Pinned Tweet
Hey everyone, some personal news I’m really excited about...
For the past few months I’ve been working on a book proposal with my friend and colleague Tim Sullivan (@Tim_Org). We’re excited to share that it’s just been acquired by Crown Currency at Penguin Random House!
We’re side The Machine: How Computer Science Rewired Everything.
Most of us talk about tech in terms of the shiny stuff — apps, gadgets, platforms, and the people who built them. But this misses a bigger, more interesting story.
Computer science didn't just hand us new tools. It changed how we think about problems in the first place — what even counts as a problem, what looks like a solution, what we optimize for, and what we ignore.
Over time, this way of thinking has seeped outward and saturated everything else. You see it in markets that run like algorithms instead of human institutions, in media that’s tuned for engagement, in companies organized more like software than trad hierarchies. Even in the way people talk: inputs, outputs, signals, noise, etc.
Once you start noticing it, it’s hard to stop seeing it everywhere.
Tim and I have spent years separately reporting on tech, business, science, and economics, and then also as editors on the a16z crypto editorial team. Throughout, we kept running into the same big question: what happens when the logic of computing becomes the logic of society?
This book is our personal attempt to answer that — to trace how these ideas spread (often without us realizing) and how they’ve reshaped the systems we all live with, including the tradeoffs that come with them.
We’re still super early in the process, but we’re thrilled it’s happening. If you want to follow along as the book comes together, we’d love that.
In the meantime, tell us: what’s your favorite example you’ve seen of computer science thinking sneaking into everyday life? Could be in business, politics, dating, whatever — we'd love to know what you all notice.
For the past few months I’ve been working on a book proposal with my friend and colleague Tim Sullivan (@Tim_Org). We’re excited to share that it’s just been acquired by Crown Currency at Penguin Random House!
We’re side The Machine: How Computer Science Rewired Everything.
Most of us talk about tech in terms of the shiny stuff — apps, gadgets, platforms, and the people who built them. But this misses a bigger, more interesting story.
Computer science didn't just hand us new tools. It changed how we think about problems in the first place — what even counts as a problem, what looks like a solution, what we optimize for, and what we ignore.
Over time, this way of thinking has seeped outward and saturated everything else. You see it in markets that run like algorithms instead of human institutions, in media that’s tuned for engagement, in companies organized more like software than trad hierarchies. Even in the way people talk: inputs, outputs, signals, noise, etc.
Once you start noticing it, it’s hard to stop seeing it everywhere.
Tim and I have spent years separately reporting on tech, business, science, and economics, and then also as editors on the a16z crypto editorial team. Throughout, we kept running into the same big question: what happens when the logic of computing becomes the logic of society?
This book is our personal attempt to answer that — to trace how these ideas spread (often without us realizing) and how they’ve reshaped the systems we all live with, including the tradeoffs that come with them.
We’re still super early in the process, but we’re thrilled it’s happening. If you want to follow along as the book comes together, we’d love that.
In the meantime, tell us: what’s your favorite example you’ve seen of computer science thinking sneaking into everyday life? Could be in business, politics, dating, whatever — we'd love to know what you all notice.
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have the people who lament crashing attention spans considered that a lot of things aren't worth paying attention to
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join us!
I am hiring a social media lead for a16z Frontier!! “We’re lucky enough to be living through one of the most consequential curves in human history today” — THIS is the time, come work with us now! ⚡️🔑🔭💥🗺️
a16z.com/about/jobs/?gh…
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Few people embody the builder ethos more than @alive_, across body, mind, and code.
Can’t wait to see what he creates.
Can’t wait to see what he creates.
Big personal news today: I have decided to leave @a16z, move to SF, and start a company.
