Today, we're sharing that River AI has raised $1.1 billion, led by @generalcatalyst and @amppublic with strategic investment from @nvidia and @AMD. Additional investors include @ycombinator and @Temasek. We imagine a future where your AI works entirely for you and deeply aligns with your values. Compared to the corporate chatbots of today, it will feel completely different: responsible, curious, and truly yours. Most importantly, you'll own everything: the hardware it runs on, the data it learns from, and the intelligence itself. Our training API is already live and powering incredible work today. This new funding accelerates our push to bring the full personal AI stack to life. Read River AI CEO Igor Babuschkin’s (@ibab) conversation with the New York Times to learn more: nytimes.com/2026/08/11/techn…

River AI is growing and we've published new roles in research, engineering, and operations. Check out our careers site or reach out to our team today. If you want to build the future of personal AI, join us! river.ai/careers

For AI to work with us, it needs to understand us Today, we're introducing Persimmon, the first large-scale model designed to realistically simulate how people talk and interact

We’re sharing a solution to the Navier-Stokes Millennium Prize Problem, one of the deepest problems at the frontier of mathematics. The proof was produced by a group of agents, using an OpenAI next-generation model significantly more capable than GPT-6 Astra. The problem concerns whether the description of smooth three-dimensional fluid motion modeled by the Navier-Stokes equations can break down. It has remained unresolved for roughly 90 years.

You need to build and own your own intelligence: your own agent, your own models, your own memory Join us for the YC Own Your Intelligence Hackathon September 27 in San Francisco events.ycombinator.com/gstac…

We're thrilled to announce that @Cisco_Invests is joining River AI's $1.1B round as a strategic investor. Personal, user-owned AI needs the best of product and infrastructure behind it. @jpatel41 understands both deeply and we're excited to work with him and the @Cisco team.

We can now RL large MoEs with 0 train-infer mismatch! And doing so can improve performance (pictured task: teach Qwen3.6-35B-A3B to play Wordle). Everything is open-source and we did a bunch of ablations. 🧵

.@river_ai_inc has a new vision for personal AI. We co-led River’s $1.1B funding round because we believe in @ibab's ambition to build open-weight models that individuals can train and improve continuously. Watch @htaneja in conversation with Igor. Chapters 02:22 — Co-Founding xAI 04:36 — An AI Experience You Own 05:59 — Betting Early on Open Weights 07:47 — How Do You Make Money on Free Models? 09:25 — Why the US Needs Its Own Open Models 11:27 — Enterprises Want to Control Their AI 13:36 — What Is Continual Learning? 16:56 — An API That Updates the Weights 19:17 — A Personal AI for Everyone 20:46 — The 20-Minute Training Run

How do we create amazing personal AI? Here's a recent talk from River CEO Igor Babuschkin (@ibab) sharing our vision for personal AI and continual learning.

"As a proprietary model builder, you're kind of starting to get squeezed in.” That's @ibab’s take on where the biggest AI labs stand today. He explains how you need the models to get way better to keep margin, but at some level they may be too sensitive to release. This week, I sat down with Igor on Unsupervised Learning. It was a fascinating conversation with someone who has real perspective on the questions everyone in AI is asking right now. From DeepMind's StarCraft project to early reasoning work at OpenAI to co-founding xAI, Igor has had a front-row seat to nearly every major AI breakthrough. He's now the co-founder of River AI, building individualized, locally-run AI models. We discuss: ▪️Why proprietary model labs might be in trouble ▪️What it's like working with Elon ▪️Building Colossus in 120 days ▪️Should enterprises train their own models ▪️What’s left for humans as models get better ▪️Why he left xAI to bet on personal local AI instead ▪️The three bets River is taking ▪️What's stopping AI from moving beyond coding ▪️Reflections on the rapid pace of the past years 0:00 Intro 1:17 Writing Fiction on Where AI Is Headed 4:46 Cracking Agents Beyond Coding 10:29 Why Igor Left to Start River 12:22 River's Three Big Bets 18:06 Weights vs. Memory: The Personalization Debate 22:04 Should Enterprises Train Their Own Models? 25:10 Are Proprietary Labs Losing Their Edge? 32:16 The China Open-Source Problem 44:19 The Elon Call That Started xAI 50:18 Thoughts on Cursor Acquisition 52:16 What's Actually Bottlenecking AI 56:55 Humans, Machines, and Staying Relevant 1:01:29 Igor's Odds This All Goes Well YouTube: piped.video/0aBTpoCX_A8 Spotify: bit.ly/4h3UJWt Apple: bit.ly/4w0BCAs

River API is now available to everyone. Fine-tune and run RL on frontier open models. Fast, cheap, and scalable. Go to console.river.ai/ to try it out!

For my first post, I’m sharing a letter @NVIDIA signed on why open models matter. AI will transform every industry, power every company, and be built by every country. Open models strengthen safety and cybersecurity, accelerate innovation and diffusion, and enable sovereignty. The world needs both frontier closed models and frontier open models. images.nvidia.com/pdf/Open-W…

We've received plenty of applications for the API waitlist and have opened up access to a number of enterprises and researchers already. We're improving the API based on your feedback, and we expect to open up to the public in the next few weeks.

River AI is building personal AI owned & shaped by you. We are hiring exceptional talent across the stack: * Research * Software Engineering * Product Development * Data * Hardware, RTL Design Engineer * Hardware, Design Verification Engineer * Hardware, Physical Design Engineer * Hardware, Performance Engineer * Hardware, Compiler Engineer * Open Application, Exceptional Talent river.ai/careers We are a small, elite team of researchers, builders, and pioneers from the world's leading AI labs. If you want to do the most ambitious work of your career alongside, apply today!

Introducing River API. Fine-tune and RL train leading open-source models at scale, ranging from 35B to 1T params. We’ve been using it internally to power our research and we love it. Today, we are opening up our public waitlist. Own your intelligence!

We are incredibly excited to announce River AI. Our mission is to create personal AI that is owned and shaped by you. Today’s best AIs are controlled by a few large corporations. We are building the alternative: a new, personal stack for AI that works entirely for you, shares your values, and operates on your terms.