Freelance Linux Kernel Development Jobs in Texas

Secure platform ownership for next-generation Hardware Security Modules 

Position Summary 

We are seeking a Senior Embedded Linux Platform Engineer to lead the development and maintenance of the embedded software platform powering our next-generation Hardware Security Modules (HSMs). This role bridges hardware and application software by owning the Linux platform, Board Support Package (BSP), security architecture, and hardware interfaces that enable our cryptographic applications. 

The ideal candidate has deep experience with embedded Linux, Buildroot, kernel and device-tree configuration, low-level hardware interfaces, secure boot, PCIe, and high-speed networking. The engineer will collaborate closely with hardware, FPGA, security, manufacturing, and application teams to deliver a secure, reliable, production-ready appliance. 

Responsibilities 

Embedded Linux Platform 

• Develop, maintain, and reproducibly build a Buildroot-based Linux distribution. 

• Customize and maintain Linux kernels for selected System-on-Modules (SoMs). 

• Configure and maintain device trees and board-specific platform definitions. 

• Build and maintain BSPs for custom HSM hardware and successive board revisions. 

• Integrate kernel drivers, platform services, bootloaders, and root filesystems. 

• Optimize boot performance, system footprint, reliability, and maintainability. 

• Support production images, manufacturing configuration, and secure update mechanisms. 

Hardware Integration 

• Bring platform hardware into Linux and expose clean, documented interfaces to application software. 

• Integrate and validate IC, SPI, GPIO, UART, USB, PCIe, EEPROM/flash, and other board-level interfaces. 

• Enable sensors, fan controllers, LEDs, buttons, watchdogs, voltage monitors, reset controls, TPMs, and secure elements. 

• Develop or adapt kernel drivers and user-space services where existing interfaces are insufficient. 

• Use schematics, datasheets, oscilloscopes, logic analyzers, and other tools to diagnose board-level issues. 

Security 

• Design, implement, maintain, and validate secure boot and the complete chain of trust. 

• Configure and integrate hardware roots of trust, TPMs, secure elements, and measured-boot capabilities where appropriate. 

• Recommend secure component choices and platform architectures based on threat, lifecycle, and supply-chain considerations. 

• Review hardware and low-level software designs for security weaknesses and attack surface. 

• Support tamper detection, encrypted storage, key protection, secure manufacturing, and device provisioning. 

• Define and support secure firmware and software update strategies, including rollback protection and recovery. 

Networking 

• Integrate and support 10 GbE connectivity through PCIe-connected network devices and external Ethernet interfaces. 

• Configure Ethernet controllers, PHYs, drivers, link behavior, and relevant hardware offload features. 

• Tune the Linux networking stack for throughput, latency, reliability, and predictable appliance behavior. 

• Diagnose performance bottlenecks across PCIe, DMA, interrupts, drivers, and the network stack. 

Platform Enablement 

• Lead bring-up of new SoMs, custom boards, and hardware revisions from first power-on through application readiness. 

• Create platform diagnostics, hardware validation utilities, and manufacturing test support. 

• Establish automated, repeatable build and integration workflows for embedded platform releases. 

• Support production, quality, field engineering, and sustaining activities throughout the product lifecycle. 

• Document platform architecture, interfaces, security assumptions, build procedures, and operational constraints. 

Requirements

Required Qualifications 

• Bachelor's or Master's degree in Computer Engineering, Electrical Engineering, Computer Science, or a related field, or equivalent practical experience. 

• Five or more years of professional experience developing embedded Linux systems. 

• Strong C programming and debugging skills in resource-constrained or hardware-adjacent environments. 

• Hands-on experience with Buildroot or Yocto, Linux kernel configuration, device trees, and cross-compilation toolchains. 

• Practical knowledge of the Linux boot process, bootloaders such as U-Boot, root filesystems, kernel modules, and driver integration. 

• Experience collaborating across hardware, systems, security, and application engineering disciplines. 

• Proficiency with Git and disciplined software configuration-management practices. 

Required Technical Experience 

Embedded Linux 

• Buildroot or Yocto; Linux kernel configuration and customization; device trees; bootloaders; init systems; root filesystems; kernel modules; BSP and driver integration. 

Hardware Interfaces 

• Hands-on experience with several of the following: IC, SPI, UART, GPIO, PCIe, USB, MDIO, Ethernet PHYs, DMA, and interrupts. 

Networking 

• Linux networking stack, Ethernet drivers, 10 GbE, PCIe-connected networking, and network performance analysis or tuning. 

Platform Security 

• Experience with one or more of the following: secure boot, measured boot, TPMs, secure elements, trusted execution, hardware roots of trust, secure updates, or applied cryptography fundamentals. 

Preferred Qualifications 

• Experience developing security appliances, HSMs, cryptographic products, or other high-assurance embedded systems. 

• Familiarity with FIPS 140-3, Common Criteria, or comparable product-security certification environments. 

• ARM64 platform experience and familiarity with SoMs from NXP, AMD, Intel, TI, or similar vendors. 

• Linux kernel or PCIe driver development experience. 

• Experience reviewing schematics and conducting hands-on hardware debugging. 

• Experience with manufacturing diagnostics, secure provisioning, lifecycle controls, and field-update strategies. 

Nice to Have 

• OpenSSL, PKCS #11, secure key storage, or related cryptographic interfaces. 

• Trusted Firmware-A, OP-TEE, trusted execution environments, or hardware-backed attestation. 

• Rust for systems programming. 

• CI/CD practices for embedded systems and reproducible, containerized build environments. 

• Experience with performance profiling, reliability testing, or fault-injection techniques. 

What Success Looks Like 

• New hardware platforms boot reliably and can be brought to application readiness through a repeatable, documented process. 

• All required peripherals and control signals are exposed through stable, well-documented Linux interfaces. 

• Secure boot and the platform root of trust are implemented, validated, maintainable, and aligned with product-security goals. 

• 10 GbE and external Ethernet interfaces achieve expected throughput, latency, and reliability. 

• Builds are reproducible, version-controlled, automated, and suitable for manufacturing and field release. 

• Platform risks are identified early, communicated clearly, and addressed in partnership with hardware and security teams. 

• The embedded platform provides a stable, secure foundation that allows HSM application teams to deliver confidently. 

Benefits

• Health, dental, vision, life, and short/long-term disability insurance
• Paid vacation, holidays, and sick leave
• Competitive compensation and opportunities for advancement
• Retirement plan with employer contribution match
• Welcoming, family-style corporate culture uniquely suited to fast-paced, entrepreneurial, and motivated individuals
• One of San Antonio's "Best Places to Work" for nine consecutive years