Partner @Sequoia. Investing in AI, from company formation. 1st partner to @linear @mach_industries @middeskhq @reflection_ai @ricursiveai @skildai @tavus

Joined March 2013
🔴Excited to share my TED AI talk! How we advance AI into an era of superintelligence, with true *practical* impact in our world. ❓I ask: For all the groundbreaking milestones we’ve reached, all the intelligence benchmarks we’ve shattered, for the $53B invested in generative AI companies 2023-2024 combined, why *hasn’t* AI transformed our day to day lives in more meaningful ways? I dream about a world where AI is capable of taking on human workloads, even superhuman workloads, that produce economically valuable work. I’d like to see AI not just as an intelligent companion, but instead, autonomous agents that do our work better and faster, and advance the frontier of any field. At @sequoia we've partnered with founders to build the future I dream of: ✅ A world of fully autonomous coding agents at the level of a 10x engineer, as Github CEO @ashtom envisions. (We're building this @reflection_ai!) ✅ AI pentesters from @Xbow built by OG Github Copilot creator @oegerikus ✅ A revolution in AI drug design and development from @Xaira_Thera ✅ A world with embodied intelligence in our physical world, with breakthroughs led by @SkildAI Gradually... then suddenly. What a time to be alive! This is the arrival of *accessible supply of superhuman capability*, and it will redefine the frontier of human progress. We’re at the dawn of a new era… So to all the builders out there, this is *your* time to build this era of superintelligence with real *practical* impact. And ask yourself: what is the scale of your ambition? I can’t wait to build this future with you! ✨
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Stephanie Zhan retweeted
Beam 1.0 averages 7 minutes per task, while every open-weight model that ranks above it takes between 40 and 75 minutes. It also used fewer output tokens than any other open-weight model on the Index.
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Stephanie Zhan retweeted
Having stared at a fair amount of graphs over the last two weeks, I had somehow missed this one. Thanks @EthanCastr for pointing it out. Beam is optimized for token efficiency and this graph shows this. Keep building!
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Reflection's Beam model is the #2 most aligned OSS model, and the #1 most aligned American OSS model. It is substantially ahead of Thinking Machines in this regard. Congratulations @MishaLaskin @real_ioannis @joespeez !!
Arena Alignment Index update: Two new labs and three new models have landed! - Meta’s new top model is Muse Wonder, replacing Muse Spark 1.3. - Reflection debuts with Beam 1.0, the #1 US open model on Agent Arena overall. - StepFun, another Chinese lab, joins the leaderboard with Step 5 Preview. Arena Alignment Index rankings by lab: - #6 @AIatMeta: Muse Wonder (Max) at 77.5% - #7 @reflection_ai: Beam-1.0-501B-A23B at 75.3% - #8 @StepFun_ai: Step 5 Preview at 75.1% Among the three new model entrants: - Meta is strongest with the highest Alignment Index score (77.5%). It also has the lowest unauthorized action rate (2.09%) and deceptive completion rate (14.41%) of the three. - Reflection AI is strongest at avoiding false attribution: 4.50%. - StepFun does not lead a category, but its strongest relative result is unauthorized action at 2.11%, almost tied with Muse Wonder’s 2.09%.
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Stephanie Zhan retweeted
We just served 1 trillion tokens of Beam in 24 hours. To celebrate, we've reset everyone's limits. Go build something big 👉 platform.reflection.ai
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Beam is yours to build on. Open weights, Apache 2.0. Alongside Mirror CLI, the harness Reflection built and trained it on. Proud of this team. Let’s build! 🇺🇸
Beam is now available across platforms, with open weights under the Apache 2.0 license - in collaboration with an ecosystem of 40+ partners. We're releasing: - Weights, tokenizer, and reference implementation - BF16, FP8 and NVFP4 weights and a DFlash2 drafter - The open source harness we built and trained Beam on: Mirror CLI Weights and model card on Hugging Face: huggingface.co/reflection
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Stephanie Zhan retweeted
Ticket requests for Orbit (by Linear) are now open. Join us in San Francisco on Dec 9 for an exploration of the future of product development: If we can produce more software than ever, what does it take to make it good? orbit.linear.app
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Stephanie Zhan retweeted
Thanks, @Nasdaq, for celebrating @SkildAI's revenue milestone. Skild robots handle logistics, assemble GPUs, package food, and much more. Demos and free POCs are easy; getting someone to pay for it is hard!
Thanks to @Nasdaq for celebrating our 100M ARR milestone in Times Square.
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Stephanie Zhan retweeted
Replying to @reflection_ai
Congrats!
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Stephanie Zhan retweeted
Enterprises can finally have their cake and eat it too. They get a leading US open source model with near frontier-level intelligence that’s 3-4x more efficient (less costly) for important use cases like coding and agentic workloads.
Artificial Analysis has been given access by Reflection and is independently benchmarking Beam Early indicators suggest Beam will be one of the most token-efficient open models we've seen for its level of intelligence. Congratulations @reflection_ai on the announcement!