It's time to build :)
It has been almost 10 years since I joined the firm. I met @cdixon, @bhorowitz, and @pmarca in 2017. At the time, I was an engineer at Google Brain working on robotics. I had a deep interest in open source. I knew nothing about investing. Chris meanwhile had already planted the @a16z flag at the frontier that was early crypto with investments in companies like Coinbase. But the crypto team at the firm consisted of only him, and he had the ambition to expand. His pitch to me was simple: "You should leave Google and come help me build the crypto vertical at the firm."
The work we've done together since then to build out our team and support our founders has been the most meaningful work of my life. I am grateful to have spent a decade working with everyone here, supporting our founders, learning from Chris, Ben, and Marc, and living the firm's culture. It is a culture that values integrity, life-long working relationships, and the belief that we humans have the power to build our own future.
Marc and Ben have built a16z into an incredible force for good in the world.
Before I joined the firm, I always thought that my inevitable path was to become a founder. The truth is that I wasn't ready for it then. Somehow, this year I've gotten the overwhelming feeling that this has changed.
As for what I want to build: It is early, but I care most about building infrastructure that enables open software ecosystems. I am starting with two core observations:
1. AI today is largely a single-player technology. Most uses involve one human talking with one agent in isolation from the rest of the world. That will soon change. Most uses of AI will soon be many-to-many: many humans and many agents working together. There will be at least one massive open network on top of which those uses will be built.
2. Software is now free. It can now be written just-in-time, on the spot for a single individual's hyper-targeted use case, and it can even be thrown out after a single use. This means that our entire software stack will have to change. In the limit, it will lead to a whole new kind of AI-mediated operating systems, which in turn will create an ecosystem of AI-native developers who build applications that actively rebuild themselves on the fly.
If you are working on related ideas, and especially if you are in the Bay Area, hit me up. Let's chat!
@bhorowitz , @pmarca, @cdixon, @eddylazzarin, @guywuolletjr, @jasonrosenthal , and our whole team — I want to thank you. Working with you has been the time of a lifetime. I am forever an a16z superfan and your ally.
Onward 🫡
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Robert Hackett retweeted
A few reflections on the lattice vs. hash-only debate that our recent Aerie post sparked:
1. Cryptographic ossification for blockchains was never safe. Until the day we know with certainty that P ≠ NP, that finding short vectors in lattices is intractable, that Keccak effectively behaves like a random oracle in deployed SNARKs, and that every single bug has been eliminated from our codebases, blockchains cannot ossify. That is simply not how safe systems are built. Issues will arise, and the system will have to respond.
It’s a double standard to reject lattices because blockchains are hard to upgrade if lattices break, while counting on upgrades if AI breaks your hash function or finds a critical zkVM bug.
The best counterargument is that hash-only designs are more agile: if your hash function breaks, just swap out the hash. But we must aspire to a higher level of agility than this. Indeed, as I cover next, if SNARK recursion itself turns out to degrade security, the proposed hash-only blockchain designs would need to be rethought from the ground up.
2. The real security debate is not lattices vs. hashes — it is lattices vs. building everything on SNARK recursion. That’s because “hash-only” is not really hash-only: it rests on hashes plus the soundness of deep SNARK recursion. Ethereum’s roadmap relies on exactly that: hash-based aggregation needs recursion to keep up with a slot’s worth of signatures, and EIP-8288 would send other signature schemes and users’ own proofs through the same recursive pipeline. In contrast, Aerie proves a slot’s worth of signatures on one laptop without any recursion.
All deployed post-quantum SNARKs rely on the Random Oracle Methodology (via Fiat–Shamir) to establish their security. This is an idealization we know fails in the real world: we have explicit counterexamples where “SNARKs” coming out of this methodology are totally insecure when instantiated with any concrete hash function.
We generally ignore these counterexamples in part because they only arise when proving contrived, self-referential statements about the very hash function used by the SNARK verifier.
But proving statements about the verifier’s own hash function is the exact thing you do in SNARK recursion. That’s why the security of recursive SNARKs can’t be established even in the random oracle model.
