*CodSpeed is the continuous performance optimization platform trusted by world-class engineering teams. We shift performance testing left to catch regressions before they ship. From open-source projects like Mozilla, Pydantic, and Astral to enterprise teams at Cloudflare, Vercel, and beyond. CodSpeed empowers developers to measure, track, and improve software efficiency across the stack.*

We're a small, deeply technical team looking for engineers who want real ownership, direct user contact, and the chance to ship features end-to-end.

Tech stack

Systems: C/C++ · Rust · Zig

Backend: Rust

Infrastructure: AWS (IaC with CDK) · Docker · Kubernetes

Tooling: GitHub · Linear · Claude Code

What you’ll do

• Build the next generation of high-performance CPU simulation tooling to improve the performance measurement landscape
• Work with high-level language interpreter codebases (CPython, V8, …) to enhance instrumentation quality
• Build various kernel’s I/O emulations to provide robust performance metrics agnostically from the hardware
• Make core architecture choices, ship significant features to production, and shape the company culture

Requirements

• Experience in a System Programming language: C, C++, Zig or Rust
• Understanding of Unix systems and kernels
• Experience contributing to or maintaining open-source projects
• Deeply care about technical excellence

Extras

• Deep understanding of modern CPU Architectures
• Experience with Javascript and Python runtime internals and their optimization pipelines
• Experience with GPU(CUDA) programming