, device identity, and remote attestation.
• Implement end-to-end firmware update safety: signed images, rollback protection, staged rollout and recovery paths.
• Harden runtime systems: host Linux kernel and on-die firmware protections, triage vulnerabilities and drive fixes to closure.
• Collaborate with hardware, firmware and software teams to integrate security into product development and first bring-up.

Requirements

We expect practical, hands-on experience securing real systems. Below are must-have and desirable qualifications.

• Must-have: Adversarial mindset and clear threat-modeling instincts (trust boundaries, assets, residual risk).
• Must-have: Hands-on experience with secure-boot chains, root of trust, cryptography and key management, and where these mechanisms fail in practice.
• Must-have: Experience designing secure protocols and channels between components.
• Must-have: Strong systems programming in C and Rust, with an emphasis on memory safety and defensive coding.
• Must-have: Experience building security mechanisms (secure-boot, key hierarchies, attestation flows) and integrating them across firmware and OS.
• Nice-to-have: Familiarity with attestation and management-plane standards (DICE, RATS, SPDM, MCTP, PLDM), HSM/TPM/secure-element/Caliptra, and firmware/open-boot projects.
• Nice-to-have: Background in assurance, supply-chain security (SBOM, SLSA), fuzzing/testing, NIST/Common Criteria or physical/side-channel awareness.
• Nice-to-have: Experience with AI/LLM-assisted security tooling, and RISC-V, GPU or ML-accelerator platforms.

Education Requirements

Not specified.

About the Company

Company: Fractile

Headquarters: London, UK

Fractile is on a mission to revolutionize AI by developing silicon, systems, and software that enable the fastest execution of advanced models at lower costs. Established in 2022, the company has rapidly expanded, fostering a collaborative culture in its London and Bristol offices. With a focus on innovation in ML/AI IC product development, Fractile combines hardware and software to deliver high-impact solutions for data center applications.