On top of that, the standard security proofs for recursion (in other models) suffer an “extractor runtime” blowup that is exponential in the recursion depth, suggesting that security may degrade as more recursion is applied. Yet Ethereum’s own EIP-8288 enables unlimited-depth recursion, even as it lists soundness of recursive SNARKs as a trust assumption. Proofs in more idealized models avoid the blowup, but they mainly tell us that an attack on SNARK recursion would have to exploit the concrete hash function, which is exactly what the Fiat–Shamir attacks above do.
To be clear, we don’t know of any outright attacks on SNARK recursion, and I very much hope it is secure. But some of us who have studied the question have a lingering sense that an attack may be possible in some settings. And if AI is going to supercharge cryptanalysis, there is no reason to expect it to spare Fiat–Shamir for SNARKs, let alone SNARK recursion, both of which have had far less scrutiny than lattices.
So, I do not concede that a “recursion everywhere” hash-only approach is clearly more conservative than one built on standard lattice assumptions.
3. “Just wrap everything in a hash-based SNARK” (like EIP-8288) faces challenges.
Aggregating signatures and proofs off-chain into a single block-level proof is a powerful design independent of the hash-only vs. lattice debate, and I am not telling people to avoid it. But claiming, as Vitalik Buterin did this week, that users can run whatever cryptography they want locally and wrap it in a client-side leanVM proof glosses over major hurdles.
For example, leanVM today is a minimal VM designed almost entirely to prove hash-based signatures and recursion, not general-purpose computation. And binary-field SNARKs like leanVM remain slow at proving the integer multiplications that lattice cryptography does en masse.
I am optimistic that many of these zkVM challenges can be met (including via my own work, binary-field Twist and Shout, which are now implemented in Magnetar). But regardless, if lattices can make aggregation simpler and faster, then they should be leveraged. We need to be agile no matter what.
4. For chains whose reason for existence is privacy, I truly struggle to understand the pushback. Public-key encryption (and fast single-server PIR) cannot be built from hashes alone, at least not in any black-box way. If lattices break, it is going to be very, very hard for these chains to provide acceptable levels of privacy and functionality. For a project whose entire reason for existence is privacy, a loss of confidentiality is an existential failure. Next to that, a second signature upgrade (after the first one, from elliptic curves alone to, hopefully, a hybrid lattice scheme) is easy.
Summary: We don’t know for sure what is secure and what isn’t. We are all weighing unquantifiable risks against each other, and we do not need to agree on a total order on them. But hash-only solutions face many open engineering challenges, and they are not more “conservative” in the way some have argued. Some of those challenges are entirely prosaic and have nothing to do with bugs or cryptography, like hardware support for custom schemes whose hash function is still undecided. I hope we can overcome those challenges within the appropriate timelines, but they must be acknowledged and portrayed realistically.
Overall, cryptographic agility and defense in depth (e.g., hybrid signatures) are the answer, which is why we are building both lattice-Jolt and hash-Jolt. In practice, the positions are less polarized than social media discourse suggests: for example, StarkWare is working to make Falcon verification cheap (falcon.provably.fast), which is great to see.
Here is the (apparently) controversial take I am sticking to: Conditioned on agility, whenever lattices make systems simpler or more functional, we should embrace them rather than default to “hash-only” designs. Lattices are what the rest of the world will depend on, with decades of study and hardening behind them, and at the system level, less functional often means less secure. Where hash-only designs are just as simple and functional, by all means use them.
1. Cryptographic ossification for blockchains was never safe. Until the day we know with certainty that P ≠ NP, that finding short vectors in lattices is intractable, that Keccak effectively behaves like a random oracle in deployed SNARKs, and that every single bug has been eliminated from our codebases, blockchains cannot ossify. That is simply not how safe systems are built. Issues will arise, and the system will have to respond.
It’s a double standard to reject lattices because blockchains are hard to upgrade if lattices break, while counting on upgrades if AI breaks your hash function or finds a critical zkVM bug.
