Joined March 2014
33 Photos and videos
Pinned Tweet
22 Jul 2025
Excited to share that I've joined @aztecFND as Network Lead! I'll be working closely with validators and helping steward the governance process. I'll be retaining my role at @zkv_xyz to run validators on other networks. Grateful to be part of both missions!
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Jun 9
Last month we posted a large survey asking everyone that is running (or is interested in running) an @aztecnetwork sequencer about their experiences so far. Today we're posting the results of the survey, and are committing to improve the experience. forum.aztec.network/t/aztec-…
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May 28
More engineers are hacking again... They want to go to the lowest level and build their own version of the consumer products they use. AI is the driver. Deep tech (in this example think all the sensors Whoop has) is more accessible than ever, and shipping polished consumer UX on top of it has never been easier. @aztecnetwork is another perfect example. Not the easiest to use yet, but the bones are amazing. AI unlocked a wave of devs building real products on top of it.
Why hasn't anyone reverse engineered Whoop to work without subscription ?? It's just one /goal away
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Koen retweeted
Aztec Labs has acquired Obsidion, the team behind @ZKPassport. The Obsidion team will continue to develop ZKPassport while also leading new consumer product developments. The ZKPassport protocol will remain open source.
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Koen retweeted
Last week, @PrivacyEthereum asked 38 teams what's broken with private transfers on Ethereum. Every problem on the list has a solution currently live on Aztec. @mike_connor walks through each one, along with the implementation details. Read here: aztec.network/blog/10-privac…
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Koen retweeted
1/ We're thrilled to welcome @AztecFND as the latest project to take the 1% Pledge 🎉 1% of the AZTEC token supply has been deposited into Protocol Guild's 4-year vesting contract to support 187 Ethereum core contributors across client teams, research, and coordination
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May 12
It's become so easy to identify if texts are written by AI... and the volume of the things I read these days that is, is insane. 👨‍💻 I don't know how to feel about it. On the one hand it feels disingenuous and somewhat unprofessional. But then again... I do it, but gave the LLMs specific instructions on my writing style to make it feel more authentic. Is it OK / Acceptable that so many publications & technical write-ups are fully written by AI?
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May 11
Working with people who are **actually** want @aztecnetwork to succeed is so inspiring. I'm never the most motivated or smartest person in the room, we all push each other to achieve greatness. So many learning opportunities. Time to ship!⛴️⛴️⛴️⛴️⛴️
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Mar 30
Based on a conversation at EthCC today. Iykyk
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Mar 20
What companies are NOT using AI right now? The ones that don't are going to be left behind, and they are probably being pushed by shareholders / boards to start implementing it. But I hope that they don't go to expensive and (probably) mostly useless consultancy firms to ask for help implementing it. The engineers that get it, and that are effective at making organisational changes to get LLMs integrated (in an actually effective way) at every part of the org are going to do really well. The problem will be that some of these top level execs will see it as a one time integration into organisations. But the reality of this technology is that you need to be adapting all the time to new developments. The speed of new improvements is INSANE.
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Mar 19
Making sure Aztecs governance is as decentralised as possible has been one my main points of focus the last few months. We found consensus between all the contributors on how to discuss improvements to the Aztec Network, and how to go about proposing upgrades. Time to build 🏗️
Aztec is the first fully decentralized L2 on Ethereum. No privileged actors, no closed doors. Governance runs the same way. Any idea can become a protocol upgrade — if it survives public scrutiny. AZIPs, AZUPs, and onchain voting form a transparent pipeline from forum post to live protocol change. These are cypherpunk values in practice. Read about how it works and how to get involved: aztec.network/blog/how-aztec…
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Feb 27
I’ve been talking to people about AI strategies for the last few weeks (& to an extend months). The moment I saw Claude Code one shotting whole applications based on a product question, I knew announcements like this were inevitable. The power of coding is now in the hands of product people. The people who have deep knowledge of what users want out of the software that they’re managing. Those product people, having all the context about how users use the software can now (with AI coding) implement features (and fix bugs) at a much faster scale without relying on their dev teams. There definitely will still need to be quality control and sanity checks. Proper testing, good software practices and battle tested infrastructure designs are still weak points for AI. And that’s where engineers will still be required & will still shine. The next year is truly going to be interesting to watch. It AI tooling can keep the exponential improvements going, the software engineering landscape next year will look vastly different.
