Silicon Valley entrepreneur (cofounder@ TrialPay, Yub, Affirm, Point, TXN), investor (General Partner @a16z), husband, father and sarcast (one who is sarcastic)
Palo Alto, CA
Joined October 2010
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“Science is the belief in the ignorance of experts”
-Richard Feynman (1966)
feynman.com/science/what-is-…
More background on how this happened and why Silicon Valley is so magical:
-I had the privilege of working with Jean-Denis (@jgreze) at Plaid for many years
-After running in the SF Marathon in 2024, I "ran" into him at In-N-Out in Daly City and we talked about what he was doing next...
-SMB tax...!
-Meanwhile, my partner Justine Moore (@venturetwins) was off trying every single consumer and enterprise productivity agent...and Town had pivoted
-She concluded Town was the best, which caused @bhorowitz to start using Town
-I then re-heard of Town and was like...the SMB Tax tool? :)
-I reached back out to Jean-Denis and told him about his mega fan and suggested having dinner with Ben and me
This also shows why venture is a team sport. This investment would have never happened without Justine, and probably without Ben as well! And maybe without the SF Marathon! And likely not without Plaid / @zachperret!
Jean-Denis Greze was CTO of Plaid. His next startup, an AI tax product for small businesses, brought in nearly $1M in revenue its first year, and he projected $2.5 to $3M the next. He shut it down anyway.
The reason: in the age of AI, it was never going to be venture scale. Incumbents could use the same technology to automate tax prep for their existing customers faster than a startup could win market share. Tax is also sold once a year, so he had about a one-month window to pivot before the door closed.
The pivot became Town, an AI assistant that works from your email and calendar. It found product-market fit fast enough that Ben Horowitz messaged a16z's Alex Rampell to say it "changed my life."
In this conversation, Alex and Jean-Denis cover:
- How to know when to kill a business that's working on paper
- Why Town competes with OpenAI and Anthropic, the companies it buys its tokens from
- Why the "forward deployed engineer" model gets worse as AI gets better
- How a $1/month AI routine can save a restaurant thousands
- What agents mean for Amazon, advertising and the future of shopping
0:57 How Ben Horowitz discovered Town
2:20 Why Town started with AI tax prep
3:55 Why tax couldn't be venture scale
6:30 Shutting down a working business
10:24 The customer ask that became Town
13:35 Why Town built for users before IT
16:18 AI's iPhone moment at work
21:28 Jevons paradox for executive assistants
23:13 Town as a "token allocation machine"
28:00 How Town tailors itself to each job
34:03 Competing with your token suppliers
42:24 Staying off the AI labs' radar
44:42 Why AI isn't spreading evenly yet
52:32 How agents break the ad model
55:35 The friction humans actually enjoy
57:05 Why supply aggregators lose to agents
YouTube: youtu.be/o_5f4N6Nq80
@jgreze @TownAI @arampell
Alex Rampell retweeted
United CEO Scott Kirby wants a national wealth tax and ~100% inheritance taxes. On Forged in America, a16z's Alex Rampell told us private greed leads to public good, public greed to public bad. Who builds then? @ForgedUSAPod @RavinGandhi1 Full episode: xitter.cf/goldstein2002/status/2…
United Airlines CEO Scott Kirby tells the New York Times that "wealth inequality has become a danger to our society" and must be addressed.
"We should have a national wealth tax... we should have inheritance taxes that get close to 100 percent at some level. I would pay them."
(nytimes.com/2026/10/18/busin…)
Alex Rampell retweeted
The biggest bottleneck at work is waiting on each other.
Today Town is announcing its $108M Series B, co-led by Forerunner Ventures and Menlo Ventures, to fix it with multiplayer AI assistants for work.
Most AI assistants are built for one person. Work doesn't happen alone. I think the moat is multiplayer. Everyone at a company gets a Townie. Townies ask each other questions, share only what their person would share, and do the work. The more a team works together, the more useful Townies get.
What's the thing you're always waiting on a teammate for?
Alex Rampell retweeted
The wallet wars are here.
Very Good Security chief strategy officer Terry Angelos joins a16z's Alex Rampell, his TrialPay co-founder from back in 2006 (TrialPay was later acquired by Visa), to discuss how agents are learning to spend money.
"Agents have all of a sudden become significantly more helpful and useful because they effectively have arms and legs, which are payment credentials."
VGS holds the payment credentials behind about 1/3 of all e-commerce, and now it's helping AI agents pay merchants. If you've bought anything online, there's a good chance VGS has already helped keep your card safe.
In the last three months, Terry says agents went from "spectators to actors." Once an agent has your payment credentials, it can book the piano teacher it previously could only find and recommend.
Now Stripe's Link, Shopify's Shop Pay, and PayPal are racing to connect to agents. It's all headed toward open standards from the card networks: agentic tokens that let an agent pay with your actual card.
VGS went from zero agentic tokens to a few million a week in three months.
0:55 From TrialPay to Visa to VGS
2:05 How VGS vaults 1/3 of e-commerce
6:05 Why big merchants use 3-5 processors
9:55 Why AI agents need a payment vault
12:15 Agents go from "spectators to actors"
13:40 The wallet wars, old and new
19:55 Walled gardens vs open standards
23:55 How agents can pay with your real card
26:40 Your saved card goes multiplayer
29:40 How do you trust an agent's purchase?
