Senior Principal Software Engineer

Role overview A long-standing infrastructure software vendor is hiring a senior principal engineer for its load-balancing and application delivery platform. This is a hands-on individual contributor role with sustained technical leadership across critical subsystems. The focus is the long-term evolution, performance, security, and maintainability of a Linux-based networking product used in demanding production environments.

Responsibilities - Own engineering for critical functional and architectural areas of the load-balancing platform - Design, implement, and deliver core features and platform components in C - Serve as the technical authority for complex subsystems and lead deep problem analysis across the stack - Drive performance, scalability, and security improvements in networking-heavy code paths - Lead proofs of concept and prototypes to validate designs and de-risk architectural choices - Mentor senior engineers and contribute to cross-team standards, tooling, and automation

Requirements - Extensive experience delivering complex, high-performance Linux systems - Expert-level C systems programming with a focus on low-latency TCP/IP networking - Deep knowledge of Linux internals, including the networking stack, memory management, and kernel/userspace interactions - Proven performance engineering skills in profiling, bottleneck analysis, and optimization - Strong security background spanning threat modeling, cryptography, and secure design - Solid grasp of CPU, memory, NUMA, and I/O characteristics for performance work

Nice to have - Expertise in authentication, web application firewalls, load balancing, proxy architectures, and TLS - Experience with embedded Linux and hardware acceleration - Background in distributed systems across cloud or virtualized environments - Observability practices across complex, distributed systems

Benefits and work setup - Generous compensation package with an employee stock purchase plan - 25 vacation days annually, plus a birthday day off and community service time off - Pension plan, group life assurance, income protection, and private health insurance - Hybrid working model with a cycle-to-work scheme