Casado: a16z's conversation with Tutor Intelligence

Martin Casado promised "you'll learn something from this." He called it "one of the more in depth discussions I've ever had on end to end economics of robotics," including why robotics companies tend to verticalize and how hard the long tail is @martin_casado. In the a16z episode, Casado and Raghu Raghuram talk with Tutor co-founder and CEO Josh Gruenstein. Topics include going from a first sales call to a working robot in about three months, and why so many robot startups died building for a single customer @a16z. Tutor charges by the hour with no upfront cost. When the AI gets stuck, a human "tutor" takes over, which creates training data @a16z. YouTube @a16z

Tan, Lütke, Casado: "Weight-Space Programming"

Three investors and founders shared Rikiya Takehi's post. In it, GPT-6 Astra edited Qwen3.5-0.8B's weights directly. It changed 0.016% of them and, according to the post, improved math up to 6x and instruction following 3x, with no gradients or training @rikiyatakehi. Takehi calls this "Weight-Space Programming" (blog) @rikiyatakehi.

• Garry Tan called it an "Interesting new use of smaller models" @garrytan.
• Tobi Lütke: "this is exactly as crazy as it seems" @tobi.
• Casado shared Alex Krentsel's reproduction of the results. Krentsel calls it a step-change capability that has appeared only in the latest models @AlexKrentsel. Casado asked whether it "must be an artifact of efforts to do RSI within the labs" @martin_casado.

Masad: Replit's security advisory on AI agents

Amjad Masad promoted @lhchavez's "Security advisory: Make managed cloud environments the default for AI agents." His framing: agents running on employee machines are becoming "a systemic security risk." He noted that Goldman Sachs has reportedly restricted tools like Claude Code @amasad. The advisory points to supply-chain attacks and prompt injection hidden in GitHub issues or emails. It argues that agents' broad privileges make them attractive targets @lhchavez. Replit's recommendation is to run agents by default in managed, isolated cloud environments. Credentials, permissions, network access and production changes would stay outside the agent's reach @lhchavez.

Modal's CEO: Seven Powers and Ben Thompson's "gingerbread man" post

On 20VC, Modal co-founder and CEO Eric called Hamilton Helmer's Seven Powers "a good book" for thinking about moats. He warned that founders read it and "get delusional," when "you never have moats in the early days" 20VC with Harry Stebbings. The post he says he "always come[s] back to" is a Ben Thompson piece on Snap's "gingerbread man" strategy. Snap had no moat, so it just ran faster, and he thinks that holds "for almost every startup these days" 20VC with Harry Stebbings. Episode

Shaan Puri: Die with Zero

Shaan Puri posted notes from time with Bill Perkins, author of Die with Zero. He admits he missed the book's main point the first time: it is about dying with zero regrets, not zero dollars @ShaanVP. He calls it a "Top 5 book title," arguing that the same ideas sold as "live life to the fullest" would be forgettable @ShaanVP. Full episode @ShaanVP

Alexandr Wang: Wildwood

Alexandr Wang called Wildwood "a true marvel of human artistry, craftsmanship, and storytelling." He said he liked it even more than You Can See Everything @alexandr_wang. He noticed that it, like Hoppers, treats death as natural and inevitable @alexandr_wang. He also pointed to a Buddhist/Taoist theme of non-intervention: trying to impose our own ideas of goodness on the world can do harm @alexandr_wang. "Huge fan, go see it!" @alexandr_wang Post

Shorter picks

• Sarah Guo shared Colossus's Michael Kratsios profile, calling it a look at "important behind the scenes work" by "a civil servant who understands technology" @saranormous. Harry Lambert wrote the piece @colossusmag. Patrick O'Shaughnessy had already shared it.
• Tobi Lütke shared MLStreetTalk's clip "What if there is no hard problem?" with Joscha Bach (@Plinz) @MLStreetTalk. He called interviews with Joscha "the most fascinating podcasts" and Bach "one of the few modern real philosophers" @tobi.
• Vinod Khosla shared "Going founder mode on cancer," about GitLab co-founder Sid Sijbrandij (@sytses). He calls it "An extraordinary story of agency" @vkhosla.
• Michael Seibel said he wanted to clip a podcast where Sequoia's Doug Leone called finding product-market fit "a dark art" that investors can't help with, and put it in YC's Bookface and user manual. His point: product-market fit is "your responsibility" Dalton + Michael.