TFTC: A Bitcoin Podcast - #741: Solving The Wrench Attack with Max Guise

Episode Date: April 29, 2026

Marty sits down with Max from BitKey to discuss the evolution of Bitcoin self-custody, the launch of the new seedless hardware wallet, and the architectural challenges of making Bitcoin "everyday money." Max on X: https://x.com/max_guise STACK SATS hat: https://tftcmerch.io/ Our newsletter: https://www.tftc.io/bitcoin-brief/ TFTC Elite (Ad-free & Discord): https://www.tftc.io/#/portal/signup/ Discord: https://discord.gg/yHGkvYxdqT Opportunity Cost Extension: https://www.opportunitycost.app/ Shoutout to our sponsors: Bitkey https://bitkey.world/ Aven https://www.aven.com/bitcoin CrowdHealth https://www.joincrowdhealth.com/tftc Unchained https://unchained.com/tftc/ Salt of the Earth: https://drinksote.com/tftc Join the TFTC Movement: Main YT Channel https://www.youtube.com/c/TFTC21/videos Clips YT Channel https://www.youtube.com/channel/UCUQcW3jxfQfEUS8kqR5pJtQ Website https://tftc.io/ Newsletter tftc.io/bitcoin-brief/ Twitter https://twitter.com/tftc21 Instagram https://www.instagram.com/tftc.io/ Nostr https://primal.net/tftc Follow Marty Bent: Twitter https://twitter.com/martybent Nostr https://primal.net/martybent Newsletter https://tftc.io/martys-bent/ Podcast https://www.tftc.io/tag/podcasts/

you've had a dynamic where money's become freer than free if you talk about a fed just gone nuts all all the central banks going nuts so it's all acting like safe haven i believe that in a world where central bankers are tripping over themselves to devalue their currency bitcoin wins in the world of fiat currencies bitcoin is the victor i mean that's part of the bull case for Bitcoin. If you're not paying attention, you probably should be. Max, it's great to be here with you. Yeah, thanks for having me. Thanks for coming. We've got the new BitKey in my hand. Awesome. We just set it up. And I think a lot of people are going to be extremely happy with what you guys put together. I think based off our conversation, our ongoing

conversations over the last year, I think we should start from the beginning, the hard, really hone in on the hard problems of self-custody and how you guys have approached that design problem as it pertains to bitcoin self-custody because not your keys not your coins obviously it's been a mean for uh well over a decade at this point but for many people the sort of jumping over the hurdle of taking other coins off an exchange onto a hardware wallet it's a no-go for them there's too many sort of hurdles seed phrases having the hardware while thinking about how to secure it and this is the design problem you guys have been focused on so from first principles how do you guys approach self-custody yeah it's almost exactly as you

described right up front which is about the hardest problems in self-custody and so the way we think about this is we want people to be able to own their own coins and we know there are a lot of barriers to that. We know there are a lot of problems that they might not be able to solve themselves and for which they want and need great tools that make it really easy to get the right security, recovery, and privacy properties. And so we started looking at this as kind of that holistic problem right when we started developing BitKey. And we started with a really long list of things that we wanted to solve. And I think everybody knows you can't solve everything at once. And so we tried to hone in on what is it that's really in most people's way. And for us,

The very first answer to that was really about recovery and ease. It was about safety, safety and ease of use. And what we were finding is that lots of people were turned away from self-pestity because, you know, the beginning of the process is a really long list of instructions. The setup process takes a while. Things are very technical, and people were being sort of left having to protect a seed phrase that maybe they didn't fully understand and sort of had to go on an odyssey to design their own wallet.