The best counterargument is that hash-only designs are more agile: if your hash function breaks, just swap out the hash. But we must aspire to a higher level of agility than this. Indeed, as I cover next, if SNARK recursion itself turns out to degrade security, the proposed hash-only blockchain designs would need to be rethought from the ground up.
2. The real security debate is not lattices vs. hashes — it is lattices vs. building everything on SNARK recursion. That’s because “hash-only” is not really hash-only: it rests on hashes plus the soundness of deep SNARK recursion. Ethereum’s roadmap relies on exactly that: hash-based aggregation needs recursion to keep up with a slot’s worth of signatures, and EIP-8288 would send other signature schemes and users’ own proofs through the same recursive pipeline. In contrast, Aerie proves a slot’s worth of signatures on one laptop without any recursion.
All deployed post-quantum SNARKs rely on the Random Oracle Methodology (via Fiat–Shamir) to establish their security. This is an idealization we know fails in the real world: we have explicit counterexamples where “SNARKs” coming out of this methodology are totally insecure when instantiated with any concrete hash function.
We generally ignore these counterexamples in part because they only arise when proving contrived, self-referential statements about the very hash function used by the SNARK verifier.
But proving statements about the verifier’s own hash function is the exact thing you do in SNARK recursion. That’s why the security of recursive SNARKs can’t be established even in the random oracle model.
On top of that, the standard security proofs for recursion (in other models) suffer an “extractor runtime” blowup that is exponential in the recursion depth, suggesting that security may degrade as more recursion is applied. Yet Ethereum’s own EIP-8288 enables unlimited-depth recursion, even as it lists soundness of recursive SNARKs as a trust assumption. Proofs in more idealized models avoid the blowup, but they mainly tell us that an attack on SNARK recursion would have to exploit the concrete hash function, which is exactly what the Fiat–Shamir attacks above do.
To be clear, we don’t know of any outright attacks on SNARK recursion, and I very much hope it is secure. But some of us who have studied the question have a lingering sense that an attack may be possible in some settings. And if AI is going to supercharge cryptanalysis, there is no reason to expect it to spare Fiat–Shamir for SNARKs, let alone SNARK recursion, both of which have had far less scrutiny than lattices.
So, I do not concede that a “recursion everywhere” hash-only approach is clearly more conservative than one built on standard lattice assumptions.
3. “Just wrap everything in a hash-based SNARK” (like EIP-8288) faces challenges.
Aggregating signatures and proofs off-chain into a single block-level proof is a powerful design independent of the hash-only vs. lattice debate, and I am not telling people to avoid it. But claiming, as Vitalik Buterin did this week, that users can run whatever cryptography they want locally and wrap it in a client-side leanVM proof glosses over major hurdles.
For example, leanVM today is a minimal VM designed almost entirely to prove hash-based signatures and recursion, not general-purpose computation. And binary-field SNARKs like leanVM remain slow at proving the integer multiplications that lattice cryptography does en masse.
I am optimistic that many of these zkVM challenges can be met (including via my own work, binary-field Twist and Shout, which are now implemented in Magnetar). But regardless, if lattices can make aggregation simpler and faster, then they should be leveraged. We need to be agile no matter what.
4. For chains whose reason for existence is privacy, I truly struggle to understand the pushback. Public-key encryption (and fast single-server PIR) cannot be built from hashes alone, at least not in any black-box way. If lattices break, it is going to be very, very hard for these chains to provide acceptable levels of privacy and functionality. For a project whose entire reason for existence is privacy, a loss of confidentiality is an existential failure. Next to that, a second signature upgrade (after the first one, from elliptic curves alone to, hopefully, a hybrid lattice scheme) is easy.
Summary: We don’t know for sure what is secure and what isn’t. We are all weighing unquantifiable risks against each other, and we do not need to agree on a total order on them. But hash-only solutions face many open engineering challenges, and they are not more “conservative” in the way some have argued. Some of those challenges are entirely prosaic and have nothing to do with bugs or cryptography, like hardware support for custom schemes whose hash function is still undecided. I hope we can overcome those challenges within the appropriate timelines, but they must be acknowledged and portrayed realistically.
