21 in 21

21 in 21: Calle on Cashu, Clawi, and AI Agents

On this episode of 21 in 21, Calle discusses his work on Cashu, Bitchat, and Clawi. He explores how AI agents could use bitcoin-native payments and why privacy-preserving infrastructure matters in an increasingly agentic internet. Calle also reflects on his journey down the bitcoin rabbit hole, from early work on Lightning infrastructure to building eCash systems, and shares his perspective on the evolution of AI agents. https://x.com/callebtc [https://x.com/callebtc] https://clawi.ai/ [https://clawi.ai/] https://bitchat.free/ [https://bitchat.free/] https://cashu.space/ [https://cashu.space/]

21 in 21: Linn Bieske on Hack-Nation and Building Global AI Communities

Linn Bieske, Co-Lead of the AI & Technology Track at the MIT Club of Northern California (CNC), AI Product Manager, and Co-Founder of Hack-Nation, joins Haley Berkoe on 21 in 21. They discuss the upcoming Hack-Nation event on April 25 and Spiral’s sponsored challenge exploring what becomes possible when AI agents can earn using the Lightning Network. Linn also shares her perspective on what motivates today’s AI builders, how to design experiences that lead to something more lasting than a 24-hour sprint, and why community and collaboration matter so much. Apply by April 19 to join the upcoming hackathon, or follow along for the next one. https://hack-nation.ai/ [https://hack-nation.ai/] https://www.linkedin.com/in/linn-bieske-189b9b138/ [https://www.linkedin.com/in/linn-bieske-189b9b138/] https://www.linkedin.com/company/hack-nation/ [https://www.linkedin.com/company/hack-nation/] https://www.linkedin.com/in/haleyberkoe/ [https://www.linkedin.com/in/haleyberkoe/] https://spiral.xyz/ [https://spiral.xyz/]

21 in 21: Rainey Reitman on Transaction Denied and Financial Censorship

Rainey Reitman joins 21 in 21 for a conversation on financial censorship, free speech, and her new book, Transaction Denied: Big Finance’s Power to Punish Speech. Rainey co-founded Freedom of the Press Foundation and serves on the board as president. She also spent 11 years at the Electronic Frontier Foundation, first as Activism Director and later as Chief Program Officer. Drawing on years of work in civil liberties advocacy, Rainey explains how lawful speech can still lead to frozen accounts, denied payments, and exclusion from the financial system. She also shares how these issues connect to journalism, whistleblowers, privacy, and Bitcoin’s promise, and limits, as a censorship-resistant tool. Links to Book: Amazon: https://a.co/d/04WK0Qek [https://a.co/d/04WK0Qek] Bookshop: https://bookshop.org/lists/transaction-denied-big-finance-s-power-to-punish-speech [https://bookshop.org/lists/transaction-denied-big-finance-s-power-to-punish-speech] Audio: https://www.audible.com/pd/Transaction-Denied-Audiobook/B0FJZRQXXR?source_code=AUDORWS0718179KY7 [https://www.audible.com/pd/Transaction-Denied-Audiobook/B0FJZRQXXR?source_code=AUDORWS0718179KY7] A portion of every book sale goes to support Freedom of the Press Foundation. [https://freedom.press/] “In her timely and necessary book, Reitman illuminates the shocking and widespread censorship exerted by the American banking system, details how Orwellian financial surveillance and control has become the norm, and makes a powerful case for why we must push for change if we want to preserve freedom and privacy in the 21st century.” — Alex Gladstein, Chief Strategy Officer, Human Rights Foundation Follow: https://x.com/RaineyReitman [https://x.com/RaineyReitman] https://x.com/FreedomofPress [https://x.com/FreedomofPress]

21 in 21: Michael Saylor on Bitcoin, AI, and Advice for Builders

Michael Saylor joined Haley Berkoe on 21 in 21 for a rapid-fire conversation on bitcoin, AI, and what’s coming next. He shares what’s top of mind for 2026, why he sees this year as a major turning point, and how he thinks bitcoin could evolve as digital capital beneath new layers of credit and currency. Then, Saylor gets into how AI will radically transform civilization, and how that shift could make bitcoin even more important in a world where autonomous agents need to transact constantly with digital capital. He points to Strategy’s use of AI in creating digital credit products like Stretch (STRC), and shares the kinds of bitcoin products he hopes to see, from deeper integration into everyday technology to applications powered by bitcoin. Saylor emphasizes that we’re entering one of the most fertile periods ever for building, and encourages builders and young people to spend a lot of time learning AI tools and continually pushing themselves to create something new and useful. There are also a few fun detours into MIT prank stories and the AI-generated X profile images he’s become known for. Follow: https://x.com/saylor [https://x.com/saylor] https://x.com/HBerkoe [https://x.com/HBerkoe] https://www.youtube.com/@PresidioBitcoin [https://www.youtube.com/@PresidioBitcoin] Links: https://www.michael.com [https://www.michael.com/] https://www.hope.com [https://www.hope.com/] https://www.uncute.com/products/here-comes-bitcoin [https://www.uncute.com/products/here-comes-bitcoin]

21 in 21: Andi Pitt on Bitcoin Venture, AI, and Cognitive Sovereignty

Andi Pitt of Ego Death Capital joined me on 21 in 21 to talk about the rise of new startups in the bitcoin ecosystem, how the funding landscape has changed, and the growing intersection of bitcoin and AI. She also shares what she looks for in founders and offers advice for launching a startup. Beyond venture, Andi discusses her recent research into mind control and cognitive sovereignty. Note: We recorded this while Andi was in town last November for the HRF AI for Individual Rights Summit. https://x.com/1andipitt [https://x.com/1andipitt] https://egodeath.capital/ [https://egodeath.capital/] https://clyrapassages.substack.com/ [https://clyrapassages.substack.com/]