Bitcoin Takeover Podcast

We recorded this at Bitcoin Amsterdam, the Bitcoin Magazine conference, with legendary cypherpunk and Satoshi contributor Martti Malmi. This is his second time on the show. Two years ago in Prague we talked about 2009, the forum, and the man who signed his emails Satoshi Nakamoto. This time I had promised we would talk about what he is building now. The conference still put him on a history panel.

Martti would rather talk about Iris, the Nostr client at iris.to, and especially NostrVPN, which he describes as Tailscale without the Tailscale company: your devices find each other on Nostr, with no email login and no coordination server. Underneath is FIPS, an ad-hoc mesh routing protocol. He also walks through Iris Chat, Iris Drive, git.iris.to, Hashtree, and a directory of about 20 apps at apps.iris.to. He is not making money from any of it, and he does not think software is a great business model anymore. Finnish people, he says, tend to be a bit ideological and not great businessmen. Maybe he is the same way.

We talk about Nostr in a bear market, about building for AI agents versus building for humans, and about permissionlessness as the reason an agent might pick Nostr at all. I put my usual heresy to him, that Bitcoin is now a family of projects, and he stays open-minded: if network effects dissolve, funds may gravitate to the best store of value and the best way to pay, and the biggest network may matter less. For him, Bitcoin is still mostly a store of value. He would like to tap to pay and not have to tell the merchant he wants to pay in Bitcoin.

We do break the "no Satoshi" rule twice. Martti is the one who set bitcoin.org up on WordPress, and he still thinks the man who struggled with that setup was "just a guy," unless you prefer the joke that the integer overflow bug was planted to make a time-travelling AI look human. And he remembers Satoshi paying him for the website work in US dollars, in an envelope, sent to his father's address so it would not sit on a dorm floor. He does not have the original envelope. His grandfather, in 2009, thought this could become a global reserve currency, and did not buy any. Years later, after another crash headline, his father messaged him: "I hope you sold early." And he did.

In between there is the year he stopped writing code himself, "meat agents" in smart glasses, a romantic argument that the best life extension technology is having kids, Michael Pollan on simulated feeling, and a fifty-percent kind of optimism about permissionless tech. You can find him on Nostr as Sirius, at iris.to/sirius. The name comes from the pun, the star, and Sirius Black.

What we cover:

Why history panels still haunt him, and why he wanted to shill the new work

NostrVPN as a peer-to-peer Tailscale alternative, and FIPS mesh routing

Iris Chat, Iris Drive, git.iris.to, Hashtree, and the apps.iris.to directory

Why he is not trying to make money from software

Nostr's chicken-and-egg problem, bots, and a bet on agentic use

Whether we are building for humans or for agents

Bitcoin as a family of projects, and dissolving network effects

Payments, Lightning, Square, BTCPay, and tap to pay

The bitcoin.org WordPress story, and "oh, he's just a guy"

The year he wrote no code, longevity, and consciousness

Satoshi, an envelope of dollars, and "I hope you sold early"

How to find him: Sirius, iris.to/sirius, and the three links to try first

This episode is sponsored by SideShift, Cake Wallet, eCash / LayerTwo Labs, Braiins Hashpower, and Orange Rock.

The previous conversation is S16 E12: Martti Malmi on Bitcoin in 2009 & Satoshi Nakamoto, at bitcoin-takeover.com/s16-e12-martti-malmi-on-bitcoin-in-2009-satoshi-nakamoto/. His published correspondence with Satoshi is at mmalmi.github.io/satoshi/. The full Bitcoin Takeover archive is at bitcoin-takeover.com.

Timestamps

0:00 Intro

0:47 Welcome: Martti at Bitcoin Amsterdam

1:52 The history panel he would rather skip

3:06 How Nostr brought him back

3:54 NostrVPN: Tailscale without the company

5:19 Coordination servers and a Mac Mini

7:51 GPT-6 Astra and seven Codex subscriptions

9:40 Iris Chat, Iris Drive and 20 other apps

10:35 Software is no longer a business model

12:14 What listeners should try

15:35 Vlad's Nostr problem: same names, more bots

17:42 Bullish on Nostr in a bear market

18:31 Building for agents, or for humans?

20:00 Permissionlessness

20:45 Bitcoin as a family of projects

23:09 When network effects dissolve

25:20 Sponsors: SideShift, Cake Wallet, eCash, Braiins Hashpower, Orange Rock

32:16 Self-custody and payments that just work

37:10 Store of value, Square and BTCPay

38:21 Lightning, iPhones and tap to pay

40:14 Human slop and a website rebuilt with AI

41:57 He set up bitcoin.org's WordPress

43:17 The year he wrote no code

45:33 A romantic on longevity

48:00 Copies, consciousness and Michael Pollan

49:22 Bitcoin, GPUs and the AI power story

52:27 Talking to agents more than to people

54:26 Making things is easy. Getting anyone to care is not

57:53 Kids leaving university, and Movie Maker

1:01:02 Is he still optimistic about Bitcoin?