And I think, you know, anyone who's familiar with ITKI knows that we spent a lot of time trying to think about how to how to solve that and what we brought to market was basically a comprehensive set of recovery tools we really focused on that first and we got you know the first big key hardware out there the first big key recovery system out there there a lot of people start using it and then one of the ways we work is we start listening to what our customers have to say and figuring out what was our vision of the next hardest problems right and what we found was lots of the things that we were thinking about our customers were

thinking about, too. And one of the next ones that we took on was privacy. So at some point, we should probably dig into some of the improvements we've made there. So one of the things that typically happens with systems that protect Bitcoin and soft custody systems in particular is that you have to make a trade off. Maybe you get really good recovery properties or maybe you get really good security properties. But especially if it's like a collaborative custody system that integrates hardware and software, a lot of times that means giving up privacy, like maybe giving a third key in a two or three multisig up to another company that's going to be there and support you when you lose parts of your wallet. And that comes with a privacy

trade-off. That company can see your wallet, your balance, all the transactions that you've made in the past and future. And that's a trade-off that I think had been largely accepted. And we spent some time working on that problem, figuring out how can we make it better so that you can lean on a custodian exactly when you'd like to, or lean on a self-custody system or a collaborative custodian exactly when you'd like to, but maybe not have to give up all that privacy. And then what we're talking about today, and I think what you can see was one of the next biggest problems that we wanted to solve is coming back around to, in a system that does all of those things, adding additional on-device verification for transactions, transaction

parameters, but not just some of those conventional things that are verified on screens and other solutions, but also like critical account security properties, like emails associated with your account, SMS associated with your account, that sort of thing. And so what we're looking at with the newest BitKey is, you know, the same ease of use, the same seedless sovereignty, the same private multi-sig, but with on-device verification. I think this was the biggest point of feedback of the old BitKey that I always got is there's no screen. Like I need to be able to verify the receive address or the send address and i think you guys did an incredible job of answering that question of like when when screen and if so how i mean it takes up the full bottom of the wallet

and uh it's funny we were going through the onboarding process of this and i was using it like an old bit key like looking at it this way and you're telling me like no there's a whole new ux you need to look at the screen and you put your finger on the back so there's a new way of interacting with this ergonomically, which I like. One of the things I think is part of our core part of our development process is we do user research. So we sit down with customers, potential customers. We watch people use the devices that we make.

We watch people use the software that we make. And that heavily informed the choices we made in like the send flow and some of the things that you'll see when you're sending from that device. And then what you were just describing is actually something that we're currently adding some additional things to kind of help people use the new device in a way that's a little bit different.

If you're an existing customer, you may have enrolled your thumb as a fingerprint on it, be tapping on the stone side of the device. There's a little bit different flow with the new device. And then people who are brand new to BitKey, what we've found is whenever they're using the device, they go straight for that. And so we paid a little bit of attention in our design process to what it looks like to upgrade from our first BitKey to the second BitKey. And so there's a whole flow dedicated to that that kind of walks you through how to do that safely, especially if you're holding a lot of Bitcoin on BitKey.

Yeah. Well, speaking of new BitKey owners, that's actually one thing I'm curious to get some insight in from you is with the old BitKey even. I mean, again, radical changes to the traditional approach to hardware wallets, no seed phrase. You've got this collaborative custody between the hardware wallet, the mobile app and blocks server in the cloud. And a lot of Bitcoiners that have been around for a while are like, oh, this is completely new, this is completely far. But based off of all the user research that you've done and interviews that you've done, how have people that have gone from never having a hardware wallet to going straight to BitKey, what are some of the main responses they give when you ask why BitKey? Yeah, I think by far and away the first thing I'd highlight is the onboarding time.

So the time from unboxing BitKey, either this one or the first BitKey, is very short. And, you know, minutes. Minutes from opening the box to making your first Bitcoin transaction. And that's something that we thought needed to be a core part of this. The door into self-custody should be incredibly easy. And so we spent a lot of time optimizing that in the first BitKey. And I think what we saw is that process alone brought a lot of new people into self-custom. We saw people choosing it because now is the time for them to take the plunge. We saw people buying five, ten plus bit keys and gifting them to others and saying to that person that they've been talking about getting off the exchange with,

there's finally something that you can use to do this. And I love that every time we see it. And so we saw a lot of that. And then something that we also saw and that is definitely part of what led to our latest and newest BitKey is that we also saw a lot of Bitcoiners using it. People who had held Bitcoin for a really long time, familiar with a lot of other products, had already, they knew the value of self-custody. They'd set it up themselves. Frankly, they'd taken a lot of pain in doing so over many years, especially people who'd been in for a long time. And we found that they love BitKey too.