Overall, cryptographic agility and defense in depth (e.g., hybrid signatures) are the answer, which is why we are building both lattice-Jolt and hash-Jolt. In practice, the positions are less polarized than social media discourse suggests: for example, StarkWare is working to make Falcon verification cheap (falcon.provably.fast), which is great to see.
Here is the (apparently) controversial take I am sticking to: Conditioned on agility, whenever lattices make systems simpler or more functional, we should embrace them rather than default to “hash-only” designs. Lattices are what the rest of the world will depend on, with decades of study and hardening behind them, and at the system level, less functional often means less secure. Where hash-only designs are just as simple and functional, by all means use them.
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Robert Hackett retweeted
under-appreciated nuance
9/ But here, lattices remove the need for recursion and custom hash-based signatures, making the system simpler and less brittle. That concrete benefit has to be weighed against the far more speculative possibility of new attacks on standard lattice assumptions.
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Robert Hackett retweeted
1/ Today we’re releasing Aerie: fast post-quantum signature aggregation, using lattice-based SNARKs for lattice-based Falcon signatures. On a laptop (CPU only), it aggregates roughly a full Ethereum slot’s worth of signatures (32,768) in 0.65 seconds.
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one of the clearest signs that stablecoins have product-market fit is that usage keeps growing despite the broader crypto markets usual mood swings.
shared some thoughts on this in @AlliumLabs's latest stablecoins report.
shared some thoughts on this in @AlliumLabs's latest stablecoins report.
Our Q3 State of Stablecoins & Payments report is live.
9 months of onchain data. 15+ industry perspectives, including Visa, Stripe, Coinbase, Citizens, Stellar, Moody's Ratings and more.
From stablecoin supply to payments, cards and AI agents.
Download the full report: allium.so/reports/state-…
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forward-deployed philanthropy
harden the planet
harden the planet
Small cities, school districts and rural hospitals guard our most sensitive data with the fewest resources to defend it.
Today we’re launching Securing America’s Infrastructure Foundation, a new nonprofit, bringing AI-powered cyber defense to them at no cost.
SAIF starts with focused goals for on the ground impact and $25M in committed funding by a16z's founders. I’m joined by a founding board of Brian Barrios, @GoldsmithOnGov, Bob Lord, @vishalmisra and @philvenables.
If you lead a small city, rural school district or hospital system or want to join our team, please reach out: info@secureourinfra.org
Read our full announcement here: a16z.news/p/introducing-…
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Robert Hackett retweeted
A masterclass in what to do when AI tears up the rules your business was built on.
Your games are being decompiled and run on hardware you don’t sell. You can call the lawyers. Or you can start a lab and embrace it.
x.com/asha_shar/stat…
Your games are being decompiled and run on hardware you don’t sell. You can call the lawyers. Or you can start a lab and embrace it.
x.com/asha_shar/stat…
Today we're standing up XBOX LABS (labs.xbox.com). Here is the note that I sent to the team:
Team,
The first video games emerged some 75 years ago. In the time since, there have been booms and busts, but every year there are more great games to play, more devices to play them, and best of all, more people than ever playing. That growth helped make XBOX what it is today, and we've helped shape the industry in return, from bringing hard drives to consoles and online gaming through Xbox Live to Game Pass and cloud gaming, alongside franchises that have brought millions of people together.
In recent weeks, we've seen games rapidly decompiled and rebuilt to run on hardware they were never originally designed to support. Windows PC builds have been translated to run on Apple Silicon or ported to run inside a browser through WebAssembly and WebGPU, the latter now approaching 90% global browser support. Perhaps more surprisingly, we've seen many of the biggest games in the world have been remixed into the source code of another.