1:02:49 The next bull market: agents with wallets

1:03:19 Satoshi sent dollars in an envelope

1:05:23 "I hope you sold early"

1:07:53 Recap: NostrVPN, Iris Chat and the other apps

1:09:38 Fifty percent optimistic

1:10:37 Sirius Black and the brightest star

1:12:45 Thank you and goodbye

We recorded this conversation in Mexico, at an undisclosed location, during the celebrations for Zcash's 10th anniversary. Daira-Emma Hopwood has been with the project for 11 years, since before launch, and came to it through Zooko and the Tahoe-LAFS community. Daira-Emma reviewed the code for the 2016 ceremony and designed the ceremony protocol, later co-authored the Halo paper with Sean Bowe and Jack Grigg, which led to Orchard and Halo 2 without a trusted setup, and has been a strong voice for Zcash Shielded Assets (ZSAs). Today Daira-Emma is Head of Research and Assurance at ZODL, the Zcash Open Development Lab, which the former Electric Coin Company staff started the day after they handed in their notice.

On the table next to us was the ceremony laptop we bought from Peter Todd: the keyboard, the motherboard burned with a blowtorch, and the discs that held the software and the transcript. Daira explains what went wrong with Sprout: the flaw was not the ceremony itself but the BCTV14 proof system, whose setup put values in the transcript that were not necessary and could have leaked the toxic waste.

From there we go through the codebase Zcash inherited from Bitcoin Core 0.11.2 and why Daira-Emma is relieved that zcashd is no longer a consensus node on the network, the Equihash parameter mistake that brought ASICs in sooner and pushed GPU hobbyists out, and why Daira-Emma designs for the long term instead of trusting today's mining pool distribution.

The second hour gets more personal and more political. Daira-Emma declares an interest as a founder who received part of the founders reward, defends the Dev Fund and the ZCG grant slice, and explains why the coin-weighted poll should not, in Daira-Emma's view, override the rest of the community, both on grants and on ZSAs. The conversation covers harassment on X, why sex workers were a constituency Daira-Emma had in mind when joining Zcash, and the call for crypto to fix its credibility problem with the left.

We close on AI: how the Orchard vulnerability was found by a person using a publicly released model, how ZODL switched Orchard off within 48 hours, the worry about developer burnout and upgrades every few months, and why understanding what we build is not optional.

What we cover:

Where Daira was during the 2016 ceremony, and the Sprout counterfeiting bug inherited from BCTV14

Halo and the move to Orchard and Halo 2 without a trusted setup

Designing an MPC ceremony with very little Bitcoin experience

Moving from zcashd's C++ to Zebra and Rust, and why precise specs help AI check implementations

Block times, NU7 and propagating zk-SNARK transactions

What Daira-Emma would change before launch: the Equihash parameters

Crosslink, objective finality and partitioning attacks

Removing the transparent side and private by default addresses

The end of ECC and the start of ZODL

Monero, ring signatures and competition between privacy protocols

Network privacy: Tor, Nym, Dandelion++ and multisig for hardware wallets

The ZCG grant controversy, ZSAs and coin-weighted polls

AI, the Orchard vulnerability, post-quantum work and assurance

This episode is sponsored by Cake Wallet, SideShift, Orange Rock, eCash and Braiins Hashpower.

The full archive of the Bitcoin Takeover podcast, with every season and every transcript we have published, is at bitcoin-takeover.com.

Timestamps

0:00 Intro

0:45 Welcome: Zcash's 10th anniversary in Mexico

1:34 Where Daira was during the 2016 ceremony

2:31 The Sprout counterfeiting bug and where it came from

3:29 Halo: getting rid of the trusted setup

4:31 Zooko, Sean Bowe, Daira: dropouts or not?

5:32 Hands-on with the destroyed ceremony laptop

7:57 Designing the ceremony with little Bitcoin experience

10:35 What's good and bad about Bitcoin Core's codebase

12:15 From C++ to Rust: how different is Zcash today?

14:35 Block time, issuance and propagating big zk-SNARKs

16:56 Sponsors: Cake Wallet, SideShift, Orange Rock

18:24 What Daira would change in Zcash before launch

21:15 Crosslink: hybrid proof of work and proof of stake

25:33 Mining centralization: Foundry, China, hostile governments

27:06 Sponsors: eCash, Braiins Hashpower

29:00 Why Daira stayed with Zcash for 10 years

32:42 Projects built on Zcash cryptography

36:38 Removing the transparent side: private by default?

