Sam Fraser retweeted
Trinity-Large-Thinking will be deprecated October 26.
Trinity was a milestone for us. Thank you to everyone who used it. We're preparing something new and will have more to share soon.
DeepSeek, Kimi, and GLM models remain available on the Arcee endpoint.
Trinity was a milestone for us. Thank you to everyone who used it. We're preparing something new and will have more to share soon.
DeepSeek, Kimi, and GLM models remain available on the Arcee endpoint.
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Sam Fraser retweeted
Thrilled to announce I've joined @arcee_ai as Head of Compute / Infrastructure to build the model stack for the next generation of American open source frontier intelligence.
I'm hiring. If you're interested in working on a rigorous team at the frontier of infra, DMs are open!
I'm hiring. If you're interested in working on a rigorous team at the frontier of infra, DMs are open!
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onward
Today, we are announcing our Series B funding round, valuing the company at more than $1B.
This round accelerates our next-gen Trinity models across diverse infrastructure, expands our work with the DOE and national labs on Genesis-Science-1, and enables us to build the platform aluate, deploy, and operate open models in production.
We are grateful to our team, partners, open-source community, and investors.
Led by @Vista_Equity, Cambium Capital, and @emergencecap, with participation from AI10 Ventures, @Hitachi, IAG, @M12vc, @p7ventures, and @Wipro.
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Sam Fraser retweeted
nac v0.1.4 is out.
What’s new:
• Conversation forks
• Stop waits for cleanup
• Project sessions stay put
• Bug fixes
➡️ Upgrade now with: nac-web upgrade
github.com/arcee-ai/nac/r…
What’s new:
• Conversation forks
• Stop waits for cleanup
• Project sessions stay put
• Bug fixes
➡️ Upgrade now with: nac-web upgrade
github.com/arcee-ai/nac/r…
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Sam Fraser retweeted
nac v0.1.3-rc.575 is out.
What’s new:
• Release skill
• Stdio MCP fix
• Pricing tiers
• Bug fixes & general cleanup
➡️ Upgrade now with: nac-web upgrade
github.com/arcee-ai/nac/r…
What’s new:
• Release skill
• Stdio MCP fix
• Pricing tiers
• Bug fixes & general cleanup
➡️ Upgrade now with: nac-web upgrade
github.com/arcee-ai/nac/r…
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Sam Fraser retweeted
We've added deepseek-v4-pro-0813 to the Arcee Open Models API.
You can access the model directly in the platform now: platform.arcee.ai
You can access the model directly in the platform now: platform.arcee.ai
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Sam Fraser retweeted
really cool to see people pick nac up internally, and to see it go from a small project to this. i use this for everything right now, from running and babysitting experiments to patching bugs to more auto-research-shaped tasks. the team really polished it up, take a look!
We’re thrilled to introduce NAC, and a beta of our expanded Open Models API.
NAC is an internal harness our research team has used daily since April. It’s built exclusively for long running, asynchronous and hands off work.
A significant portion of all code committed to our ning and data pipelines in the last 3 months has been powered by NAC, often driven remotely from our phones.
Started as an internal side project from @stochasticchasm, it was quickly adopted internally, and we’re happy to open it up to everyone.
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there are a lot of harnesses out there. we hope you have room to try one more.
most of our team uses nac. hope you like it.
most of our team uses nac. hope you like it.
We’re thrilled to introduce NAC, and a beta of our expanded Open Models API.
NAC is an internal harness our research team has used daily since April. It’s built exclusively for long running, asynchronous and hands off work.
A significant portion of all code committed to our ning and data pipelines in the last 3 months has been powered by NAC, often driven remotely from our phones.
Started as an internal side project from @stochasticchasm, it was quickly adopted internally, and we’re happy to open it up to everyone.
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Today we’re open-sourcing nac, a long-horizon agent harness, and launching the Arcee open models API.
nac is built for complex, multi-step workloads. It connects directly to the open-weight models now available on our platform, and works with Codex auth as well.
Alongside Trinity-Large-Thinking, the API now includes deepseek-v4-flash, inkling-small, deepseek-v4-pro, GLM-5.2, and Kimi-K3.
This is an important step toward building a strong ecosystem around open-weight models. More announcements to come.
nac is built for complex, multi-step workloads. It connects directly to the open-weight models now available on our platform, and works with Codex auth as well.
Alongside Trinity-Large-Thinking, the API now includes deepseek-v4-flash, inkling-small, deepseek-v4-pro, GLM-5.2, and Kimi-K3.
This is an important step toward building a strong ecosystem around open-weight models. More announcements to come.
Today we're open-sourcing nac, an agent harness for long-running tasks, and launching the Arcee open models API beta.
Nac is available now under Apache 2.0 on GitHub, built for developers running complex, multi-step engineering workloads.
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Sam Fraser retweeted
Easiest co-signature of my life.
The case for open-weight models extends far beyond a small group of highly regulated institutions. It matters to any company building AI deeply into its product.
