Linera is a blockchain protocol designed with low-latency applications in mind. The project draws from academic research initiated at Facebook/Novi, such as the FastPay protocol and the Zef protocol (slides).
River Financial is a financial institution specializing in Bitcoin financial services. It enables clients to manage their Bitcoin brokerage and Bitcoin mining accounts in one place. The company's flagship product, a Bitcoin brokerage, provides sophisticated retail investors with a platform to buy and sell Bitcoin. Additionally, River Mining allows clients to use their capital to mine their own Bitcoin.