And so we started hearing from, especially that part of our customer set, that they'd love to have a screen and have that option on BitKey to do this kind of on-device verification. And so we really saw a bunch of different people using BitKey, which is one of the things that every time we launch a product, we get surprised by some of the things people do with it. And it's always awesome to see that here. What are some of the non-obvious pitfalls, edge cases, or design decisions that most people are probably unaware of when it comes to designing a hardware wallet, let alone one like the one that you guys are putting out? I think the thing I'd highlight here is that the set of things that can happen to people when they're self-custodying their coins is unbelievably large. Like maybe you lose your phone and you lose your hardware. I'll use that as an example. So you lose both.

That one's not unintuitive, but a lot of people, when they're first looking at BitKey, they wonder what happens if I lose my phone or what happens if I lose my hardware, and there are very easy answers to those questions in our system. But then they start to get to things like, what if I lose both?

And we have a recovery contact solution for that. They get to questions like, what happens if Block goes out of business and isn't making BitKey anymore? And we have our emergency exit kit for that. And we had to go through all of these different cases of, well, what if somebody lost their phone and then they click these buttons,

and then they got a new device, and they started onboarding, but they didn't finish it. And then they pick it back up later. And the team has spent so much time looking closely at making all of those flows really robust and accounting for all those cases to make sure that this just works. Like in all the cases where you could lose things,

you get a new phone with different app versions, different firmware versions. We've covered so much that it's... I think that task is really kind of the invisible complexity under the hood. And the way I think about that is when we take on complexity and we and we sort of hide it from customers and they don't have to deal with it. And that's that's what a tool is for. And that's what it is. I mean, this is about one ingredient to everything you guys are doing across the whole block family of companies dedicated to that. I mean, every company within

block is dedicated to Bitcoin in one way or another. Now, there's something I talk about miles in november uh during the cash app launch but like the pace at which you guys have been shipping whether it's that square cash app now big key the new big key proto obviously with the rig it's been astonishing and as an outsider looking in going back to this conference last year actually where miles was on stage talking about the progression of bitcoin within the block ecosystem there seems to be a sense of urgency behind what you guys are building an attempt to to get these tools in the individual's hands so they can actually leverage Bitcoin the right way.

Is that sort of vibe that I'm getting from the outside looking in correct? Absolutely. So there's a phrase that I use a lot internally and lots of us use internally, which is every day matters. And it's one of these things that sounds obvious on its face, like, of course, every day matters. Why wouldn't it? But the difference between teams and people that operate like every day truly matters and any other mode of operation is radically different.

And I think the thing that's really interesting is with that sense of urgency, with acting with urgency is sort of front of mind for us. We're also suddenly like more focused. We have an incredible amount of AI tools at our fingertips that we've been leveraging to move faster, move more correctly, move more robustly. And honestly, the pace has been awesome.

The other thing too, and I think you'll see here at the conference, like we've really started to connect the dots. So in the past, we've talked about our goal being to make Bitcoin everyday money. And we've talked about doing that by making it secure with things like BitKey and Proto. We've talked about making it more accessible

with the Cash App Exchange functionality that we originally introduced now seven to eight years ago. And then making it usable every day with some of the things you've seen from Square and Cash App in activating payments over the past year. And now that we've started to really bring those things together, I think the whole is greater than the sum of the parts

and we're really cooking. Yeah. I mean, you can see like a day in the life of a Square merchant, right? Going about their business, accepting payments, maybe it's fiat to Bitcoin. And then at the end of the day, they want to take some off the platform