39:22 ECC dissolves, ZODL is born

45:11 Dandelion++, Tor and network-level privacy

47:57 VPNs, censorship and Iran

49:30 Hardware wallet hacks and self-custody setups

54:21 Slush, Trezor and Zooko

55:11 Any regrets about money?

55:35 The ZCG controversy and sex workers

1:05:27 Dealing with online harassment

1:09:37 Ironwood and Hopwood: who picked the name?

1:10:57 Zcash Shielded Assets (ZSAs): worth it?

1:23:20 Will Bitcoin ever adopt Zcash-style privacy?

1:25:17 Move fast and break things?

1:27:44 Why Zcash keeps its cypherpunk developers

1:30:50 Zcash 10 years from now

1:32:43 Daira's inventions and inspiration in cryptography

1:39:42 What gets Daira out of bed

1:41:31 AI, podcasts and training data

1:46:47 AI and the Orchard vulnerability

1:55:11 Head of Research and Assurance at ZODL

1:57:15 AI vs. training apprentices

1:59:35 Music, books and Zcash upgrade names

2:01:08 Amber, the Zcash color

2:01:58 Anything we missed?

2:03:48 Thank you and goodbye

Kris Nuttycombe of the Zcash Open Development Lab came back to the show two years after his first visit, this time on a hotel sofa at Zcon7 in Cancun, on the last day of the conference and around Zcash's tenth birthday.

We cover the price move and the Binance hack that was unfolding while we spoke, Zcash as what Bitcoin could have been, hard forks as a superpower, the end of Sprout and the inflation bug, Ironwood and formal verification, Crosslink and hybrid proof of work, ZIP 318 and Tachyon, the Dev Fund and Zcash Community Grants, the Equihash ASIC extinction event, and why ossification is death.

Timestamps

0:00 Intro & sponsors

2:09 Kris's second appearance

2:51 ZEC from $38 to $1,250

3:57 Zcon vs Bitcoin conferences

6:29 Privacy for refugees

7:42 NU7 & 25-second blocks

9:04 Why Zcash matters to Bitcoiners

12:12 Satoshi & zero-knowledge proofs

13:57 Hard forks as a superpower

19:32 Fungible internet money

21:56 Zcon7 impressions

24:27 ZEC flips Dogecoin

27:37 NEAR Intents & privacy at rest

30:33 Paying Visa merchants with shielded ZEC

33:43 A pluralism of currencies

34:19 Cake Wallet & Zcash Names

36:39 Unified addresses rant

41:35 The ceremony laptop & Zooko's CPU

42:06 Kris's story: Zooko & Tahoe-LAFS

44:22 Is Zooko Satoshi?

48:59 Sprout and the inflation bug

53:38 26,000 unclaimed ZEC

55:38 Q-Day & lost coins

59:21 Ironwood & formal verification with AI

1:03:31 The eCash hard fork

1:04:14 Dandelion++ & positive-sum thinking

1:07:04 Bitcoin dominance at 60%

1:09:10 Stablecoins are wrapped fiat

1:15:45 Are Zcash miners being phased out?

1:16:27 Crosslink: hybrid PoW/PoS

1:20:23 Kris's work at ZODL

1:22:25 ZIP 318 & Tachyon

1:25:26 Why Kris stayed with Zcash

1:29:39 Can Zcash ossify?

1:33:59 The currency of AI

1:40:23 Bitcoin layer 2s

1:42:10 Ossification is death

1:43:36 Saylor, covenants & 2106

1:46:57 Day two: Zebend

1:49:15 Zcash Community Grants & the Dev Fund

1:50:52 The Equihash ASIC "extinction event"

1:54:00 Security is not a market

1:58:12 Hashrate distribution

2:00:33 Proof of work & the labor theory of value

2:04:54 Hashrate as a finality gadget

2:06:25 Friendly forks & testnets

2:09:53 All value is social

2:12:31 Death by a thousand forks?

2:17:12 What if Zcash forked Bitcoin?

2:19:13 Zcash's next 10 years

2:21:44 Seed phrases & BIP39

2:23:14 AI made software cheap

This episode was recorded while driving to BitDevs in Atlanta. The car belongs to Art (at least 1/3 of it) and is the first vehicle ever bought for bitcoin in 2013: a 2011 Toyota Prius, for which the Mycelium wallet founder paid 1000 BTC.

We talk about cars, Bitcoin development, why the medium of exchange side of BTC matters, and how we can achieve privacy and scalability. Other people join too towards the end: Ekrem Bal from Citrea, Christian from Alpen Labs, Paul Sztorc from LayerTwo Labs, and Rob Hamilton from Anchor Watch.

Timestamps

0:45 Riding to the BitDevs barbecue in the 1,000 BTC Prius

2:05 The first car ever bought with bitcoin

11:29 Robin's 1,000 BTC dream car: a VW Beetle?

