There were a total of only 10 grin transactions. Currently grin is not accepted because it broke a while ago and I never got around to fixing it.

I personally bought all of the grin received at the market price when it was received: 80.128295191 grin for 0.0118213 BTC. Not my most successful trade...

Are you guys EXCITED????

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I don't know how it works with mining specifically, but in general: grin payments require a three-way process. This can be done automatically through an IP address or keybase, or you can do it manually like this:

1. The sender runs grin wallet send -m file -d FILE.txt GRIN_AMOUNT, which creates the file FILE.txt.
2. The sender gives FILE.txt to the recipient.
3. The recipient runs grin wallet receive -i FILE.txt, which creates another file FILE.txt.response.
4. The recipient gives FILE.txt.response to the sender.
5. The sender runs grin wallet finalize -i FILE.txt.response, and the transaction is done.

The IP/keybase methods do these same steps, just automatically.

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I'm not going to be mining, but I would like to buy some grin ASAP on the first day. If anyone here is lucky enough to quickly mine some, I'll pay $13/grin (in BTC), but only for the first few grin I buy. PM me.

It's amusing that grin is going to out-cash BCH, using real science instead of dumb parameter fiddling. grin can scale costlessly, and it's also reasonably private like physical cash.

In the far future, I see either a BTC-only ecosystem using various off-chain systems to scale (maybe a grin sidechain), or BTC as digital gold and grin as cash. But there's really no place for BCH's strictly inferior tech.

Since grin started being accepted, 5 out of 687 payments (0.7%) were via grin.


Right, I basically did it just for fun. I didn't expect all that many payments.

I'm super excited about grin. All past altcoins have been just Bitcoin with a few bits tacked on; occasionally these extra bits are useful/interesting (eg. Monero or Ethereum), but in the vast majority of cases this extra stuff is just meaningless marketing-oriented garbage. But grin is packed full of useful innovation from top to bottom; moreover, it's clearly built in the same cypherpunk spirit that Bitcoin was: increased freedom/sovereignty through technology.

Therefore, I'm happy to announce that the forum is now accepting grin payments automatically, probably the first site other than exchanges to do so. You'll find a link at the bottom of the evil-fee and copper-membership pages.

grin is new and clunky to use. I don't expect many people to use it, honestly. But I needed to rewrite the forum payments system anyway in order to support LN in the future and to fix some longstanding issues with the old code, so adding grin support worked out nicely.

I don't recommend buying or not buying grin. Due to its emission schedule, I'd guess that its price will have a general downward trend for quite some time, but who knows. Currently I own zero grin (though I will be buying from the forum all grin obtained), I was not paid to add grin support, and in fact not a soul knew that I was going to do so. grin support might be removed later if it dies off or becomes too time-consuming for me to maintain.

I tested this with grin's floonet (testnet), but not mainnet yet since I don't have any grin. Hopefully it works.

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A few observations I had while implementing this:

By default they want you to essentially pay to IP addresses. This was stupid when Satoshi tried it 10 years ago, and it's stupid now. At the very least you should strongly encourage (ie. nearly force) people to give out public keys along with their IPs, since otherwise MITM attacks are trivial. Even then it sucks to require the recipient to run an open-to-the-Internet server at all. And for goodness' sake, don't use the broken/centralized HTTPS system; the Bitcoin Core devs have been going to a lot of trouble trying to remove that garbage from Core.

A better protocol for the copy/paste method is needed. For one, you shouldn't have to use intermediary files. I was annoyed when I did grin wallet send -m file -d - and it actually created a file called "-" instead of writing to stdout like it should.

grin needs to be much better at handling transactions that never continue beyond the first or second step in the three-way transaction process. They probably shouldn't even show up in the main transaction log.

Currently I think that there's no way for the recipient to get the modified slate after running receive the first time (eg. if it gets lost), which is nuts. And currently there appears to be no reasonable method for proving that you sent a transaction.

The prices and ratios in the forum's automatic payment handling are not permanent, but I only update them manually from time to time.

I've been extremely interested in Mimblewimble since it was first presented a couple of years ago, though I only recently heard that grin is finally launching its mainnet soon. This is the first altcoin that has ever significantly interested me.

I will definitely be buying grin fairly early on. Probably won't bother figuring out mining, though. Note that due to the way grin emits its coins, prices are likely to start out high and steadily drop for the first few weeks/months.

If you're mining grin and want to sell for BTC: let me know and I'll buy from you.

