River

River is a Bitcoin-first financial institution building consumer and business products to save in bitcoin and spend in dollars. The company custodies BTC, publishes proof of reserves, and is profitable. Engineering work includes real-time Bitcoin and USD payments, trading and settlement on an Elixir monolith with a unified GraphQL API; next-generation Bitcoin custody with quorum signing, key ceremonies and geo-redundant infrastructure; scaling ML/AI systems (Python, PyTorch, XGBoost, LLMs) for automation and fraud/risk; a React and React Native rewrite of the consumer app; and porting Lightning Network infrastructure from Go into Elixir. Hiring for Senior and Staff engineering roles in Elixir, React, and ML/AI. Apply at https://jobs.ashbyhq.com/river?utm_source=Zp9nJyqvd4