and put it into self-custody. could easily integrate with this. And it's it's an urgency that I've again recognized. But I really appreciate it. I do think for the longest time we're at the Bitcoin conference and there's a lot of name particulars. There's a lot of sort of themes that have emerged in recent years where it's focused on Bitcoin as this digital reserve asset this digital gold that never moves. There's no velocity to it. There doesn't need to be. And while I will be the first to defend the properties of Bitcoin as a quasi digital gold and a incredible reserve Treasury asset. That's not enough for me. Like Bitcoin is meant to be peer to peer cash. And I think I feel very fortunate that a company like Block is out there like really keeping that ethos of like no it's going to be everyday money out there because

it is an uphill battle and i would argue it may be more of an uphill battle than it was a decade ago within bitcoin just because this digital gold reserve asset narrative has taken hold yeah and it's uh do you think it will be everyday money i do i do and i think you can see the pieces coming together to make that happen so one of the things i i really like to illustrate this with is actually the square use case so a merchant accepting bitcoin is the type of thing that i think to lots of folks might sound like science project um and you know obviously not at this conference but when you look at sellers broadly like their problems are about operating their business they're about margins if the seller is already a bitcoiner then they're interested

in this but but i think what we see is that people are getting interested in it because of what it can mean for their business so when a seller uses fiat they accept fiat payments there's a three percent fee taken by the networks and on the consumer side you typically see that you know maybe on a receipt you are like upset about the fee that you got charged or maybe you see a sign at a merchant you know tacking on a fee or maybe occasionally on a larger ticket thing you might change, you know, the payment method you use and that sort of thing. And most people on the consumer side, it's an annoying couple of percent. But the thing I like to bring this back to is that for a business that maybe on a great day makes 15 percent margin and maybe on a medium day is a 10

percent margin and maybe has some bad days, three percent, we just talked about 20 to 30 percent of their profits. That three percent is computed on the ticket sales, not their profits. And so it's huge for them. And so, you know, the interest that we're seeing from sellers, some of it's from Bitcoiners, but some is from people that just want to get around the fact that they're getting eaten alive by this sort of thing. And so that's not a block fee. That's not a square fee. Those are network fees. And so we want to enable square seller businesses with that. And I think those types of things like those are that's the beginning of really making Bitcoin everyday money is having those those exact you know benefits to bring people in even if it's not on their radar yet. I mean sticking on the sellers because that's the one thing I've been curious

about since you guys launched it in November. How's that how's that been going in terms of the reaction of sellers that were maybe not even Bitcoin curious but just realize like oh this thing's here. I'm probably not the right person to talk through the whole of that but the one that i'll highlight is that it's incredible how much bitcoiners have come out to support that uh that that activation uh sellers are you get a bunch of influx of people coming around realizing that bitcoin's accepted there the bitcoin map put a lot of sellers in front of local bitcoiners and so on uh and we've seen a lot more people turning it on um and uh and starting to get the benefits

so a lot of momentum and um i think you're gonna see a lot more from us in that area so freaks This rip of TFTC was brought to you by our good friends at BitKey. BitKey makes Bitcoin easy to use and hard to lose. It is a hardware wallet that natively embeds into a two or three multi-sig. You have one key on the hardware wallet, one key on your mobile device and Block stores a key in the cloud for you. This is an incredible hardware device for your friends and family, or maybe yourself who have Bitcoin on exchanges and have for a long time, but haven't taken the step to self-custody because they're worried about the complications of setting up a private public key pair, securing that seed phrase, setting up a pin, setting up a passphrase. Again, BitKey makes it

easy to use, hard to lose. It's the easiest zero to one step, your first step to self-custody. If you have friends and family on the exchanges who haven't moved it off, tell them to pick up a BitKey. Go to bitkey.world. Use the key TFTC20 at checkout for 20% off your order. That's bitkey.world, code TFTC20. All right, freaks. You know me. You know I don't take sponsor money from products I wouldn't use myself. So listen up. The Avon Bitcoin Visa card is one of the most interesting things I've seen in the Bitcoin lending space in a long time. Here's the deal. You can get a line of credit up to a million dollars backed by your Bitcoin without selling a single sat. No gains, no annual fees, no minimum draws, and your Bitcoin is custodied by BitGo,

