Senior/Staff Machine Learning Engineer

At River we are building the world’s most trusted financial institution to empower people to take ownership of their financial lives through Bitcoin, the world’s only incorruptible digital money. We believe in a future where every person will have bitcoin savings, and every business will have bitcoin on the balance sheet. We obsessively design and build delightful products that help our clients buy, sell, secure, and use Bitcoin.

We are looking for a Senior/Staff Machine Learning Engineer to build and own machine learning-driven systems that power automation and decision-making across onboarding, risk, compliance, and operations. You will apply ML and LLMs in production to solve real-world problems. Our core stack includes XGBoost, PyTorch, Python, MLflow, Postgres, and BigQuery.

River is growing quickly and has raised more than $50 million from leading investors, including Goldcrest, Kingsway, Polychain, M13, DG, and Valor. We have also released our company's financials and proof of reserves publicly, so all of our clients and employees can verify the robustness and growth of the business themselves.

What you will be doing

• Design, build, and iterate on machine learning models and LLM-based systems that power critical decisions across fraud, compliance, growth, and operations

  Work with messy, real-world data to identify signals, build features, and continuously improve model performance

  Make practical tradeoffs between model performance, interpretability, and operational cost

  Partner closely with product and operations to identify and solve problems that directly impact experience of hundreds of thousands of clients

  Contribute to backend systems and data pipelines that support model training and inference (without being primarily an infrastructure role)

  Write high-quality, tested code and participate in code reviews

  Take long-term ownership of critical systems as River scales

What we look for in you

• 4+ years of experience building and applying machine learning models in real-world settings, or comparable research experience

  Strong intuition for ML concepts and how they apply in practice (i.e., tradeoffs)

  Experience working on problems involving noisy, imbalanced, or real-world data

  You take ownership of systems and are comfortable solving ambiguous problems

  You have strong judgment around correctness, reliability, and operational risk

  You can translate between technical systems and business/product needs

  You're excited about what we are building at River

Nice to haves

• Experience in fraud/risk, fintech, or other high-signal/noise domains

  Experience with tabular ML and feature engineering-heavy workflows

  Familiarity with LLM-based systems or applied AI use cases

  You have worked at a rapidly scaling company

  Interest in Bitcoin

Location & Salary

• 100% remote option available within the Americas and Europe, with offices in SF, NYC, and Columbus

  Salary range between $150,000 - $250,000 based on skills and experience

  Significant equity stock options

  Medical, Dental and Vision Benefits

  Unlimited PTO

  Parental Leave separate from regular PTO policy

  401k