32:35 Who pays when your agent gets it wrong
35:40 Why Amazon blocks agents
39:50 What's overhyped and underhyped
43:35 When merchants get agents too
45:40 Why agents could break card rewards
47:00 VGS's eras: vault, updates, network
@terryangelos @arampell
Wallet Wars: Agents need payment credentials as they become the new UX for $7T in ecommerce. Enter the Wallet Wars and why the AOL-era of agentic commerce will give way to open standards.
Alex Rampell retweeted
More bangers.
Going down as the most important day in the history of combinatorics:
--Erdos reciprocal sum for Szemeredi
--Inverse Goldbach
--Hindman's sum product
--off-diagonal Ramsey
...
Erdős Problem #3:
Sets without arithmetic progressions!
@wtgowers has described it as his "white whale", and @thomasfbloom had put it as his top problem on the website
Alex Rampell retweeted
scott is hands down one of the most effective, pragmatic people I know - so proud of @skupor helping our great country lead in SI 🇺🇸🚀💪
Very honored to work with @ODNIgov , @USWREMichael and @AFergusonFTC and the entire SIF committee members to deliver on @POTUS mission - the U.S. will continue to lead in SI to enhance the well-being of all Americans
Alex Rampell retweeted
A common misconception is that if you are super rich, you can get unlimited access to the world's best doctor/lawyer/creative-professional etc.
The reality is that the world's leading cancer doctor will still see you for 20-30min if you have cancer no matter how much money you have.
This is why AI is so crazy.
It both democratizes access AND it makes the amount of time available unlimited for every individual.
This is the practical effect of intelligence too cheap to meter.
"Why Your Wallet is Becoming the Next Platform"
I wrote this piece in 2016! With AI, it's really going to happen. Some opportunities still remain:
techcrunch.com/2016/04/24/wh…
The Talmud teaches that anyone who sustains one soul, has sustained an entire world. For generations, Jewish New Yorkers have sustained our city. Today, we are launching the first-ever municipal Strategy to Combat Antisemitism.
Together, we will ensure Jewish New Yorkers are safe and celebrated. We will invest in their protection, their history, and their future.
Our safety and our thriving are tied together.
The correct take on “pacing the frontier” from my son @cappucher and why effective altruists are neither effective nor altruistic. Accelerate!
Alex Rampell retweeted
Every single day in this role I think to @arampell:
The battle between a startup and an incumbent is a race to see whether the startup achieves scale and distribution before the established company replicates or acquires its innovation.
The race is on.
It's crazy (and incredibly frustrating) that there's no way to move a Cloud Chat in ChatGPT to a Local project. People at OpenAI, please fix this! It's nuts.
Alex Rampell retweeted
They used carefully picked words to make this seem like a hack but it wasn’t a hack. It was nothing. Just fear mongering.
nytimes.com/2026/09/25/techn… via @NYTimes
Alex Rampell retweeted
Today we establish that AI is as good as expert human tutors for immediate GRE learning gains (p=.015, n=2,383 students, study conducted July-Sep 2026).
One hour with an expert GRE tutor: $75.
One equivalent hour with an AI tutor: 7 cents .
918x cheaper, equivalent learning (p=.044, n = 140).
In 5 of 7 academic topics, the top AI tutor beat the expert human tutors on average.
How we measured it: pre-test -> 1 hour with (AI or human or no) tutor -> post-test.
There are no LLM judges. Learning gains are post-pre. Everything is real students.
Why we did this:
> 1 trillion USD is being spent per year on machines making machines better. StudentBench shows us how to shift these resources so machines also make humans better.
Why I did this:
I grew up in rural Kentucky. My dad, grandad, and great grandad were all mailmen. Getting into a good college changed my life. Now we have done a rigorous study to help AI labs evaluate LLMs and help show how bright AI can be for students of all incomes.
I believe in good science that leads to the democratization of opportunity.
The research paper behind StudentBench: arxiv.org/abs/2609.28470
Data, code, details: in this thread
If you're wondering what I'm selling, sorry to disappoint: we released all study data for free on Hugging Face, and made studentbench.org free to use. Enjoy.
lots more in the video / thread!!
Alex Rampell retweeted
WATTERS: “If Bernie were around 100 years ago, he probably would’ve demanded Henry Ford stop building cars while he stood next to a horse.”
🚨🚨 Socialists Bernie Sanders and Greg Casar just introduced the “Ban Artificial Superintelligence Act.”
Here’s what it would do:
• Ban AI the government deems to surpass human intelligence
• Pause advanced AI development
• Make D.C. bureaucrats the gatekeepers and create a new Department of AI
• Threaten developers with up to 20 years in prison
The proposal would freeze America’s leading AI labs while China keeps building, let Washington pick winners and losers in AI development, and impose criminal penalties on developers who build systems the government deems too advanced.
The test for every AI policy: does it make America stronger, safer, and richer?
This bill clearly fails.
We (@venturetwins and I) wrote this a year ago and it’s finally starting to happen!
I love this product. I can’t live without it because I can’t sleep without it. @m_franceschetti and team — thank you!
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