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slash Bitcoin. That's A-V-E-N.com slash Bitcoin. Check it out. Well, bringing it back to the new BitKey. I mean, you alluded to it, but again, I just went through the onboarding process when we were outside before we hit record. And I think the intuitive nature by which I was telling you is you'll do something on the screen, like put an email in, put a phone number in, put a recovery thing in. You'll do it on the device first. And maybe somebody who knows what's happening i imagine storing that in the secure enclave and then i'm interacting with the mobile app and basically using nfc to move that information from the hardware device to the phone and so it's there and it's in two places at once but between the secure enclaves the

i don't know how to describe it like the peace of mind of like maybe i'm a power user and i understand this but i have a feeling it'll be intuitive for many in fact you have to do it here first, and then you have this active communication between the device and your phone. There's something, I don't know, very wow to me. Like, oh, it is really on here, and I have to transfer it here. Yeah, the core property of requiring hardware

for critical actions, like that signature happens entirely on the device, and you see exactly what's happening, you know exactly what's going on at every moment during the process. I do think that that adds to peace of mind for customers. I think we started off with kind of focusing a lot kind of the onboarding process and the speed of that i think what we found is once we were able

to really optimize those things the next step beyond that is we can give even more peace of mind beyond like the weight and the beauty of the hardware and the ease of the software like by showing people along the way you know exactly what they're confirming um i think people really get a lot out of that yeah and uh speaking of the screen what was the hardest part about incorporate this? Because I know with the old BitKey, you guys designed it and said we're not going to do a screen. It's a little too much work. What convinced you and gave you the confidence to build a screen into this specifically? On the convinced part, our customers. So listening to customers, understanding what they want to see from us and why. As we went through that, we

realized that while maintaining the same great properties of BitKey, we could add this. And I think that's something that as we saw more usage, understood what people loved and wanted changed about BICCI, just fell out naturally in a way that I'm glad we're delivering on. And then on the confidence part, I mean, the team's great and the team's built very complicated hardware across the Square portfolio, but this type of development's never easy. And I think the very direct answer on the hardest part is that coordinating between the phone and and the hardware is not easy a lot of thought went into you know what the phone shows at one time and what the hardware shows at another time and these things are part of a really big recovery system

it's not just a pure signing device biki itself isn't even just a wallet it's a whole system and so we put a lot of thought into how you maintain the state across those two things like you're, you know, signing a particular action here, but, you know, then what do you show on the phone during that time? And how do you make sure that it's intuitive for people? And so you'll even see things like some color matching of what's being, and some animation matching of what's being displayed when it's time to bring the devices together. And lots of details that our designers and firmware engineers and so on spent a lot of time perfecting for you. You mentioned it briefly earlier too, but I think it's important, like, particularly if you're

recycling either wallets or you're changing an email address or contact information on the back end like there's there's a whole process that goes yeah so with with a lot of devices if you're using a hardware device just as a signing device and and maybe that's the the entirety of a product is to provide a signing device and then maybe over here you have systems that folks build that the product is is that system that's you know maybe you integrate other third-party hardware with it and so on. BIC-Key has all of these problems. BIC-Key does both of those things, and therefore we have all of the problems to solve in self-custody.

And as a result, we end up with a system that includes things like a recovery email that we let you know if something is happening with your wallet. And it's actually an account-critical, security-critical action to change that. And so we want you to confirm that on hardware. With the first BIC-Key, you tap. With the second BIC-Key, you actually directly confirm what the email is being changed to. Yeah. No, I mean, especially in today's day and age with all the phishing attacks and $5 wrench attacks that are going on, having to confirm on the hardware is something I'm becoming more confident will be a prerequisite for interacting with wallets in the future.

