Performance Engineer, Inference EngineNew$350K

The opportunity

Anthropic's inference engine is the software between the accelerator kernels and the routing layer. It manages the entire token path in between: batching requests, laying the model out across chips, managing memory for weights and activations, coordinating every forward pass, and managing model state across requests.

What you'll do

  • Keep device utilization high. Accelerators should never be waiting due to other overheads.

  • Reuse instead of recompute. Keep model state cached and reuse it whenever: that is cheaper than computing it again.

  • Measure, model, then change. We build the observability to see where the gaps: are, model the impact of potential improvements, deploy them, and go around again, with Claude speeding up every turn of that loop.

  • Tokens you can trust. Ensuring model quality matters more than efficiency. We: build the infrastructure to ensure Claude maintains its intelligence across platforms and over time.

  • Safety on every token. We work closely with our safeguards and safety teams.: The inference engine is the backbone behind our production safety systems, ensuring efficiency without compromising robustness.

  • A working mental model of LLM inference: how prefill and decode land on an accelerator's compute, memory, and interconnect, and what the host is doing meanwhile

What they're looking for

  • Experience inside an LLM serving engine and a sense of where its abstractions strain
  • GPU/Accelerator programming
  • Language modeling with transformers
  • Experience building an allocator, cache, scheduler, or high-bandwidth transport
  • Fluency in Rust
  • Experience making systems reproducible: determinism, replay, property-based tests