Xiaobin Wu retweeted
We are taking another small step today towards making Grok truly useful.
For him to succeed he must exist in an environment where success is in the set of possible outcomes.
The team is working to provide him access to same tools, context, and signals that we have in our lives.
it is fast
Introducing Grok 4 Fast, a multimodal reasoning model with a 2M context window that sets a new standard for cost-efficient intelligence.
Available for free on grok.com, grok.x.com, iOS and Android apps, and OpenRouter.
x.ai/news/grok-4-fast
Xiaobin Wu retweeted
We’re opening an office in Seattle
Come join us!
x.ai/careers
Xiaobin Wu retweeted
HACKATHON in SF
@xai + @vercel
September 11th, 5pm - 10pm
REGISTER: partiful.com/e/sa3etfyhGd50T…
Build something wild, weird, or downright wonderful!
Two Tracks, pick one:
1. Vibe Builder Prize - a more general category, many can fit here. UI friendly, fun category.
2. Interface Paradigm Prize - this one requires more creativity. for projects with innovative and new approaches to interacting with AI.
Guidelines
• Teams of 4 max. (form a crew on-site or roll solo)
• Judged on innovation, functionality, and best use of xAI and v0
• Must be a confirmed attendee!
Xiaobin Wu retweeted
Introducing Grok Code Fast 1, a speedy and economical reasoning model that excels at agentic coding.
Now available for free on GitHub Copilot, Cursor, Cline, Kilo Code, Roo Code, opencode, and Windsurf.
x.ai/news/grok-code-fast-1
Xiaobin Wu retweeted
Today was my last day at xAI, the company that I helped start with Elon Musk in 2023. I still remember the day I first met Elon, we talked for hours about AI and what the future might hold. We both felt that a new AI company with a different kind of mission was needed.
Building AI that advances humanity has been my lifelong dream. My parents left the Russian Federation after the collapse of the USSR in search of a better life for their kids. Life wasn’t always easy as immigrants. Despite the hardships, my parents believed that human values were priceless: values like courage, compassion, curiosity for understanding the world. As a child, I admired scientists like Richard Feynman and Max Planck, who relentlessly pushed the frontiers of physics in order to understand the universe. As a particle physics PhD student at CERN I was excited to contribute to that mission. But the search for new physics was getting harder and harder, requiring bigger and bigger colliders, while new discoveries kept getting fewer. So I began to wonder if superintelligence, not larger colliders, could be the key to unlocking the mysteries of the universe. Could AI develop a consistent theory of quantum gravity? Could AI prove the Riemann hypothesis? In early 2023 I became convinced that we were getting close to a recipe for superintelligence. I saw the writing on the wall: very soon AI could reason beyond the level of humans. How could we ensure that this technology is used for good? Elon had warned of the dangers of powerful AI for years. Elon and I realized that we had a shared vision of AI used to benefit humanity, thus we recruited more like minded engineers and set off to build xAI.
The early days of xAI were not easy. Naysayers told us that we arrived too late to the game, so starting a top AI company from scratch would be impossible. But we believed we could do the impossible. Starting a company from zero required lots of hands-on work. In the beginning I built many of the foundational tools used at the company to launch and manage training jobs. I later oversaw much of the engineering at the company, including Infrastructure, Product and Applied AI projects. xAI’s people are deeply dedicated. Through blood sweat and tears, our team’s blistering velocity built the Memphis supercluster, and shipped frontier models faster than any company in history. I learned 2 priceless lessons from Elon: #1 be fearless in rolling up your sleeves to personally dig into technical problems, #2 have a maniacal sense of urgency.
xAI executes at ludicrous speed. Industry veterans told us that building the Memphis supercluster in 120 days would be impossible. But we believed we could do the impossible. Our goal was to get our training setup running at scale on the Memphis cluster ASAP. Towards the end of our 120 day deadline, we were riddled with mysterious issues with communicating over RDMA between the machines. Elon decided to fly to the datacenter, and we followed. Our infra team landed in Memphis in the middle of the night and got straight to work. After pouring through tens of thousands of lines of lspci output we finally identified a wrong BIOS setting, the root of the problem. Elon was there with us until late into the night. When the training run finally worked, Elon posted our triumph at “4:20am” causing us to laugh out loud. I will never forget the rush of adrenaline that night, and the emotional bonds that we were all in this together. We went to bed feeling like we were living through the most exhilarating time of our lives.