Feb 26
we're making @blocks smaller today. here's my note to the company. #### today we're making one of the hardest decisions in the history of our company: we're reducing our organization by nearly half, from over 10,000 people to just under 6,000. that means over 4,000 of you are being asked to leave or entering into consultation. i'll be straight about what's happening, why, and what it means for everyone. first off, if you're one of the people affected, you'll receive your salary for 20 weeks 1 week per year of tenure, equity vested through the end of may, 6 months of health care, your corporate devices, and $5,000 to put toward whatever you need to help you in this transition (if you’re outside the U.S. you’ll receive similar support but exact details are going to vary based on local requirements). i want you to know that before anything else. everyone will be notified today, whether you're being asked to leave, entering consultation, or asked to stay. we're not making this decision because we're in trouble. our business is strong. gross profit continues to grow, we continue to serve more and more customers, and profitability is improving. but something has changed. we're already seeing that the intelligence tools we’re creating and using, paired with smaller and flatter teams, are enabling a new way of working which fundamentally changes what it means to build and run a company. and that's accelerating rapidly. i had two options: cut gradually over months or years as this shift plays out, or be honest about where we are and act on it now. i chose the latter. repeated rounds of cuts are destructive to morale, to focus, and to the trust that customers and shareholders place in our ability to lead. i'd rather take a hard, clear action now and build from a position we believe in than manage a slow reduction of people toward the same outcome. a smaller company also gives us the space to grow our business the right way, on our own terms, instead of constantly reacting to market pressures. a decision at this scale carries risk. but so does standing still. we've done a full review to determine the roles and people we require to reliably grow the business from here, and we've pressure-tested those decisions from multiple angles. i accept that we may have gotten some of them wrong, and we've built in flexibility to account for that, and do the right thing for our customers. we're not going to just disappear people from slack and email and pretend they were never here. communication channels will stay open through thursday evening (pacific) so everyone can say goodbye properly, and share whatever you wish. i'll also be hosting a live video session to thank everyone at 3:35pm pacific. i know doing it this way might feel awkward. i'd rather it feel awkward and human than efficient and cold. to those of you leaving…i’m grateful for you, and i’m sorry to put you through this. you built what this company is today. that's a fact that i'll honor forever. this decision is not a reflection of what you contributed. you will be a great contributor to any organization going forward. to those staying…i made this decision, and i'll own it. what i'm asking of you is to build with me. we're going to build this company with intelligence at the core of everything we do. how we work, how we create, how we serve our customers. our customers will feel this shift too, and we're going to help them navigate it: towards a future where they can build their own features directly, composed of our capabilities and served through our interfaces. that's what i'm focused on now. expect a note from me tomorrow. jack
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Feb 22
Jim has been running decentralised infrastructure for longer than most people I know. His deep knowledge of how blockchains work and his well thought out opinions will be missed. He’s made some amazing contributions to the broader ecosystem and community. Over the past few years I’ve gotten to work with Jim across several projects, all of which seemed to get the same level of attention. I deeply appreciated his feedback and opinions around anything Aztec. He contributed massively by supporting Aztec through early sequencer testing, prover networks, public testnet participation, running a Genesis sequencer and supporting the creation of the slash veto council. My thoughts go out to his family & friends.
Friends, i have some terrible news. Jim Cousins (@jimwavefive) passed away earlier this week. A small number of his close friends, myself included, found out this evening. As did his family. I personally chatted with Jim more or less daily. He missed our usual biweekly call some days ago, and then didn't return my messages all week. He was always a focused, disciplined and super busy guy. But this silence was very out of character for him. As the days passed, I became increasingly worried for him. Today I reached out to others who had been feeling the same, and we arranged for someone to check on him. Jim was well-loved, widely respected, and deeply connected. I can only imagine there are others out there right now who are worried by his absence. While I know that some people may have preferred to give this some time, I believe Jim would have wanted to spare his friends the uncertainty. I’m not especially active here and I’m not part of every circle Jim built over the years. Please share this message in the hope that it reaches someone who has been left wondering, as i was. The truth hurts, a lot. But being left in the dark can hurt just as much.
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Feb 20
We're hiring @ the Aztec Foundation! Work with me to support the decentralised infrastructure operators! Offer support, help improve documentation and look out for their interests as important stakeholders in the @aztecnetwork ecosystem. aztecfoundation.bamboohr.com…
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Koen retweeted
$AZTEC is now live. This time next year, every smart contract will be private. Aztec was built for this moment. aztec.network/token
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Koen retweeted
25 Dec 2025
From Honk and the entire Aztec team, Merry Christmas and Happy Holidays 🎄
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Koen retweeted
11 Dec 2025
.@centrifuge @anemoycapital @SaharaAI & @aztecnetwork join @JillMalandrino on @Nasdaq #TradeTalks to discuss developing proactive AI policy that balances national security, consumer privacy, governance, and economics. x.com/i/broadcasts/1RDGlAqjN…

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21 Nov 2025
I'm here with the one and only @smpalladino until noon-ish! Swing by if you want to talk anything @aztecnetwork Ignition network or running a sequencer.
Getting everything set up at the @aztecnetwork booth for the last day of @EFDevcon. Last day to come say hi if you haven't yet!
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21 Nov 2025
Make privacy sexy again
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19 Nov 2025
Last night at 10PM UTC we hit 500 Genesis sequencers to stake their AZTEC to the Ignition Chain. 🎉 Thanks to all sequencers who beared with us through technical difficulties and last minute updates. My last 5 months at Aztec have gone into preparing for this moment!
19 Nov 2025
BREAKING: Aztec just shipped the Ignition Chain, the first fully decentralized L2 on Ethereum. This launches the decentralized consensus layer that powers the Aztec Network. ignition.aztec.network/ 🧵
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