No.


s/fixed supply/predictable supply/

Yes, that combined with its privacy is what makes it so exciting. You can probably achieve even greater scaling with BTC+LN, and I consider that quite likely to be what the economy actually goes toward, but grin is a very different and interesting alternative approach.

I'm not a huge fan of the fixed subsidy, but it is deflationary long-term. Because the subsidy remains the same while the money supply grows (and may shrink due to lost coins), a graph of the inflation rate over time is steadily downward, and will eventually reach low levels. However, since their stated reason for doing this was to ensure that miners are properly incentivized, it would've made more sense to set the subsidy such that the monetary inflation rate is a constant 0.5% or something. As they've designed it, the inflation rate will start out way too high, and then if grin survives for a very long time, it'll eventually become too low to actually meet their goal of incentivizing miners.

Inflation will ensure a general downward price trend for at least the first year, I'd expect, and it becomes sort-of reasonable only after 4 years. Will grin survive that long? Not sure. If you think it will, then it might make sense to buy grin at very cheap prices in its first few years, and this thinking could perhaps stabilize the market somewhat.

Grin inflation rates

Year #	Yearly monetary inflation rate
1	36500%
2	100%
3	50%
4	33%
5	25%
6	20%
7	17%
8	14%
11	10%
21	5%
34	3%

It's possible that people will get just too fed up with the inflation in the first few years, and everyone will move to a clone, similar to the Bytecoin->Monero switch. Beam is too much of an obvious cheap money-grab to succeed IMO, though.

In addition to the money supply issue, grin is a worse store of value than Bitcoin because:
 - The dev culture is built upon a more flexible idea of system consensus. There are expected to be regular hardforks.
 - The crypto is experimental, and the currency is far newer.
 - Smart contracts are more limited, though at this time I'm not exactly sure how much more limited.

A BTC-backed grin clone could be a Bitcoin sidechain, but you won't see this anytime soon. First of all, there sadly hasn't been that much work on Bitcoin sidechains. Also, although you can do a semi-centralized sidechain without any consensus work or widespread costs, a full-security sidechain involves a softfork which would require all Bitcoin full nodes to also be grin-sidechain full nodes, increasing full node costs. I'd guess that if it happens at all, it won't be for 3-5 years, after grin has proven itself. At that point grin could have a significant first-to-market advantage, and its inflation will be reaching reasonable levels.

Unlike the vast majority of other altcoins, grin was basically built in the same spirit as Bitcoin - the same ideology. I'm a "Bitcoin maximalist" because I believe in "the Bitcoin idea/ideology", not as part of some game theoretic strategy to make BTC's price go up. If Bitcoin is out-competed in all respects (which grin is very far from doing, and other altcoins aren't even in contention for), then it'd be good for Bitcoin to be replaced by that competitor.

IMO in 10 years:
 - 30% chance grin is defunct, but roughly the same basic features are provided by other BTC-based off-chain systems such as LN.
 - 25% chance grin is defunct, but basically the same thing exists as a widely-used Bitcoin sidechain.
 - 15% chance BTC is the main store of value in crypto, while grin or a very similar altcoin is used for most daily payments.
 - 1% chance grin advances significantly, and combined with its first-to-market advantage vis-á-vis its innovations, it out-competes BTC entirely.
 - 14% chance some other altcoin out-competes BTC entirely. It won't be one of the existing ones, except perhaps grin as mentioned above.
 - 15% chance global authoritarianism makes it very difficult to use cryptocurrencies at all, and the whole sector is reduced to a tiny niche.

Yes. Grin transactions always work in a multi-step process like this:

There are also methods involving IP addresses, keybase.io, and a "grinbox address" service, but behind-the-scenes these methods do the same steps as above, where the sender and recipient need to cooperate in order to form the final transaction

AFAIK, that medium post is nothing new.

Base mimblewimble isn't really designed to be a "black box of reliable anonymity" in the way that Monero or Wasabi-CoinJoins are, where connections are hard-broken. It's more of a framework on which you could build solid anonymity using techniques that have largely not yet been perfected, plus major scaling benefits. Monero = CT + stealth addresses + ring signatures. Grin = CT + "stealth addresses" + mimblewimble. Because grin replaces ring signatures with mimblewimble, its privacy is less reliable than Monero's. Probably the grin developers have tried to make their mimblewimble transaction aggregation methods good, but I currently wouldn't put much faith in it, and IMO it'll take many years of research to get something really solid. That said, CT + stealth addresses offer a certain base level of privacy, and grin's method of handling stealth addresses (using an interactive protocol, exchanging "slates") is both more scalable than Monero and probably more private.