16:01 BitPay, KYC and why BTCPay Server exists

29:50 Would you pay 1,000 BTC? Shielded CSV vs Visa

32:54 Roger Ver and the block size war revisited

38:01 TABConf highlights: Peter Todd, Paul Sztorc and a 2029 cleanup

45:27 LayerTwo Labs, BIP300 and drivechains

49:31 Cake Wallet, Wasabi and the Spark custody problem

57:30 Arriving at BitDevs: the Taproot annex PR

1:01:09 Ekrem of Citrea and the Bitcoin privacy wars

1:06:24 Bitcoin Spaces and one name for every address

1:10:15 Alpen vs Citrea, then Paul Sztorc joins

1:16:10 BitNames and the Truthcoin relaunch

The second day of TABConf 8, live from Atlanta. Ekrem Bal talks Citrea privacy, Kevin Loaec explains Liana wallet, Spaces Protocol introduces BTC handles, Bitcoin credit unions enter the scene, Peter Todd unboxes his Zcash ceremony laptop 10 years later.

Timestamps

0:00 Stream warm-up

2:29 Ekrem Bal: Citrea pivots to privacy with Crest

7:22 Privacy and scalability on Citrea

11:30 Privacy as protection from physical attacks

16:00 Lessons from almost a year on mainnet

19:00 User feedback and the Clementine web app

20:13 Alpen, garbled circuits and Clementine v2

21:33 Next use cases: lending, vaults and agent spending limits

22:51 Making Citrea post-quantum

26:21 Great Script Restoration and trust assumptions

29:29 OP_CAT vs CTV vs template hash

31:26 How Crest differs from Tornado Cash

33:12 Railgun and proof of innocence

33:53 Why build on Bitcoin instead of Ethereum

36:23 Favorite fork: Taproot and Zcash envy

38:19 The eCash replay trick

41:24 Skiing and mountaineering

42:51 110 BTC on Citrea

43:34 Kevin Loaec joins

44:31 First and last TABConf and the unconference format

46:21 A bad year: Coldcard, Liquid and Liana

48:00 Stu joins

48:41 Vaults vs Liana’s timelocks

51:59 Most interesting guest and 10 hour episodes

54:02 Forks magazine

55:32 Script emulation on Bark

56:08 Liana videos and Revault

57:32 Favorite covenant and enforced amounts

59:40 Wrench attacks and Liana’s exposure

1:01:07 Ledger leaks and buying hardware online

1:03:41 Coldcard’s RNG bug, license and bounties

1:06:07 Andrew joins: Spaces Protocol

1:10:30 Buffer joins

1:10:55 3,700 spaces and @bitcoin handles

1:11:18 The TABConf name giveaway and delegation

1:14:39 Nacho and payment handles

1:15:39 Burning @tabconf forever

1:17:45 32 bytes on chain and cert relays

1:19:15 Client-side validation and censorship resistance

1:20:18 One click install on StartOS

1:21:14 How Spaces makes money

1:22:17 What stops an alt Spaces?

1:24:01 Namecoin, squatters and 10 auctions a day

1:27:25 Utility: Nacho and social proofs

1:29:37 Don’t reuse your name address: silent payments

1:32:19 Spaces and Bitcoin’s scalability

1:33:39 Do names expire?

1:35:43 One character names

1:37:10 Insight gateways, Nostr and Blossom

1:40:43 The Fabric resolver

1:41:23 Handle pricing

1:44:02 Where to learn more about Spaces

1:47:00 Spaces and the forks

1:53:44 Last call for @tabconf handles

1:55:42 Goodbye Andrew and Buffer

1:57:34 Hallway break

2:00:00 Kevin Loaec returns: Paris, Sparrow and Miniscript

2:05:26 Funding open source without begging users

2:12:33 A horrible year: hacks and forks

2:13:47 Bitcoin follows the crowd

2:28:55 New guest and matching watches

2:29:57 What makes you bullish about Bitcoin?

2:31:05 Closing hallway chatter

2:43:10 Part 2: Back online: The Bitcoin Pivot and the three C’s

2:47:39 How credit unions will custody bitcoin

2:49:28 An advisory firm with vendor-agnostic partners

2:51:47 Why TABConf is welcoming

2:52:26 Feedback and the wave of credit union mergers

2:56:32 Credit unions vs banks: the not-for-profit mission

2:58:32 Lightning and paying with Bitcoin

2:59:10 Credit unions as Lightning service providers

3:00:22 Rehypothecation risk and Aave

3:01:39 NCUA, not FDIC

3:02:07 Where to learn more about The Bitcoin Pivot

3:02:52 Peter Todd arrives and the stream pauses