I want to set up a shared Bitcoin wallet where everyone can see the wallet from their individual phones. This will be the only wallet on their phones.

No singular individual should be able to spend funds from that wallet without another individual. Probably something like 2 of 4 multisig.

The problem is it appears that multisig actually works more like a "vault" where the keys from other wallets sign transactions from that wallet, which means each family member would need their "key" wallet and the family wallet if I am not mistaken.

Can someone give me some guidance? I was also thinking about using Blue wallet because it is very simple for setting up multisig and is cross platform for Android and IOS which is a must have.

I am looking for not exactly a cold "vault" storage, but more like a luke warm family fund that everyone can collective contribute to and manage in a democratic fashion for all the unexpected things life throws our way. Once I figure this out, I will then begin to slowly peel off my accumulated Bitcoin by contributing a monthly amount to the family funds.

related
  1. A "vault" wallet should not be "shared". Yes, you could create an "intermediary" cache wallet where everybody could have access, but not with all your funds. Your HODL savings should not be shared, not even in multisig or with family.
  2. If you really want your family to see that "vault" wallet you better give them access only with a "watch-only" solution (many mobile wallet apps support to import a xpub) and they can have direct access to check balance and also generate new addresses to make new deposits. NOT moving funds from it!
  3. Use the "three levels stash" method for all your BTC wallets.

3level-stash.jpg

  1. Each member is better to have its own vault, cache and spending wallets.

Never trust human stupidity / ignorance / lack of knowledge. Shit can happen all the time, even with advanced users.

I did not say that I was going to dump my entire savings into this. I do not want a watch only solution, none of this addresses what I am trying to accomplish.

Have you tried https://nunchuk.io/ ?

I have started using it to manage small collaborative projects with trusted people. For example, when you want to start a blog, need to buy a domain name, and some hosting, receive some support funds, etc... And want to share the responsibility.

Nunchuk allows the creation of a discussion space with as many participants as required by the "project", then attach a multi-sig wallet to it. You can discuss buying something and the transaction will be posted inline the conversation, executed by the multisig rules of the wallet.

I am going to report on the experience in a bit more detail after we have completed our first collaborative project using Nunchuk, stay tuned ;)

I would upvote that post. Would be great to read.

Excellent. I recall hearing some things about this and will look into it more. Between this, blue wallet, and fedimint I belive I can cobble together a working solution worst case scenario.

I will try to keep an eye out for your report!

1 sats \ 1 replies \ @pi 21 Jan

Is nunchuk still beta?

0 sats \ 0 replies \ @pi 21 Jan

Apparently not anymore and they look like a good alternative to casa! https://nunchuk.io/pricing

We have 2-of-2 multisig setup with Blue Wallet with me and my wife, works well. We can receive funds individually to it, for sending out need to confirm from both devices.

That is cool, could you explain the setup a little more? Do both phones have only the multi sig wallet? So both can send funds to it any time, but you both have to agree to spend any funds from it?

Yes. Well, tehnically we might have more wallets with Blue, but that's not related, you can just have unlimited amounts of onchain and lightning on Blue Wallet.

Yeah I love how clean Blue is. Aside from that setup, I also have my own Lightning wallet using Blue. Couldn't have been more simple. I am not annoyed with promotions and incentive deals and all this bloaty crap you find even in other Bitcoin only wallets.

30 sats \ 1 replies \ @duvel 21 Jan

Fedimint could eventually be a very good fit: https://fedimint.org/blog

Ah this is the project I was trying to remember but could not recall the name or describe it correctly. I will deep dive this and keep a close eye on it. Thanks!

10 sats \ 1 replies \ @ama 20 Jan

I'm not 100% sure that will work exactly as you want, but it might be a first approximation to try out, maybe. You could install the same wallet, with the same seeds (use the same 12/24 words) in all four wallets, and make it a multisign wallet so that each member of the family has a hardware signer of which two (of the four) are needed to sign transactions.

Yeah I am not totally sure what I want is possible. I wonder if its just a matter of wallet UX or if there are any technical limitations as well. This is probably where all those managed services like Casa come into play.

Another structure I thought would be interesting would be one where each individual has an "account" that exists within the main wallet. The idea being that they can send and move funds out of their "account", but no access to anyone else's funds. However, the wallet would show the sum of all accounts and if enough "accounts" agree then funds can be spent out of the main wallet directly.

What a brilliant way to have smaller amount of funds available for the family. While it restricts any one person from spending, it does allow any 2 people to spend. Kind of a checks and balance so no one person can spend it all without at least one other person of the group knowing about it. Normally a multisig requires the first spender to send the transaction to a second spender in order for it to be fully approved before broadcasting the transaction. Just thinking about how to test this without putting too many sats at risk. Perhaps setup a 2 of 4 wallet in Bluewallet. Then have 2 phones with the wallet setup, each with a different approval key. Then try to send a small amount to a different wallet as follows: Phone 1 creates a transaction. Phone 1 sends the transaction to phone 2. Phone 2 approves the transaction. Phone 2 broadcasts the transaction to the network. Payment done.

Happy Bitcoining :)

I am not completely familiar with multisig, but if its something that you can only do on the Bitcoin base layer, then you don't have to worry about testing lighting. If Blue wallet lets you set the node to connect to, you could just run a Bitcoin testnet node locally and do your tests with as many sats as you need.

