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PostHogPostHogUnited Kingdom

AI Research Engineer

Researches and productionizes machine-learning models for session replay analysis, user behavior prediction, and synthetic testing. The role requires strong mathematics, PyTorch, systems programming in Rust/CUDA/C, and a product-oriented approach to shipping.

Salary not listed
HybridAI Research

About the job

Responsibilities

  • Research and develop models for PostHog’s self-driving product and Deep ML systems.
  • Bring research innovations into production with a strong focus on shipping usable products.
  • Explore session replay analysis using DOM mutation data to improve speed, cost, and scalability.
  • Develop user behavior prediction systems to identify drop-offs, suggest improvements, and potentially improve conversion rates.
  • Investigate synthetic user testing to detect confusing flows or breakages before release.
  • Work closely with customers and influence the products shipped by a new AI Research team.

Requirements

  • Strong background in mathematics, or previous experience training models; strong math skills are required in either case.
  • Strong experience with PyTorch.
  • Strong ability to code in Rust, CUDA, or C; Rust is preferred.
  • Solid understanding of Transformers.
  • Product mindset and willingness to build and ship products.

Nice to Have

  • PhD.

Compensation and Benefits

  • Hybrid-remote position based out of the London office.

Exclusions

  • This is not a purely theoretical or Jupyter-notebook-focused role.
  • Research and publishing are supported, but shipping takes priority.

Skills

PyTorchRustCUDACTransformersMachine LearningDeep LearningMathematics

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