Founding AI Research Engineer

Plexus is working with a well-funded, early-stage AI infrastructure company seeking a Founding AI Research Engineer to help build and scale next-generation AI systems from the ground up.   The company is rapidly expanding its AI capabilities across compute, storage, and distributed infrastructure, and this is the most strategic hire on the roadmap right now. The AI team is lean and technical, reporting directly to the CTO, and this person will be treated as a founding technical member with real ownership.   What You’ll Do

• Own the design, training, and optimisation of foundation models and AI infrastructure end-to-end
• Build and improve large-scale distributed training and high-performance inference systems
• Drive AI safety research and alignment work, developing evaluation frameworks and safety mechanisms
• Contribute to RL and post-training methodology: RLHF, RLAIF, reward modelling, and self-improving systems
• Act as an external-facing technical profile, including participation in investor and strategic conversations

  What We’re Looking For

• Worked at one of the top three frontier AI labs: OpenAI, Anthropic, or DeepMind
• 3–8 years of experience; strong profile matters more than seniority
• Deep expertise in AI safety, model fine-tuning, or AI platform / infrastructure engineering
• Hands-on experience with PyTorch, CUDA, DeepSpeed, Megatron-LM, vLLM, or similar
• Comfortable operating with high autonomy in a small, fast-moving global team
• Open to working across time zones with a globally distributed engineering team

  Offer

• Competitive base salary + significant equity package
• Direct report to CTO with wide scope to shape technical direction
• Fully remote, global search

  If this piques your interest, please apply today!