language models, mts @MicrosoftAI, prev co-lead of Olmo @allen_ai, @uwcse, he/him, https://xitter.cf/t.co/5Hm9cx3Urz🧋

Seattle, WA
Joined January 2019
olmo 3 paper finally on arxiv 🫡 thx to our teammates esp folks who chased additional baselines thx to arxiv-latex-cleaner and overleaf feature for chasing latex bugs thx for all the helpful discussions after our Nov release, best part of open science is progressing together!
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I'm also at #colm2026, Mon-Thurs Supporting two papers from @allen_ai days 🐟Olmo Hybrid, 7B hybrid model 🐠Cracks in the Foundation, long context recipes Hoping to have fun chats w folks about scaling LM data & evals, ☺️ unbiased on pretrain, posttrain, all the 🚂s
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for more info on the works, check out original threads by the project leads! Olmo hybrid: xitter.cf/lambdaviking/status/20… Cracks in foundation: xitter.cf/abertsch72/status/2049…
New paper! allenai.org/papers/olmpool This tackles a puzzle we found during the training of Olmo 3: how could two models with nearly identical short-context performance (and trained on the same data!) behave completely differently after long context extension?
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Today we're unveiling Trillium Labs @trillium_labs, a new non-profit to foster the open science of frontier AI. We're building open post-training recipes and will expand into open infra to study RSI, reward-hacking, multi-agent systems, and whatever comes next. We're built around the theory of change that you need more eyes to solve hard technical problems. We have faith in the scientific methods and communities that humanity has built, and worry that AI is becoming too closed to utilize them. Trilliums are wildflowers that bloom briefly in the spring, before the forest canopies fill out. Though they are small, they lay the foundation for the cycles of growth and nourishment through the rest of the year. At Trillium Labs, the recipes will be the slow nutrients for the seasons and the model releases will be the blooms. Building an institution dedicated to this is needed because, much as nature’s trilliums are slow to expand and grow, the open-ecosystem needs time and dedicated resources to catch up. I co-founded with with a long-time friend and collaborator Tom Zick (@thesezickbeats). We're hiring (full time + student collabs/interns), we're fundraising, and we're looking for compute. Please get in touch if you're interested in helping out. Offices based in the Bay Area and Cambridge MA, remote okay. I’m in the Bay Area until for The Curve and COLM to connect with people who are interested. We’re thankful to have initial support from Halcyon Futures and Schmidt Sciences with more funding en route to enable our ambitions of scaling. Our advisors @Thom_Wolf, @HannaHajishirzi, @gneubig and @ctnzr have been instrumental to building the ecosystem that exists today, and I’m stoked to get to keep working with them.
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before leaving, we released our dolma 3.5 data onto HF wout any fanfare, so happy folks r training on it 😍 very cool data mixing problem at this scale & dataset heterogeneity, congratss
There’s an enormous amount of open training data on Hugging Face. What does it take to make it work together 🤗? For Marin’s 535B run, we built on 25T tokens from 152 datasets with licenses permitting training. Here’s the work between downloading those and training a model 🧵
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happening now at Hall A #1809, mining the web for diverse, natural “how to do X” instructions!