A software company may need to preserve model behavior across releases. A product une to their exact tasks, reduce inference costs, run closer to the customer, or support deployments where a remote API is a poor fit. A startup may simply decide that its core product should not depend forever on another company’s pricing, rate limits, release schedule, or product decisions.
Open weights expand the set of decisions those teams can make for themselves. It allows companies to create differentiated products instead of assembling the same remote services as everyone else.
We started Arcee because we believed businesses would eventually need more than access to intelligence. They would need the ability to shape and operate it.
I’m glad that view is gaining support. Now we have to keep building models worthy of that responsibility.
The case for open-weight models extends far beyond a small group of highly regulated institutions. It matters to any company building AI deeply into its product.
A software company may need to preserve model behavior across releases. A product une to their exact tasks, reduce inference costs, run closer to the customer, or support deployments where a remote API is a poor fit. A startup may simply decide that its core product should not depend forever on another company’s pricing, rate limits, release schedule, or product decisions.
Open weights expand the set of decisions those teams can make for themselves. It allows companies to create differentiated products instead of assembling the same remote services as everyone else.
We started Arcee because we believed businesses would eventually need more than access to intelligence. They would need the ability to shape and operate it.
I’m glad that view is gaining support. Now we have to keep building models worthy of that responsibility.
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.
rontier closed models and frontier open models.
images.nvidia.com/pdf/Open-Weigh…
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Sam Fraser retweeted
Today we are announcing a partnership with the Department of Energy to build Genesis-Science-1, an open model for scientific research. GS1 is an American open-weight AI model and governed research harness designed to complete scientific computing workflows while preserving a its work.
This model will be shaped by the people who know scientific work inside and out. @ENERGY is opening a contributor program for researchers, laboratories, universities, companies, and nonprofits, and we're speaking with infrastructure partners who can add training or evaluation capacity.
There’s still lots of work ahead, and we hope you’ll help us build in the open, starting with GS1.
This model will be shaped by the people who know scientific work inside and out. @ENERGY is opening a contributor program for researchers, laboratories, universities, companies, and nonprofits, and we're speaking with infrastructure partners who can add training or evaluation capacity.
There’s still lots of work ahead, and we hope you’ll help us build in the open, starting with GS1.
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Sam Fraser retweeted
🤝 @arcee_ai, an American AI lab, built its frontier open model family on NVIDIA Blackwell Ultra.
Its flagship MoE model, Trinity-Large-Thinking, was RL post-trained using NVIDIA NeMo open libraries.
Arcee optimized agentic model inference with NVIDIA Dynamo and vLLM, along networking, to deliver low token cost, achieving:
✅ 3T+ tokens served on OpenRouter in its first two months
✅ $0.90 per 1M output tokens
✅ 2nd on PinchBench for open agentic models
Explore Arcee's open models, powered by NVIDIA ➡️ nvda.ws/457XCOw
Its flagship MoE model, Trinity-Large-Thinking, was RL post-trained using NVIDIA NeMo open libraries.
Arcee optimized agentic model inference with NVIDIA Dynamo and vLLM, along networking, to deliver low token cost, achieving:
✅ 3T+ tokens served on OpenRouter in its first two months
✅ $0.90 per 1M output tokens
✅ 2nd on PinchBench for open agentic models
Explore Arcee's open models, powered by NVIDIA ➡️ nvda.ws/457XCOw
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Honored to be named in the 2026 #100WomenInAI. Thanks for all the love!
Our head of product, @samfrannn, just made the 2026 100 Women in AI list.
Sam works at the seam between our models and our products. She figures out which capabilities are worth building on, and how they should feel in someone’s hands.
Hard to think of a better pick.
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Sam Fraser retweeted
@Jason the two US companies that are most seriously pushing open models above 100B params are NVIDIA and Arcee
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Sam Fraser retweeted
Trinity-Large-Thinking is now free to use in @OpenRouter through May 23.
This model is a great choice for those working with complex agentic workflows, heavy multi-turn tool use, and long-horizon routing.
The free endpoint is live: openrouter.ai/arcee-ai/trini…
This model is a great choice for those working with complex agentic workflows, heavy multi-turn tool use, and long-horizon routing.
The free endpoint is live: openrouter.ai/arcee-ai/trini…
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Sam Fraser retweeted
Trinity-Large-Thinking, @arcee_ai's latest model, is now free on Nous Portal for the next week
Sign up for Nous Portal to use it in your Hermes Agent today
Sign up for Nous Portal to use it in your Hermes Agent today
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First wave of approvals for the @arcee_ai TRINITY Builders Program are out.
If you weren’t selected this round, don’t worry, we’ll be reviewing all remaining applications in the next wave.
Thank you for the incredible interest and ideas so far!
If you weren’t selected this round, don’t worry, we’ll be reviewing all remaining applications in the next wave.
Thank you for the incredible interest and ideas so far!
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