Software Engineer, Systems (AI)

TL;DR

Software Engineer, Systems (AI): Developing and optimizing the performance and reliability of Claude Code and the Bun JavaScript runtime with an accent on low-level systems programming and runtime internals. Focus on reducing latency, memory usage, and startup time through the optimization of syscalls, allocators, and kernel interfaces.

Location: Hybrid; must be based in or be able to work from the San Francisco or New York City offices (at least 25% attendance required)

Salary: $320,000 - $485,000 USD

Company

hirify.global is a public benefit corporation focused on creating reliable, interpretable, and steerable AI systems.

What you will do

• Design and optimize core systems inside Bun and Claude Code, including runtime internals, I/O paths, and memory management.
• Drive down memory usage, latency, and startup time across the agent execution loop and Bun runtime.
• Profile and fix performance bottlenecks from kernel interfaces up through the JS engine to the agent layer.
• Collaborate with researchers and product engineers to ensure model capabilities provide a fast developer experience.
• Contribute to the Bun runtime and toolkit that underpins various Labs products and the Agent SDK.

Requirements

• 5+ years of professional work experience.
• Strong expertise in C and/or C++ and Rust (Zig is a plus).
• Deep systems programming experience with Linux internals, syscalls, and I/O (kqueue, epoll, io_uring).
• Experience with language runtimes, virtual machines, compilers, or JS engines (e.g., JavaScriptCore, SpiderMonkey).
• Must be located in or able to work from San Francisco or New York City.

Culture & Benefits

• Competitive compensation with annual salary and equity matching.
• Generous vacation and parental leave.
• Flexible working hours and collaborative office spaces.
• Visa sponsorship availability.
• Commitment to diverse perspectives and inclusive hiring practices.