How2Everything will appear in ICML 2026! See you in Korea 🫡 We mine the web's procedural knowledge to better evaluate & train LLMs to generate valid step-by-step instructions, read more at: 🔗 arxiv.org/pdf/2602.08808
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happening now 5pm at Hall A #2108! come chat w us about data mixing under token constraints, changing data, etc #ICML2026
excited to see frens at #icml2026 & present 🐟 Olmix: efficient data mixing under token constraints & evolving data domains 🐡 How2Everything: mining the web for diverse procedural tasks for train & eval 🐠 happy to chat data & evals, both pre & post-training
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excited to see frens at #icml2026 & present 🐟 Olmix: efficient data mixing under token constraints & evolving data domains 🐡 How2Everything: mining the web for diverse procedural tasks for train & eval 🐠 happy to chat data & evals, both pre & post-training
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Data mixing - determining ratios across your training datasets - matters a lot for model quality. While building Olmo 3, we learned it’s hard to set up a method that finds a strong mix, and hard to maintain that mix as datasets change throughout development. Introducing Olmix👇
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How2Everything will appear in ICML 2026! See you in Korea 🫡 We mine the web's procedural knowledge to better evaluate & train LLMs to generate valid step-by-step instructions, read more at: 🔗 arxiv.org/pdf/2602.08808
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Kyle Lo retweeted
I've spent my PhD figuring out how a model learns from data, digging through piles of Spanish math problems, fanfiction, and the depths of StackExchange. Engram opens a new dimension: how a model learns from you - your world, how it evolves, and the threads that tie it all together. Figuring out how to do this well is a wide-open research problem. Join us :)
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Trained some terminal agents with friends! Introducing Tmax, open RL terminal agent models. Under default settings and shorter length (65k) token budgets, tmax outperforms prior open work on terminal use. We are releasing all data+weights+rollouts publically!
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Kyle Lo retweeted
microsoft MAI tech report is a gold mine, one of the most transparent for a model at this scale. this model uses zero synthetic data or distillation from previous models. this means reasoning, agentic behavior, tool use are all learned fully during post-training with no cold start. bold choice that makes it harder and requires more iterations to reach sota, but you get FULL control over your model series and it proves they are serious about being a frontier lab. the tech report is insanely detailed and precise about numbers. to give an example, they give the exact MFU across all the iterations of the model, with the exact changes etc. they also share the full scaling ladder recipe, to my knowledge this is the first time i've seen this in a tech report at this scale let's look at all of this in this likely very long thread 🧵
Super excited to announce seven new world-class MAI models today. They represent what we consider a new era in AI designed to keep you in control and on the frontier. First is our text foundation model, MAI-Thinking-1, exceptionally strong on reasoning and SWE tasks. - It’s a 35B active parameter MoE with a 256K context window. Independent human raters on Surge prefer it for overall quality in blind side-by-sides versus Sonnet 4.6, and it’s achieved 97% on AIME 2025, the key measure of its general-purpose reasoning abilities. - It's at 53% on SWE Bench Pro, placing it right alongside Opus 4.6 on one of the toughest coding benchmarks. - And since we co-designed our models with our own silicon, MAI-Thinking-1 is optimized on our MAIA 200 chip. Benchmarking head-to-head against the GB200, we see 30% better performance per dollar as well as a 1.4x performance-per-watt gain when running our MAI models on the MAIA 200 end-to-end. Next is MAI-Image-2.5 and its Flash variant. Two super strong models now at #2 on the leaderboards, surpassing the score of Nano Banana 2 on image editing. Last for now is MAI-Code-1-Flash, our new inference efficient coding model, especially tuned for VS Code and GitHub Copilot CLI. - Code-1-Flash achieves 51% on SWE Bench Pro, despite having just 5B parameters, putting it closer to Haiku in size but cheaper in cost. All of this is the foundation for Microsoft Frontier Tuning. It lets you customize our models to create custom, company-specific agents that only you control. You can make our model, your model. Your data. Your agents. Your moat. Early adopters are already seeing a difference. When we tuned our models for McKinsey’s tasks, MAI delivered the highest win rate, outperforming GPT-5.5 on quality, while being 10x lower on cost. Also really excited to be collaborating with the amazing team at Mayo Clinic to jointly train a new frontier AI model for healthcare. Our announcements today mark another milestone on the road to humanist superintelligence. You can learn more and about our other new models in our latest blog: microsoft.ai/news/building-a…
