Adam Nelson

@mattturck @yanndubs @OpenAI Awesome stuff!

Why AI Progress Suddenly Feels Real - my conversation with @yanndubs, who co-leads the Post-Training Frontiers team at @OpenAI 00:00 - Intro 01:30 - Why recent AI progress feels like a step function 04:13 - Model reliability & the emotional rollercoaster of shipping GPT-5.5 07:33 - How OpenAI structures vertical and horizontal teams 09:49 - Improving model efficiency and test-time compute 12:32 - Yann's journey from Switzerland to OpenAI 15:37 - Reasoning in 2026: Real-world utility vs verifiable rewards 18:34 - GPT-5.5 Thinking vs Pro: Scaling test-time compute 20:09 - How reasoning models become more efficient 23:23 - Pre-training scaling and overcoming the data wall 27:03 - Multimodal data, synthetic data, and embodied AI 31:05 - Demystifying mid-training and post-training 37:21 - Does RL create new capabilities in AI? 38:53 - The challenges and frontier of scaling RL 43:09 - Is building AI models a craft or a strict science 48:21 - How AI models generalize across different domains 54:18 - How reinforcement learning cures AI hallucinations 56:04 - Negative generalization and conflicting instructions 58:05 - Can RL scale to law, medicine, and the broader economy? 1:00:19 - The evaluation bottleneck and Model as a Judge 1:04:21 - Continuous AI progress & continual learning 1:08:49 - Will foundation models eat the agent harness 1:11:23 - Why startups should focus on the last mile of AI

We're thrilled to welcome @arjundundoo to FirstMark as our newest Investor focused on the consumer tech landscape! Prior to joining us, Arjun was at Bird (NYSE: BRDS), where he helped lead M&A and capital markets. FirstMark has a long history in consumer (Pinterest, Airbnb, DraftKings, Ro, Function Health, Discord, etc.), so we couldn't be more excited to have Arjun joining the team, as we double down on backing and supporting the next generation of iconic consumer businesses. Please join us in giving him a warm welcome 🚀

@davidrgoldberg @alpacavc congrats on a great run! excited to see what's next

🦙UPDATE🦙 After 12 incredible years cofounding and building @alpacavc , earlier this year I informed my partners I would not be raising/investing Fund IV with them. I am incredibly grateful for this time and the great work we did. 4 Venture Funds + 1 RE fund, couple hundred million $ invested into some of the most inspiring founders I've come across. But even more grateful for the learnings and the relationships. A special thank you to the founders (and LPs) that put their trust in me and the team. Not quite leaving just yet…I’ll be transitioning to a Board Partner, working even harder with our current portolio founders, remaining on my Boards. Will be passing the torch to @aubriepagano for future VC funds, who will lead Alpaca’s next phase. Outside of my work at Alpaca, I'll be spending time in a couple areas: 1) Angel Investing 2) Leveraging my access and network for select growth deals and secondaries 3) Building a portfolio of local (Miami!) cash flowing businesses...first one closing soon 🍞 If any of these interest you, please don't hesitate to reach out!

Yesterday, 150+ AI CEOs gathered in NYC for AI✦NY — an off-the-record summit focused on the most critical challenges defining this moment in AI. We heard from @akofoid (Databricks), @c_valenzuelab (Runway), @kareemamin (Clay), @AmandaKahlow (1mind), Rob Chisholm (Qatalyst) Kunal Madhok (Wells Fargo), Amin Venjara (ADP), and Tom Haslam (KPMG). Co-hosted by @amishjani (FirstMark), and @NeerajVC (Battery), with moderators @abimbhet, @billbinch, @BrandonGleklen, and Scott Goering. Special thanks to @FifthThird @golub @KPMG @CooleyLLP @googlecloud, and @qatalystgroup!

The biggest winner of the neobank takeover is @raincards. From $100 in processed volume in April 2023 to $300,000,000 in April 2026. One of the biggest & underrated growth stories in crypto.

a dayy in the life: episode 9 ft. @cnaut from @raincards we made it rain (payy cards) in the rain office. full episode coming soon™

Speaking at FirstMark's Guilds Summit on June 16 in NYC: Cofounder & CEO, Datadag CEO, Tubi Chief People Officer, Airbnb CFO, Legora Chief Data & AI Officer, Snowflake Head of People, Clay CFO, Shopify Chief Product Officer, Okta Head of Americas, Enterprise, Anthropic Cofounder & CTO, Braze VP Sales, Vercel CMO, Bilt Rewards CFO, Ramp COO, Harvey CFO, Circle CRO, Synthesia Cofounder & CPO, Wealthsimple CFO, Runway Chief People Officer, Headway Cofounder & CTO, Factory Head of Product, Glean CRO, Brex CFO, Mercury Chief People Officer, HungryRoot VP, Global People & Places, Airwallex + more to be announced!

Public blockchains are great for auditability but different use cases need different levels of confidentiality. Now Rain customers have a choice. Today we're announcing our integration with @payy_link bringing configurable on-chain privacy to Rain's stablecoin card programs. Payy Network uses ZK cryptography to keep transaction details private by default, with selective disclosure for compliance and transaction monitoring. @sidgandhi_xyz @calummoore and the @payy_link team were early Rain customers and proved out the tech and demand themselves. Now we're making it available to everyone else.

Build on Payy Network with @privy → Embedded wallets out of the box → Auth, sign, and send stablecoins natively → EVM-compatible, minimal config Private transactions chain meets 🤝 seamless onboarding.

Last year we proved onchain privacy can work for 80K KYC’d users with the Payy Visa Card. Now for the first time we’re bringing that capability to EVERY Rain card program. That’s millions of cards and billions of dollars in real world stablecoin spending. Incredible push by both teams on this and we couldn’t be more excited.

Love seeing these two awesome @FirstMark co’s come together t bring the promise of stablecoins to the institutional use cases that make up the meat of the market. Just the beginning cc: @sidgandhi_xyz @calummoore @rooqster @cnaut

@harris Are there other kinds? Must be missing those

Don't bring numbers to a vibes pitch

Our founder @sidgandhi_xyz sits down with @adamn to talk about why we chose @FirstMarkCap as our investor.

@jalehr Love it!!! Congratulations!

We raised $72M from Sequoia/YC and hit 8-figures in ARR. Then we shut it all down & rebuilt the company from scratch. Today we’re launching the new Mutiny: the first AI agent for GTM teams to create anything customer-facing, in minutes. Comment "Mutiny" to get 3X free credits.

Congratulations to @vercel @ClickHouseDB and @WeAreLegora for making the ET30 — a list of the most promising private companies in enterprise technology, from @Wing_VC and @EricNewcomer 👏

I chose @FirstMarkCap to lead our recent round because they have the confidence and conviction to back and grow generational startups across every vertical. Every company using ACH and SWIFT today, will be defaulting to stablecoins in a few years. But what blockchain will they use? They will choose one that is built from the ground up for safety, security and privacy. These principles have motivated me across my career starting with my time at Apple. Now we’ve instilled this philosophy into Payy’s products and technology. Some of the largest stablecoin infra providers are partnering with us to finally enable default confidential payments on EVM — never before achieved. I’m incredibly excited for this next chapter of Payy supported by @FirstMarkCap, @robotventures, @dba_xyz and all our other investors.