Software Engineer, Sandboxing

Job summary

Responsibilities

Every time Claude runs code, uses a computer, or works as an agent, it does so inside a sandbox. Our Sandboxing team builds the isolation layer behind that work. The same systems run the code Claude writes for users, the environments we train and evaluate models in, and the agents our customers…

• Design, build, and operate the sandboxing infrastructure that runs untrusted, model-generated code and agent workloads at scale
• Improve sandbox startup time, density, and throughput, including snapshot and restore, checkpointing, and warm pools
• Strengthen isolation across compute, filesystem, and network, including egress controls and per-session credential handling
• Investigate and fix performance, reliability, and security issues at the kernel, hypervisor, and container runtime level
• Build the monitoring, tracing, and debugging tools that show where time and resources go inside a sandbox

What they're looking for

• Software engineering experience in Linux systems programming, kernel development, or another low-level area
• Strong programming skills in at least one systems language such as Rust, C, C++, or Go
• Working knowledge of virtualization or container isolation technologies such as KVM, QEMU, Firecracker, gVisor, or runc
• Understanding of Linux resource management, including namespaces, cgroups, scheduling, and memory management
• Experience profiling and debugging performance issues at the system level

Tech stack

• Rust
• C++
• Kubernetes
• AWS
• GCP