I guess you need to physically see it here, especially in the world of AI and all this and bringing it back to the atoms of it, which is like you need the thing physically in your hand to change everything. I think it gives me incredible peace of mind. Well, since you mentioned the atoms of it, I'm sort of glossing over all the difficult parts, like developing hardware is never easy and the team spent a lot of time doing doing extensive reliability testing, dropping in from different heights, accelerated aging and those sorts of tests, saltness, things like this. And we want to make sure that whenever we add a component like a display, that doesn't come for free. That comes with very intentional choices about the design and the quality and the implementation.

and really there's a whole journey involved in bringing that into the system and starting to rethink how we can protect even more of the system with this addition. South Freaks, this rip is brought to you by good friends at CrowdHealth. I've been a happy CrowdHealth member for almost five years now. My wife and I have had two children while we've been on CrowdHealth, and I actually just got the last bill for our third child funded. It was $6,157. CrowdHealth negotiated down to $2,309, and we only paid $500.

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it's pink himalayan salt there's no sugar it's way better than lmnt liquid iv i went through a a big electrolyte kick testing them all out and i landed on this settled on this been drinking it pretty consistently every day for two years now it is my favorite this is the pink lemonade they have orange here as you can see this one's ripped i had this on the train ride back from new york last night i'm always stocked up with these things they also have creatine packets very convenient particularly if you're traveling and you like to work out you like if the brain juices flowing they have these creatine packets as well uh they're about to launch a bunch more flavors lemon lime uh watermelon and and a few others as well um so go check it out go to drink

saute d-r-i-n-k-s-o-t-e.com use the code tftc for 15 off seriously game changer in our house my wife drinks it i drink it our boys drink it stay hydrated it's a beautiful thing i mean you mentioned it before we started hitting record but it's been in the headlines a lot this year particularly out of France the the wrench attacks the attacks on Bitcoin holders broadly particularly in that country but outside of that country as well and this is something you guys I don't think you guys are completely solved over this but I think that is a problem that that goes into the thought behind the design of what you guys are building or the one of the bigger problems that you're attempting to alleviate?

Yeah, I think this really comes back to the sort of hardest problems in self-custody list. And this is one of the next ones. So you mentioned BICCI hasn't solved it today. And I wouldn't claim that we have. In fact, I think nobody's solved it. I think it's an industry problem. And I think we see that with both the attacks that we've

seen in France and also lots of the attacks we've started to see in the United States. It feels like there's an acceleration. I think it's pretty clear there is one. And Jameson Lopp's chronicling of all of these, of course, can help put some numbers behind that. And it's something that I think is on lots of Bitcoiners' minds. And I think lots of the solutions that people ideate about today, it's often things like a duress wallet. And it's, you know, things that are make an assumption that during a really horrible, violent attack, that certain things are going to hold true, that in our thinking through this problem space, we question.

We think that, you know, even if you're holding a lot of Bitcoin, most people, there's a lot more important things in life that are if they're suddenly threatened. like it doesn't matter what kind of practicing you did with lying about your balance or you know hoping an attacker hadn't done their research beforehand and so i think this is an unsolved problem and the team has spent some time thinking about and kind of designing a solution that we think is interesting uh it's not something that you know it's not in vicky today um it's actually something that we're kind of at the stage where we'd love community feedback and engagement But basically, our line of thinking is that we need to combine a couple of elements. What we really want is to set up a situation where the Bitcoin just can't actually move right away.

