Research Engineer - Inference

About the Position

Research Engineer - Inference

Join Prime Intellect as a Research Engineer - Inference to build the open superintelligence stack and improve rollout throughput for long-horizon agents.

Role Impact

Build the inference systems that power Prime Intellect’s RL research, scaling toward 1–3T parameter models on NVL72 clusters. Your work will improve rollout throughput and make frequent model updates practical.

Responsibilities

• Extend prime-rl’s vLLM integration to bring new model architectures into RL training, with small-scale validation before larger runs.
• Improve rollout throughput for long-horizon agents, tuning concurrency and KV-cache reuse as context lengths grow.
• Optimize multi-node MoE inference, including expert parallelism and the tradeoffs of separating prefill from decode.
• Reduce trainer-to-inference weight-update overhead through sharding-aware transfer and communication overlap, while keeping rollout workers on the intended policy version.
• Build on FP8 and evaluate lower precision. Use trainer/sampler mismatch checks to catch numerical regressions and measure the effect on RL training.
• Work with model researchers on architecture choices that improve inference efficiency, balancing model quality against execution cost on the target hardware.

Requirements

• Experience building or optimizing GPU inference systems, with an understanding of inference-engine internals.
• Strong Python skills and experience with PyTorch or a comparable ML framework.
• Ability to profile end-to-end workloads and turn measurements into verified performance improvements.
• Experience debugging numerical or integration issues in ML systems.

Nice to Have

• Contributions to vLLM or another inference engine.
• CUDA or Triton kernel work, particularly for low-precision inference.

We Offer

• Cash Compensation Range: $150-350k, including equity incentives, aligning your success with the growth and impact of Prime Intellect.
• Flexible Work Arrangements: Option to work remotely or in-person at our offices in San Francisco.
• Visa Sponsorship and Relocation Assistance: For international candidates.
• Quarterly Team Off-sites, Hackathons, Conferences, and Learning Opportunities.
• Opportunity to Work with a Talented Team: United by a shared passion for leveraging technology to accelerate science and AI.

About the Company

Prime Intellect is building the open superintelligence stack: the infrastructure frontier AI labs build internally, made available to every ambitious AI team. Our platform, Lab, unifies compute, environments, evaluations, secure sandboxes, high-performance training, and deployment into one full-stack system for post-training at frontier scale - from SFT and RL to tool use, agent workflows, and continuously improving production models.

Prime Intellect has raised $150M in total funding from Founders Fund, Radical Ventures, NVIDIA, and exceptional AI, infrastructure, and enterprise operators, including Andrej Karpathy, Dwarkesh Patel, and leaders and founders from Ramp, Perplexity, Harvey, Mercor, Zapier, Datadog, Cognition, OpenAI, Thinking Machines, Together AI, SemiAnalysis, LangChain, Browserbase, Cloudflare, Sierra, Databricks, Airbnb, OpenRouter, Standard Intelligence, Fleet, Core Auto, and more. We are looking for people who want to build at the intersection of frontier research, real infrastructure, and go-to-market for a category that does not fully exist yet.