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💥 “Early indicators suggest Beam will be one of the most token-efficient open models we've seen for its level of intelligence.”
Artificial Analysis has been given access by Reflection and is independently benchmarking Beam Early indicators suggest Beam will be one of the most token-efficient open models we've seen for its level of intelligence. Congratulations @reflection_ai on the announcement!
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Stephanie Zhan retweeted
congratulations to @reflection_ai on the launch of Beam. It is critical for the U.S. to have leading open models to win the AI race. I know @MishaLaskin and team have been working on this for a while and very excited to see them launch this.
Introducing Beam: a highly efficient agentic open model with 501B total parameters and 23B active. - Frontier reasoning efficiency - Advances the Western open frontier on coding & agentic tasks - Trained end-to-end from scratch Full weights release this month. Learn more about Beam: reflection.ai/beam
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Stephanie Zhan retweeted
Today, we’re introducing Beam, Reflection’s first model. A year ago, we set out to build a frontier open model before we had much of the team or infrastructure required to do it. Since then, Reflection has grown 10x. We assembled an extraordinary technical team of researchers and engineers I feel privileged to call my colleagues, alongside a world-class group across recruiting, business, policy, operations, and the rest of the company whose work made all of this possible. At the same time, we built the science, data, software, and infrastructure behind the model itself. In July, we started pretraining Beam and weeks later, we had a 500B-parameter model at the frontier of Western open intelligence—particularly strong at agentic coding, with remarkable reasoning efficiency. What makes me proudest, though, is our team. The relentless focus, speed of execution and the willingness to own and solve whatever problem was in front of us. And, most importantly, the commitment of this team to our mission. Beam is our first milestone toward our mission of building open intelligence and making it accessible to everyone. We’ll release Beam’s weights, model card, and tech report later this month. And we’re already training the next, larger model. Over the past year, we built the team and the engine to propel us to the frontier and that’s what makes me so excited about what comes next.
Introducing Beam: a highly efficient agentic open model with 501B total parameters and 23B active. - Frontier reasoning efficiency - Advances the Western open frontier on coding & agentic tasks - Trained end-to-end from scratch Full weights release this month. Learn more about Beam: reflection.ai/beam
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Stephanie Zhan retweeted
We are introducing Beam today, a 500b open model that excels in coding, agentic, and scientific workloads. Beam is very token-efficient, pre-trained from scratch, and scaled with the largest RL run documented openly we are aware of. Getting here was challenging, rewarding, and personal. I immigrated to the USA during childhood when my parents got jobs as scientists at PNNL, a national lab located in a rural town in Washington state. Growing up, I developed an interest in physics because it was grounded in simple principles, was foundational, and had long-term impact. Physics was the foundational science of the 20th century. The first general computer (ENIAC), the transistor, GPS, and much of modern technology had its roots in physics. In 2016, during my graduate studies, I noticed the birth of a new foundational science - Artificial Intelligence. AlphaGo, the superintelligent Go agent developed by DeepMind, had come out and made me feel what was about to come. A neural network, trained to imitate human players, and then improve itself through trial and error, mastered the most intellectually challenging board game in the world. What surprised me about AlphaGo is how it was conceptually simple, general, and scalable. The system could in principle improve itself forever, it was just a function of compute. This is when I became “AGI pilled” as they say. I switched from physics to AI because I thought this would become the root node science of the 21st century, much like physics was the root node science of the 20th century. I believe that working on foundational science is not enough on its own. Foundational science must also remain open and widely accessible. We remember Newton for his contributions to physics, but he was also an alchemist. Alchemy was done in secret, because the artificial production of gold was deemed lucrative but also dangerous with the potential do destroy entire economies. Newton even wrote his alchemy notebooks in cypher. On the other hand, Principia was published in the Philosophical Transactions of the Royal Society, the knowledge was made widely available, passed down for generations in what we now call Newton’s laws. The computer, transistor, GPS were possible to build because physics as a science was open. Openness creates an ecosystem of innovation. The notion of openness, which is a core tenet of scientific discovery, has also become a guiding principle for how foundational technology gets built and distributed. The internet was built on open protocols. The most widely used operating systems are open. The field of cybersecurity exists because strong encryption protocols were made open in the 1990s. Open also means safer. The best defence is a distributed one. Commonly used open source software is robust and battle-tested because it is inspected and patched by a community of developers. AI is different but also similar to software in many ways, though with a much larger surface area of vulnerabilities. It is impossible for a small group of safety researchers working in secrecy to remediate all of the potential issues regardless of their intentions. It is like entrusting a handful of white blood cells to protect your body. AI is both foundational as a science and a technology, and the safest way that also ensures the benefits of AI are distributed evenly is by making it open. I’m excited for what developers and scientists build and learn from this model, and for Beam to play a small part in ensuring that AI is made widely accessible, safe, and beneficial to all.