We think that velocity is one of the best possible tools that we can give people, meaning that in some of the attacks and in almost all of the attacks, I think that Jameson is primable, they're less than 24 hours. their attacker showed up and you know they weren't putting themselves at risk trying to hold people hostage for a week or a month and so a lot of our focus is on how can we provide a really safe and easy to use time lock capability that would allow people to set some parameters around how fast their bitcoin can move and find something that works for them for this type of protection and it sounds like the sort of thing that you know you can google time locks if you don't already

know what they are and it's intuitive. And you might think that's an easy solution, but it's far from easy. And so, you know, looking at, you know, in something like the BitKey system, directionally where we're headed is to provide a vault. We'll use that term to describe it here, where basically between BitKey hardware and BitKey servers, your default path is a withdrawal from the vault if you want to move your money and when you do that bikki hardware and bikki servers enforce biometric basically liveness checks uh and um and enforce a delay parameter so like check that you can put your finger on the hardware and maybe authenticate to the bikki app and then show that to the server start a timer and then when that timer expires check those things

again and allow money to move and let people configure what that time delay is maybe set that time delay to a week or a month depending on your parameters maybe longer and then we started going down this rabbit hole and we said okay well it's got to still be self-custody so part of what the time lock serves is that after a certain point it unlocks that policy of biometric check delay biometric check resolves and you can just move your funds in the same way you can today with big key when you have the hardware and phone in your hand then we said okay well there's still a problem there what if the attacker runs off with your keys and they just wait for that time lock to expire so they show up at your house they take your your key and your phone or your hardware

wallet and your phone uh and they leave um and uh and that's that's where he started to realize that okay actually um you know we can do even better than that with what we call an ejection destination so after the time lock send it to a different wallet and this is where it gets really tricky and where we want community feedback this is the type of thing that could be a friend's self-custody wallet it could be another setup it could be custodial wallet and the idea is that you should never be using these this only gets used in the situation where you actually got attacked and they actually left with your keys for a really long time beyond that time lock the default is that instead actually you withdraw from the vault before that time lock expires and

the app helps you do that so not solved yet but that's kind of the design thinking and we're going to share a little bit more about that and we'd love to hear thoughts and feedback and also frankly feedback about whether or not we should build it because we're trying to develop our roadmap in public uh and this sort of thing we'd love to hear thoughts on i mean off the bat i'm hearing this for the first time we've been just hearing this for the first time um yeah i think it's a really creative uh solution right because particularly the time delay like because that's the biggest thing it's like okay somebody comes to your house move it now move it now okay i care about my life okay i'm gonna initiate the move now you have to wait a month okay good luck yeah get out of

of my house. No, it's a shame that we have to worry about this. I agree. And it's one of the hardest things to design around. Yeah, well, and actually on that topic, one thing we realized while we were looking at this is that Big Key might be uniquely suited to design for it. And the reason for that is actually one that I think is a little bit controversial, which is that Big Key doesn't use seed phrases. And the reason it's uniquely suited to Rent-A-Tax is because in that setting, seed phrases are a vulnerability. They're too, they're too instant. They're too portable, like somebody can take and leave with this, and it's very hard to protect it.

And really, you know, what we want to rely on here is Bitcoin transactions for moving money between wallets. And that's, that's kind of the core primitive and the recovery system around BICKEY that makes it safe to not use a seed phrase, kind of sets up BICKEY to be in a position to solve this. So that's part of why we want feedback is, you know, if this is the kind of thing that we can help solve for the industry in a unique way, we'd love to be able to do that. I'm going to hold your feet to the fire and talk about potential

protocol upgrades that could enable something like OpVault or a Covenants proposal, make this easier for you guys or personally as an engineer, like something. Potentially, potentially. I mean, I think the thing that's interesting is it's not required for us and and that's largely because when you have something like the big key server involved you can rely on it for policy enforcement it doesn't need to be enforced by the protocol right so you can basically lean on and you know we could talk about the trust assumptions in this but you can lean on the key servers to enforce that time delay and you know the the underlying