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happy to share another quality tech report w/ the wider research community 🫶 great read for ppl who want to see all the details for methods + infra for scaling up pretraining & RL, esp detailed discussion about data which is often kept vague by other labs
Super excited to announce seven new world-class MAI models today. They represent what we consider a new era in AI designed to keep you in control and on the frontier. First is our text foundation model, MAI-Thinking-1, exceptionally strong on reasoning and SWE tasks. - It’s a 35B active parameter MoE with a 256K context window. Independent human raters on Surge prefer it for overall quality in blind side-by-sides versus Sonnet 4.6, and it’s achieved 97% on AIME 2025, the key measure of its general-purpose reasoning abilities. - It's at 53% on SWE Bench Pro, placing it right alongside Opus 4.6 on one of the toughest coding benchmarks. - And since we co-designed our models with our own silicon, MAI-Thinking-1 is optimized on our MAIA 200 chip. Benchmarking head-to-head against the GB200, we see 30% better performance per dollar as well as a 1.4x performance-per-watt gain when running our MAI models on the MAIA 200 end-to-end. Next is MAI-Image-2.5 and its Flash variant. Two super strong models now at #2 on the leaderboards, surpassing the score of Nano Banana 2 on image editing. Last for now is MAI-Code-1-Flash, our new inference efficient coding model, especially tuned for VS Code and GitHub Copilot CLI. - Code-1-Flash achieves 51% on SWE Bench Pro, despite having just 5B parameters, putting it closer to Haiku in size but cheaper in cost. All of this is the foundation for Microsoft Frontier Tuning. It lets you customize our models to create custom, company-specific agents that only you control. You can make our model, your model. Your data. Your agents. Your moat. Early adopters are already seeing a difference. When we tuned our models for McKinsey’s tasks, MAI delivered the highest win rate, outperforming GPT-5.5 on quality, while being 10x lower on cost. Also really excited to be collaborating with the amazing team at Mayo Clinic to jointly train a new frontier AI model for healthcare. Our announcements today mark another milestone on the road to humanist superintelligence. You can learn more and about our other new models in our latest blog: microsoft.ai/news/building-a…
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The penalty is a 1-year ban from arXiv followed by the requirement that subsequent arXiv submissions must first be accepted at a reputable peer-reviewed venue. 4/
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community too susceptible to ragebait. if some rando said in person “im gonna vibe a neurips paper in 3 days,” normal reaction wouldn’t be to seriously debate this person on research ethics/quality, it’d be to ignore 🤷🏻‍♂️
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How2Everything will appear in ICML 2026! See you in Korea 🫡 We mine the web's procedural knowledge to better evaluate & train LLMs to generate valid step-by-step instructions, read more at: 🔗 arxiv.org/pdf/2602.08808
LLMs often generate step-by-step instructions, from real-world tasks (how do I file taxes?) to plans for AI agents. Improving this is hard: outputs can sound fluent for steps that don't work, and current datasets cover few domains. How2Everything evals/trains for this at scale. 🧵
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during in Olmo 3 we thought long context is just finding good data nope! model architecture matters & it's hard to recover if mess it up led by @abertsch72, we release many pretrain runs w/ small arch changes and show huge long context performance diffs
Recipes for teaching language models to handle long inputs don't work equally well across model families. We wanted to know why—is it the architecture, the training data, or both? 🧵
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more deets in @abertsch72 's thread: xitter.cf/abertsch72/status/2049… download all the models from HF: huggingface.co/collections/a…
New paper! allenai.org/papers/olmpool This tackles a puzzle we found during the training of Olmo 3: how could two models with nearly identical short-context performance (and trained on the same data!) behave completely differently after long context extension?
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Kyle Lo retweeted
I'm at ICLR presenting Olmix (oral) at the Data-FM workshop this Sunday, April 26 @ 10:30AM! DM me to chat about anything related to data and the model development process / try to find the best açaí + pão de queijo with me 😋
Data mixing - determining ratios across your training datasets - matters a lot for model quality. While building Olmo 3, we learned it’s hard to set up a method that finds a strong mix, and hard to maintain that mix as datasets change throughout development. Introducing Olmix👇
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