If your goal is to mix coins, grin is definitely not for you right now, and it may never be. Monero's goal is maximal privacy, regardless of the cost. Grin's goal is excellent privacy, consistent with scaling.

It should be possible if you publish the tx data, but currently there seems to be no functionality for this. This was one of my complaints in my forum-grin-payments thread.

For now:
 - If someone might lie about receiving grin from you, don't trade with them.
 - If you receive a transaction, consider it as absolutely unreliable until it's confirmed.
 - If you send a transaction but the process is interrupted before you finalize it, you need to do grin wallet cancel -t TXID and then (due to a bug which will probably eventually be fixed) grin wallet check

I think that grin-tech.org is just down right now. Nevermind, fixed. Thanks.


Since everyone who invested in howeycoins became a billionaire, I was worried about what would happen to the world economy if I promoted it even more.

It's 14 tps.

It's scalable because it doesn't have ever-mounting costs. If you took Bitcoin and gave it 100 MB blocks, that'd be up to 5.2 TB of data added per year to the history that some subset of users would have to completely store and all full nodes would have to completely download. Altcoins get away with using large max block sizes and saying that they're "scalable" because their blocks are usually empty, so they don't actually have to face the costs.

Grin has a 15 MB bitcoin-equivalent max block size, and while this increases the bandwidth which nodes require (from an absolute minimum of 53 kbps on Bitcoin to 200 kbps on grin - note however that the network cannot function if most nodes have only this minimum), it largely does not increase the history which nodes must keep track of, since mimblewimble uniquely allows the entire network to forget old data.

Maybe in the future there will be a willingness to increase the minimum required bandwidth on grin substantially as global Internet speeds increase. At first glance 200 kbps seems conservative for grin, and since grin does not aim to be a store of value, it can afford to be somewhat reckless anyway. But as long as your network relies on every network participant taking a look at every transaction (ie. on-chain transactions in all decentralized block chain systems), you have no hope of competing with the throughput of eg. Visa, since you have to support ordinary people with less-than-optimized Internet connections running nodes. Global broadcast just doesn't scale well, which is why we're not all tapped into the same Ethernet network. LN can get Visa-level transaction volumes because it keeps most transactions local to the participants.

Mainnet is released: https://github.com/mimblewimble/grin/releases/tag/v1.0.0


Damn, you're right. Well, I'll still buy a few grin as soon as people can sell them.

Grin transactions are not immune to double-spends. Offline in-person Bitcoin transactions would have the same level of security.

It was just an initial burst, there's only been one more since then. 6 out of 1166 total payments.

Someone just today reported to me that they were unable to send an amount with grin's 9-digit precision. It sounds like whatever wallet they were using only supported 8-digit precision. They haven't yet responded to my question as to which wallet it was. If it's a very popular wallet, maybe this has impacted people's ability to pay via grin.

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I still think grin has value to lose since it's so inflationary. In early 2020, inflation will settle down a bit and apparently a GUI will be released, so that's a good guess at an inflection point. But inflation will still be a huge influence for a long time, so I'm not really expecting it to explosively "moon". For example, I think it'll take years to reach $20 again, assuming it survives long enough to do so.

~1.5 MB max block size, with a block per minute. Transactions are much larger than Bitcoin, though. So about 14 tps right now.

Bitcoin's scaling is limited to a large degree by the need for historical blocks to be widely available. Grin on the other hand can mostly forget its history, so its full nodes only need to store/process live transactions, and grin can safely increase its max block size linearly with worldwide Internet speeds and/or CPU speeds.

Many altcoins just increase their max block size and hope for the best, but if any of these altcoins were actually widely used, this would cause severe centralization at best or total system failures at worst. It's like putting a bigger "max capacity" sign on an airplane. Some altcoins have ways of cutting out old history, but although there are theoretically some not-too-bad ways of doing this, usually altcoins do it in really centralized/stupid ways (eg. checkpoints, or ETH "full nodes" just not bothering to verify anything by default), and even in the best case it results in a loss of functionality and security. grin is the first coin with a reasonable, decentralized, and secure way of dropping historical data.

I read the original mimblewimble paper in 2016 and was very interested. I mentioned it a few times on Reddit and here (eg. here). A while later I heard that someone was working on it in the form of grin, but I then mostly forgot about it. I wasn't actively following it. But luckily in December or thereabouts I stumbled upon some article on coindesk or similar that mentioned its impending release.

Glad it worked!