River AI Raises $1.1B in Seed/Series A Round Led by General Catalyst

River AI Raises $1.1 Billion in Seed/Series A Funding

AI startup River AI has secured $1.1 billion in a seed/Series A funding round led by General Catalyst and AMP PBC.

The round includes participation from Nvidia, AMD Ventures, Y Combinator, and Temasek.

Founded by Igor Babuschkin, a former xAI co-founder with previous AI experience at DeepMind and OpenAI, River AI emerged from stealth in June 2026 with a focus on building a new approach to personal AI assistants.

Rebuilding the AI Stack

River AI aims to develop AI systems that can become personally trainable assistants rather than focusing primarily on replacing human workers.

The company's broader vision involves rebuilding the AI stack across training, models, the product layer, and hardware designed to bring personal AI closer to users.

Babuschkin envisions AI agents becoming a normal part of everyday life, functioning as personalized assistants that understand their users and work on their behalf.

Training AI Models Instead of Prompting

River already offers an API that allows developers to work with open models and customize them using reinforcement learning (RL) and low-rank adaptation (LoRA) fine-tuning.

The company positions this approach as an alternative to traditional prompt engineering.

Rather than simply prompting models that users do not control, River aims to allow developers to train open models into customized models that can then be deployed through an API.

Enterprise AI Infrastructure

River's technology is also aimed at enterprises looking for greater control over their AI model strategy.

The company is building what it describes as a neocloud offering designed to simplify post-training workflows, particularly reinforcement learning.

River says enterprises can complete complex reinforcement learning runs in 15 to 20 minutes without requiring a dedicated infrastructure team.

The company also claims its approach can provide two to four times the cost savings compared with closed-source alternatives.

Building Toward Personal AI Agents

River's longer-term vision is centered around AI agents that individuals can train themselves and use on their own behalf.

The company sees a future where users can have personalized agents that understand their preferences, context, and needs.

This vision comes as locally running personal AI agents and AI-capable hardware continue to develop.

Founding and Leadership

River AI was founded by Igor Babuschkin, whose previous experience includes AI roles at DeepMind and OpenAI as well as co-founding xAI.

The company emerged from stealth in June 2026 and has already launched its API product.

Funding to Build the AI Stack

The $1.1 billion financing gives River AI significant capital to develop its model-training technology, product infrastructure, and broader personal AI vision.

The company is entering an increasingly competitive AI market where enterprises and developers are seeking greater control over models, customization, and AI infrastructure.