@atalwalkar
Today, we're announcing our Series B: $200M at a $3.1B valuation, and the release of Arena's Alignment Index.
AI is advancing faster than our ability to evaluate it. The world needs a neutral third party to measure how safe and aligned AI actually is once it's in the hands of real people. That's the role Arena is stepping into today.
The Alignment Index is built from real-world agent traces, starting with three signals: Unauthorized Action, False Attribution, and Deceptive Completion, with results for over 20 frontier models launching today.
Hear more from our CEO @ml_angelopoulos below, and read the full breakdown, and more details about our company growth in thread.
This funding will allow us to go further on safety signals, agentic capabilities, and modalities. It will also allow us to grow the company to match the scale of our mission. Today, we’re still a nimble team of 90, and we're looking for people to join us across research, product, engineering, and more. Come build with us.
As AI gets more capable and autonomous, understanding how well it can safely and effectively work for people only matters more. That's what Arena is built to measure and advance.
Thank you to our community, our investors, and everyone building with us!
Take a look at our open roles if you want to join us (link in bio).View quoted post on X
Starting tomorrow, our lab will hold an open-source week: 2 software frameworks, 4 papers, all building a coherent ecosystem.View quoted post on X
The theme: Frontier AI on Hardware You Own
Blog post: timdettmers.com/2026/09/21/dla…
SoTA results in:
Autocompaction
Autonomous Research
Model compression
Test-time scaling
Deep Research
And a healthcare RL environment giving you a new level of complexity to train healthcare agents.
The ecosystem that we will release is built to be as usable as possible. Agent sessions that run overnight and go on for tens of millions of tokens is made easy. Model compression of a model is automatic: you just get a good model that runs fast locally -- no expertise required. An autonomous research that works out of the box.
Our ecosystem enables a new level of work that can be done locally.
Game development remains one of the most-requested, and most-challenging, categories on Arena.
@iamwaynechi, PhD candidate at Carnegie Mellon University and research intern at Arena, just walked us through GameDevBench: a benchmark built from real tutorials that turns game development into verifiable, deterministic tasks.
How do top frontier models perform on tasks a human beginner could complete in under an hour, and is the biggest bottleneck coding or multimodal understanding?
Check out Wayne’s full talk to hear results and learn more about GameDevBench: youtube.com/watch?v=yoHcvr…View quoted post on X
Best commentary on the HuggingFace Incident I've seen so far. youtube.com/watch?v=l5wvqK…View quoted post on X
