Browser Security Engineer

About the role

We’re hiring a Browser Security Engineer to harden and extend our Chromium-based browser runtime. You’ll work at the intersection of sandboxing, networking, and virtualization - ensuring our browsers run securely and efficiently across thousands of concurrent users.

What you’ll do

Debug, patch, and optimize Chromium builds running inside Kernel’s microVM environments.

• Implement and maintain network isolation, proxy routing, and IP handling for browsers.
• Collaborate with infra engineers on unikernel-based isolation, process scheduling, and kernel security policies.
• Build internal tooling for binary analysis, crash triage, and vulnerability monitoring.
• Support the team in maintaining secure supply chain and reproducible builds for our browser images.

What we’re looking for

• Deep familiarity with Chromium internals, browser sandboxes, or renderer/network stacks.
• Experience with Linux kernel, microVMs (Firecracker, Cloud-Hypervisor, Kata, gVisor, etc.), or container isolation.
• Strong debugging skills with strace, gdb, perf, or similar low-level tools.
• Knowledge of networking fundamentals (DNS, TCP/IP, NAT, proxies, TLS).
• Background in security engineering or browser hardening a plus.

What you can expect as a Kernel

• Industry-competitive salary
• Above market equity
• Premium medical + dental coverage + dependent coverage
• Small, trusting team of senior + staff engineers
• Default async with minimal bureaucracy
• Daily lunches on us
• Unlimited PTO
• 401k + company match
• Relocation assistance

Hiring process

We have a simple process focused on real world collaboration and jointly getting to know each other:

• 30 minute intro calls with one of Kernel’s co-founders
• 45-minute technical interview (virtual)
• Half-day on-site (in-person) working with our team on relevant technical challenges.
• Offer!