Don't even need to run test net. Can just run Bitcoin node locally by creating a genesis block too.

We use Electrum mobile wallet basically as a shared business wallet for my partner and I.

We set it up as a 1 of 2 multisig so either of us can spend the funds without bothering the other.

As far as I know, Electrum is "m of n" flexible, so you can set up a 2 of 5 multisig, for example.

It was pretty straightforward and we've been using it for a number of years now.

What is the purpose of multisig for you? Why not share just the one key? Having two keys seems like you just double your attack vector in this scenario.

Self-sovereignty means the individual, democracy is mob-rule and not the basis of western civilization. Plato's republic and Federalist papers #10

Spare me, I know all this. I have been exposed to Bitcoin for its entire life time. There is a specific reason I am choosing to handle things the way I am.

You posted this on a public forum and I had the democracy argument in mind so I posted. Not insinuating ignorance. Also interested in this initiative with onboarding/adoption in mind- seems strange to me that your family vault wallet will be "the only wallet" on your family's devices. Why not encourage them to take custody over other (smaller balance) wallets as well?

Yeah my bad about that. Have some Sats for your trouble. The reason is even though that is the correct path, my family members are 1 password using (and sharing) type people. There just isn't a reality where they care enough to do this responsibly or reliably.

Even worse than this just being isolated to my family, this is not at all uncommon. It is the majority of people. I hope for change on that some day, but we do not live in a society that even allows for the thinking skills needed for that to happen in the first place.

The end goal being no one person with the main wallet phrase can take or spend anyone else's funds.

I have a good chunk of this worked out in my head if I were to develop my own wallet software but I wouldn't know the first thing or be able to do any of the math to do that.

I think though it is a matter of wallet UX. A Bitcoin seed phrase can have an additional passphrase called a two factor phrase. This can be anything you set it to.

The way I understand it is that the additional passphrase means you have a completely independent wallet because the hash or whatever that seed phrase + passphrase represents is different from just the seed phrase.

So that means you can have crazy scenarios like this:

Main wallet | |-sub wallet1 | | -sub wallet2 | | -sub wallet(2of3)

So you can have multiple "sub wallets" and have "sub wallets" that are also multisig. I don't know if the main wallet can be multisig or not and what the implications of that would be.

But each of those so-called sub wallets can have their own balance entirely unknown and undependable by anyone else who also has the passphrase of the main wallet. While this is typically used as an additional layer of personal security I think with enough ingenuity it could be used in some way to facilitate my goal.

The problem is there isn't really a reliable way to have some sort of global family balance. I guess to be even more clear what I am looking for isn't a savings solution for my family exactly. It is more of a family managed pool of money where participating members can collaborate in a democratic way about how the collective funds are spent.

Someone mentioned nunchuck so I am looking into that. I am really just trying to find ways to lessen the burden of self custody while still maintaining good enough security. Not an easy task but there are few collaborative solutions in Bitcoin. Inheritance solutions are worse.

I don't think this will be something I go through with because the more thought I put into it the harder it seems to pull off. I thought about setting the family up with multi sig stuff but that actually just adds to the complexity of things to track and keep secret as far as I can tell.

One of the reasons I know Bitcoin is the future is the clear difference in online interactions in this community turning out positive when anywhere else they would devolve into insults or just end abruptly =) Let's see if my thinking would help you.

First: here is a presentation I was watching about multi-sig. I think it would make your goal possible but it does have the higher complexity. (or cost- everyone gets their own hardware wallet) Start at 2:48:25 https://youtu.be/40mdFIAEh4E?t=10105

However, like you said, maybe attempting multi-sig for extra security is not the explicit goal here.

How about a single hardware wallet > watch-only wallets (same public key) on each of your family's devices? https://bluewallet.io/watch-only/

-Hardware Wallet located in your possession / family safe / family trust. -BlueWallet app so your family can easily create their own other wallets + generate receiving addresses for the FamilyVault wallet and contribute to it.

This at least achieves the awareness/tracking and contribution for the Vault wallet by each user, but the multi-person approval feature would be offloaded to a physical process of taking possession of the master hardware device.

Yeah it is hard to consider the person on the other end when we all strive to be so invisible.

I will look into this. I was thinking of some sort of way to have the hardware master vault on multi-sig, but each watch only wallet under the same master seed phrase + whatever private password phrase they choose and no multi sig.

If that could happen then I think most of what I want can happen. They could use the hardware wallet to access their vault under their passphrase to spend funds. The main family vault on the hardware wallet could not be spent by the individual but the balance should be viewable and xpubs exportable so all family members can still verify funds in the main vault are good.

The only missing piece of this would be the fact that all funds are separate and members would need to contribute to the main vault rather than the sum of everyone's balance be apart of it.

I definitely have a vision in my head on how to solve that last piece but there is no way I could do it on my own. It will require building a wallet from the ground up.

Ordered some hardware wallets to see if I can at least execute on everything else though.

для начала раздай всем по 24 и попробуй это оргонизовать... далее тебе интуиция подскажет как поступить и твои семейные дадут советы как сделать верно...