These experiments challenge long-held assumptions about our industry: the tether between software and hardware, the boundary between creation and play, and how people discover and experience games. While it is hard to predict the future of gaming, it is easy to see the possibilities in making great games easier to access, giving old games new life and allowing more players to become creators and co-creators. These are unmistakably good outcomes for players, even when (and sometimes because) they challenge our existing business models.
To explore these possibilities, I’ve asked Scott to stand-up XBOX LABS, a small group of game makers, engineers and scientists whose job is to turn emerging ideas into things our players and developers can experience. We'll build in the open, learn from what people do, and measure success by whether more people are playing and creating.
I think XBOX has an important role to play here. Coding became the first major workload for agents because they can write, run, and test software. Games share many of those same properties, and people spend more than 72 billion hours a year playing XBOX games, roughly five times the estimated time spent writing code worldwide. We've spent 25 years learning how to make great games, and I want our game makers to help shape what these new technologies make possible. As we learn, we’ll share the tools we build with developers across the industry, just as we always have.
Our priorities aren't changing. We remain committed to the 4Cs, to making great games, to our hardware and to being responsible stewards of IP and the communities built around it. LABS gives us a way to explore new technology that is game design led without abandoning the work already underway.
Asha
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Robert Hackett retweeted
One of the core challenges that traditional financial institutions face when growing adoption of their crypto-related products has been the ability to reach KYCed customers who want to purchase these products. However, onchain KYC itself has not fully been solved.
I did a deep dive of current onchain KYC solutions, along with corresponding regulatory frameworks, alongside my @a16zcrypto partner @MicheleKorver. We also discuss the forthcoming Know Your Agent (KYA) landscape and emerging solutions.
I did a deep dive of current onchain KYC solutions, along with corresponding regulatory frameworks, alongside my @a16zcrypto partner @MicheleKorver. We also discuss the forthcoming Know Your Agent (KYA) landscape and emerging solutions.
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goodreads would be more useful if it purely logged ‘at what speed did i listen to this book’
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Robert Hackett retweeted
Informative discussion by very knowledgeable experts about the threat to modern cryptography posed by AI models. The good news is that the models can vet cryptosystems much faster than the human mathematicians we've relied on in the past, building trust and allowing more rapid deployment.
AI is getting better at solving hard math problems, especially given recent drops. But what does that mean for the cryptography that protects everything from private messages to healthcare to banking and crypto wallets?
Stanford cryptographer Dan Boneh, with @eddylazzarin, vy, and @smc90, makes sense of the warnings sounded recently. They cover:
- what’s fact vs. assumption
- what’s new and what risks cryptographers have long prepared for
- where quantum computing doesn't (and does) fit
- opportunities for builders
Highlights:
00:37 – What sparked the most recent debate about AI and cryptography
01:35 – Signal vs. noise: What the math does and doesn’t tell us
05:29 – Why cryptography depends on open problems
09:25 – Why the stakes go beyond blockchains
10:43 – How AI could strengthen confidence in cryptography
13:50 – Considerations for users and institutions
20:10 – Where AI and quantum threats overlap
22:32 – Building systems that can change cryptographic methods
23:59 – Hash-based versus lattice-based cryptography
33:07 – Opportunities for builders, and better security tools
38:14 – What comes next if there were a cryptographic break?
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had my first magical experience using @bot to plan a 2-night getaway.
i was on the phone with a human for an hour and got nowhere.
grok figured everything out and did all the points optimizing stuff i neither like nor want to do in just a few minutes.
true beauty.
i was on the phone with a human for an hour and got nowhere.
grok figured everything out and did all the points optimizing stuff i neither like nor want to do in just a few minutes.
true beauty.
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Robert Hackett retweeted
This podcast from @a16zcrypto includes an aspect that hasn't been stressed enough. In the end, AI cryptanalysis is a great thing for cryptography as it helps us gain confidence in new assumptions, key sizes (e.g. for new PQ schemes) and more. youtube.com/watch?v=k_CoOo…
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