Responsibilities
- Advance inference efficiency end-to-end
- Design and prototype algorithms, architectures, and scheduling strategies for low-latency, high-throughput inference.
- Implement and maintain changes in high-performance inference engines (e.g., SGLang- or vLLM-style systems and Together’s inference stack), including kernel backends, speculative decoding (e.g., ATLAS), quantization, etc.
- Profile and optimize performance across GPU, networking, and memory layers to improve latency, throughput, and cost.
- Unify inference with RL / post-training
- Design and operate RL and post-training pipelines (e.g., RLHF, RLAIF, GRPO, DPO-style methods, reward modeling) where 90+% of the cost is inference, jointly optimizing algorithms and systems.
- Make RL and post-training workloads more efficient with inference-aware training loops—for example, async RL rollouts, speculative decoding, and other techniques that make large-scale rollout collection and evaluation cheaper.
- Use these pipelines to train, evaluate, and iterate on frontier models on top of our inference stack.
- Co-design algorithms and infrastructure so that objectives, rollout collection, and evaluation are tightly coupled to efficient inference, and quickly identify bottlenecks across the training engine, inference engine, data pipeline, and user-facing layers.
- Run ablations and scale-up experiments to understand trade-offs between model quality, latency, throughput, and cost, and feed these insights back into model, RL, and system design.
- Own critical systems at production scale
- Profile, debug, and optimize inference and post-training services under real production workloads, taking research ideas all the way to stable, measurable improvements in deployed systems.
- Drive roadmap items that require real engine modification—changing kernels, memory layouts, scheduling logic, and APIs as needed.
- Establish metrics, benchmarks, and experimentation frameworks to validate improvements rigorously.
- Provide technical leadership (Staff level)
- Set technical direction for cross-team efforts at the intersection of inference, RL, and post-training.
- Mentor other engineers and researchers on full-stack ML systems work and performance engineering.
Requirements
- 3+ years of experience working on ML systems, large-scale model training, inference, or adjacent areas (or equivalent experience via research / open source).
- Advanced degree in Computer Science, EE, or a related field, or equivalent practical experience.
- Demonstrated experience owning complex technical projects end-to-end.
Nice to Have
- Have a bias toward implementation and shipping— you are excited to modify real engines and services, not just prototype in research code.
- Have strong expertise in at least one of the following, and are excited to collaborate across (and grow into) the others:
- Systems-first profile: Large-scale inference systems (e.g., SGLang, vLLM, FasterTransformer, TensorRT, custom engines, or similar), GPU performance, distributed serving.
- RL-first profile: RL / post-training for LLMs or large models (e.g., GRPO, RLHF/RLAIF, DPO-like methods, reward modeling), and using these to train or fine-tune real models.
- Model architecture design for Transformers or other large neural nets.
- Distributed systems / high-performance computing for ML.
- Are comfortable working from algorithms to engines: Strong coding ability in Python.
- Experience profiling and optimizing performance across GPU, networking, and memory layers.
- Able to take a new sampling method, scheduler, or RL update and turn it into a production-grade implementation in the engine and/or training stack.
- Have a solid research foundation in your area(s) of depth: Track record of impactful work in ML systems, RL, or large-scale model training (papers, open-source projects, or production systems).
- Can read new RL / post-training papers, understand their implications on the stack, and design minimal, correct changes in the right layer (training engine vs. inference engine vs. data / API).
- Operate well as a full-stack problem solver: You naturally ask: “Where in the stack is this really bottlenecked?”
- You enjoy collaborating with infra, research, and product teams, and you care about both scientific quality and user-visible wins.
Additional Information
- We invite you to join a passionate group of researchers in our journey in building the next generation AI infrastructure.