I have enormous love for the whole family at xAI. Our team is truly special - you’re the most dedicated people I’ve ever worked with. Catching up to the frontier this quickly hasn’t been easy. It was made possible by everyone’s diehard grit and team spirit. Thank you to every single person who joined me on this adventure. I want to honor your contributions, your time, your sacrifices, which are never easy. I will always remember working together far into the nights and burning the midnight oil. I will never forget the sacrifices and contributions you’ve made. As I drive away today, I feel like a proud parent, driving away after sending their kid away to college. My heart is brimming with tears of joy, rooting for the company as it grows and matures.
As I'm heading towards my next chapter, I’m inspired by how my parents immigrated to seek a better world for their children. Recently I had dinner with Max Tegmark, founder of the Future of Life Institute. He showed me a photo of his young sons, and asked me “how can we build AI safely to ensure that our children can flourish?” I was deeply moved by his question. Earlier in my career, I was a technical lead for DeepMind's Alphastar StarCraft agent, and I got to see how powerful reinforcement learning is when scaled up. As frontier models become more agentic over longer horizons and a wider range of tasks, they will take on more and more powerful capabilities, which will make it critical to study and advance AI safety. I want to continue on my mission to bring about AI that’s safe and beneficial to humanity. I’m announcing the launch of Babuschkin Ventures, which supports AI safety research and backs startups in AI and agentic systems that advance humanity and unlock the mysteries of our universe. Please reach out at [email protected] if you want to chat. The singularity is near, but humanity’s future is bright!
Xiaobin Wu retweeted
We've upgraded Grok 4's PDF processing abilities:
1. Grok can now seamlessly handle massive PDFs - hundreds of pages and beyond!
2. Grok has a better understanding of the PDF content through sharper recognition capabilities.
Grok's PDF upgrades are now live for all our users on our web and mobile apps. Put Grok to work on your PDFs!
Xiaobin Wu retweeted
looking for excellent engineers to join the force - DM me if interested
Announcing Grok for Government - a suite of products that make our frontier models available to United States Government customers
We are especially excited about two new partnerships for our US Government partners
1) a new contract from the US Department of Defense
2) our products being available to purchase via the General Services Administration (GSA) schedule. This allows every federal government department, agency, or office, to purchase xAI products
We're hiring mission driven engineers who want to join the cause
Xiaobin Wu retweeted
You should be seeing subtle improvements to your post recommendations, especially more banger posts from small accounts.
My feed has noticeably improved. Not yet great, but pretty good.
Xiaobin Wu retweeted
If you’re interested in applying advanced AI to the 𝕏 content recommendation system, join us!
Getting this right is fundamental to improving the collective intelligence of humanity.
The biggest change that people should notice as we shift the recommendation algorithm to use more of @Grok AI is that banger posts from small accounts should start showing up in your feed
Xiaobin Wu retweeted
Replying to @xDaily
Back to spending 24/7 at work and sleeping in conference/server/factory rooms.
I must be super focused on 𝕏/xAI and Tesla (plus Starship launch next week), as we have critical technologies rolling out.
As evidenced by the 𝕏 uptime issues this week, major operational improvements need to be made. The failover redundancy should have worked, but did not.
Xiaobin Wu retweeted
Sounds enticing? Join us! Looking specifically for experienced C++/Rust backend engineers for grok.com and the API in the bay area: job-boards.greenhouse.io/xai…
The first interview only takes 15 minutes. Here are some of my retired questions for this role & interview:
- Assume you want to write your own string struct. What fields would you define on the struct?
- What are move semantics and why is moving a string faster than making a copy?
- Explain the differences between preemptive and cooperative concurrency.
- Where is the thread scheduler defined and when does it run?
- Why is iterating over an array faster than iterating over a linked list even though both operations are O(n)?
