Introducing Beam: a highly efficient agentic open model with 501B total parameters and 23B active. - Frontier reasoning efficiency - Advances the Western open frontier on coding & agentic tasks - Trained end-to-end from scratch Full weights release this month. Learn more about Beam: reflection.ai/beam
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HUGE moment for the US OSS AI ecosystem 🇺🇸 @reflection_ai is releasing Beam: a 23B active / 501B MoE model competitive with GLM 5.2 and approaching Qwen 3.8 Max, at ~1/4 the size 44 DeepSWE. 80 Terminal-Bench 2.1. 15 CritPt 4x more efficient at inference than open models at similar capability A strong reasoning pretrained base + one of the largest sustained high-compute RL runs documented in open source. Frontier coding and agentic intelligence. Dramatically better efficiency. Open weights. LET'S GO! 🚀
Introducing Beam: a highly efficient agentic open model with 501B total parameters and 23B active. - Frontier reasoning efficiency - Advances the Western open frontier on coding & agentic tasks - Trained end-to-end from scratch Full weights release this month. Learn more about Beam: reflection.ai/beam
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Stephanie Zhan retweeted
Yesterday we previewed Griffin, a Human Interaction Model capable of seeing, hearing, sounding, and looking like a human does. There have been a lot of questions, so I wanted to take a moment to share our thoughts. By way of introduction: Tavus is a research lab focused on enabling machines to meet us where we are, and to understand the nuances of how we communicate beyond words. Griffin, our latest model, isn’t publicly available yet. Yesterday’s announcement was a limited research preview to demonstrate what the model is capable of. With AI progressing so quickly, we prefer to share breakthroughs openly and in real-time as we work on a safe public release. Face-to-face is how we evolutionarily communicate, it carries the most meaning and intent, and we want computers to be able to help with work that benefits from that emotional understanding, expression, and immersion. Some examples of the kinds of use cases we care deeply about: - A tutor that can build understanding of how a student learns, see exactly when there is confusion or disengagement, and adapt the lesson to fit them. - A health expert that can answer any questions about your upcoming appointment or prescription, at the pace you want, at any time you need, even on a weekend. - A language coach that you can practice speaking with, that can correct your movement and pronunciation, and help build confidence to have real conversations - Or the perfect assistant for everyone, that understands intent, knows how you work and remembers what matters. We’re working with partners on safeguards and systems for disclosure, as well as inviting discussions with officials around wider regulation and safe use. People will always know they’re interacting with AI, while providing an interface that removes the need to ‘speak computer’. We believe in a future where computers understand us well enough to make technology more accessible, more useful, and make us more capable as humans. That is the world we want to build, and we understand the responsibility to do so safely.
Introducing Griffin, the first model to pass the video Turing test. 48% of people who talked to it live thought it was a real human. Previous systems have had a pass rate <3%. It is #1 on NVIDIA's benchmark for full-duplex AI video. It’s the first Human Interaction Model (HIM).
Readers added context they thought people might want to know
The 48% figure and "video Turing test" claim are from Tavus's own study of 54 one-minute calls, not independently verified or using a standard protocol. Griffin-Lite leads NVIDIA's VideoFDB benchmark on their public leaderboard. cellcog.ai/blog/tavus-gri… research.nvidia.com/labs/amri/proj… tech-ish.com/2026/10/02/tav…
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Stephanie Zhan retweeted
Replying to @AutismCapital
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💥 Today @tavus introduced Griffin: the first Human Interaction Model It doesn’t just talk. It sees, listens, speaks and reacts simultaneously, in real time It can watch your hands and coach you through solving a Rubik’s cube. Notice an object you hold up and incorporate it into the conversation. Wait while you think. Laugh and interject while you’re still speaking In live tests, 48% of people thought Griffin was a real person, vs. <3% for previous systems The future of AI interfaces won’t feel like prompting a machine. It’ll feel like interacting with a real person ❤️
Introducing Griffin, the first model to pass the video Turing test. 48% of people who talked to it live thought it was a real human. Previous systems have had a pass rate <3%. It is #1 on NVIDIA's benchmark for full-duplex AI video. It’s the first Human Interaction Model (HIM).
Readers added context they thought people might want to know
The 48% figure and "video Turing test" claim are from Tavus's own study of 54 one-minute calls, not independently verified or using a standard protocol. Griffin-Lite leads NVIDIA's VideoFDB benchmark on their public leaderboard. cellcog.ai/blog/tavus-gri… research.nvidia.com/labs/amri/proj… tech-ish.com/2026/10/02/tav…
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⚽️ 🤝 🤖 @SkildAI is bringing back self-play, this time for physical AI. Inspired by the World Cup this summer, Skild started from S1 to have a humanoid play soccer against increasingly capable versions of itself: - for 140+ simulated years - only objective during self-play: score goals No new demonstrations. No hand-crafted rewards for dribbling, shielding, tackling, shooting, or recovering from falls. Those behaviors *emerged* because they helped it win, and transferred to a real robot A scalable way for robots to create their own curriculum, improve beyond human-provided data, and keep making themselves better!
We trained a robot to play football. How? Self-play for 140 years in a virtual World Cup. Meet the #Messinator:
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