protocol usage can use existing time lock mechanisms without further upgrades to implement something like I was describing now are there proposals that could potentially make allow for different properties of reg tech solutions yeah absolutely but then you get into lots of other trade-offs that probably be a whole nother episode well I think chain code delegations a great example of weighing or designing something to increase privacy in a way that that is enabled by the protocol in combination with your servers at the square yeah uh afshin uh our doubt just launched sigbash which is this similar blinded server sliding uh blinded signing

server which i think that's one thing i'm passionate about is exploring the design landscape of bitcoin as it exists today uh even if it involves bringing in some trade-offs because in a lot of cases the trade-offs are worthwhile it's something i personally can stomach i won't speak for everybody but i look at chain code delegation or something like sig bash like yeah these trade-offs actually make sense to me yeah and honestly that's that's kind of how bicky started right there there uh was privacy trade-off when we first introduced it you know using the 203 multi-sig that we began with has a privacy trade-off. We on the back end have a descriptor for the wallet that would allow big block servers to know about your balance, for example. And with

chain code delegation, we wanted to take a huge step really for BigKey, but also for the industry in terms of that type of trade-off. We wanted it to be possible to get the benefits of leaning on somebody to hold a third key for you, all the recovery and safety benefits while not having the same privacy downsides. And so chain code delegation uses some relatively deep cryptographic magic that I won't go into extreme detail here so I don't bore everybody, basically to make it so that big key servers aren't sitting there with that output or with that descriptor of the wallet, knowing the balance, knowing the history.

And I'm excited that the team formulated that into a BIP proposal, BIP89, and also look forward to feedback on that. So we were talking about it in Georgia at the Proto event. We were teasing it. And, again, going back to the pace of shipping, I think it was less than a month later you guys had it live and then tomorrow. So that was cool to see. All right. Before we wrap up here, what is your biggest hope for this new BitKey launch? What reaction are you hoping BIC winners have when they see this at the market?

I'd love to bring more people into BICU who haven't taken the plunge yet. So we had a lot of people come by the booth when we were selling in person last year. We're doing the same at the conference here. So if you're around in Vegas, I hope that we get to see you. But I think bringing even more folks onto BICU and getting the safety benefits, getting the security benefits, getting the privacy benefits. and finally having something that's really easy to use that gives you all three of those. Okay.

Well, Max, I know you're a very busy man. You guys are setting up. You're getting ready for a big week here at the conference. So thank you for taking some time to sit down with me. And honestly, congrats and thank you. This is a beautiful piece of hardware. And I think a lot of Bitcoiners are going to love this product and share it. That's the one thing you were saying earlier.

People love buying BitKeys to share. with people we've been doing big key giveaways for i think over a year now tftc and that is the number one use case the winner uses it for they say hey i've got one already i'm going to give it to my my dad or uncle who hasn't moved it off the exchange yet so i love it it's a great gift easy to use hard to lose and now even easier to use more intuitive with the screen so congrats thank you thank you max thanks for having me on peace and love freaks all right so we just finished recording before we came in here max set me up with my new big key we funded it with 50 000 sats worth of bitcoin 39.18 sats are cheap right now we're gonna complete the circle it's confirmed

on chain so we can send from this wallet it's gonna send back to another wallet that i control the glare of the light in here I'm going to send $36. I'm going to send 45,000 sats back. I'm going to continue. Slow. Loading the transaction on the phone. I'm going to review on BICKEY. Hold it here. Address, AC1QBBB. All right, looks good. I'm going to confirm here. The address is good. I'm going to confirm the amount.

That looks right. Signing on the device. Initiating transaction. Boom. Done. Same. All right. That worked well.

Congratulations. Thank you. Thank you. First transaction on the newest wiki. Is it? Love that. Well, for you. For me, yeah.

Hell yeah. Congrats, man. This is awesome. Thanks. Thank you for listening to this episode of TFTC. If you've made it this far, I imagine you got some value out of the episode. If so, please share it far and wide with your friends and family. We're looking to get the word out there.

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