Software Engineer, Model Runtime

Job summary

Responsibilities

You will build the model runtime within the inference engine that executes complex, frontier models at scale on OpenAI’s custom silicon. The runtime will sit between models running on the hardware and the upper layers of the cluster serving software stack, translating demanding inference workloads…

• Design and implement the LLM inference runtime for frontier models running on custom silicon.
• Build scheduling, continuous batching, memory management, KV-cache management, and execution orchestration for high-performance inference.
• Develop distributed execution strategies across chips, hosts, and racks, including model partitioning, communication, and synchronization.
• Optimize end-to-end latency, throughput, memory efficiency, and hardware utilization across diverse model architectures and serving workloads.
• Partner with kernel, compiler, architecture, and silicon teams to co-design interfaces and remove performance bottlenecks across the stack.

Tech stack

• vLLM
• C++
• Rust
• Python