Chrono Cryptocurrency App


The Decoin app I described earlier is based on proof of work (PoW). That’s useful for making the coin a scarce resource that has to be mined. There is however a major drawback with PoW which is that users have to burn resources including CPU hours and electricity.

Safecoin has proof of resource instead of PoW, which is excellent since instead of wasting computing resources on mining, such as in Bitcoin, safecoins are earned for delivering data chunks on the SAFE network. That’s great for farming, but devices like smartphones are less suitable for farming safecoins.

To solve those problems mentioned above I here introduce Chrono, a cryptocurrency based on calendar time. Users are able to mint a certain amount of coins [to be determined] per hour and the ID for each coin is:

chronoId = hash(signature(utcTimestamp))

Where utcTimestamp is the number of milliseconds since Jan 1 1970 quantized to the allowed number of coins per hour, and signature() is the signature generated when signing with the user’s private key.

To verify that a coin is valid the signature has to be correct and the timestamp has to be greater than a start date for Chrono [to be determined], match the quantization model and be less than or equal to the current time plus/minus some margin, such as one minute.

It’s up to the receiver to have an accurate clock in his or her computer. If a user has accepted an invalid coin in a transaction then that coin will be refused by others when the user tries to send the coin to someone else.

Double spending and double minting are prevented by there only existing one unique combination per quantized time and signature. And assuming safe digital signatures, it’s impossible to guess what the ID of a coin is beforehand without having the private key.

The minted coins are then used as genesis coins for transactions. One problem to solve is how to efficiently allow divisibility of the coins.

Another big problem that remains to be solved is to prevent people from creating lots user accounts. But if that can be solved then chronos can easily be minted with all kinds of devices, including smartphones.


So why will people use it?

Is this a coin just to have a coin?

You mentioned SAFEcoin and to compare SAFEcoin has a use/purpose and as far as I can see this coin is simply a coin to be a coin.

Oh the safe network has no time so everyone can create coins from the past (after coin start) as long as its less than what everyone else thinks the time is.


It’s easy to mint chronos, yet there is still scarcity since there is a limited number of coins that can be generated per day. So chrono as a cryptocurrency will have some real fiat value I assume.

At the moment Chrono is just a concept but I wanted to post the idea immediately in case someone else will come up with the same or similar idea in the future.


True, but that just means that each user has the same amount of coins available. No first-mover advantage for minting coins. The problem with unique human accounts remains though.


An additional possibility I want to mention, to protect the idea, is to have a “use by” date for the coins. Then the chronos are only valid for a fixed time period. That prevents hoarding and incentivizes high velocity for the currency.

The actual use by date is to be determined but let’s say for example that the chronos become invalid 1 month after minting. And the denomination of a coin can be set proportional to the age of the coin. A coin older than 1 month (in the example) has zero value, and a coin minted with current time timestamp has maximum value.

That’s a very different economic model than traditional cryptocurrencies, and it might not work for practical purposes or it may work. It could be interesting as an experiment at least.


Can you code up this coin?

Not that I’m an expert but this is called demurrage, blablabla
Have a look at Freicoin or Chiemgauer

You can have humans id each other and stake their coins, to id another person as unique human or just use @ seneca’s web of trust and allow tokens to only be send to people in your web of trust (if this is even possible)

I rather see you printing decentralized money and people having the choice to use it or not. Your token has value on my ad platform :stuck_out_tongue_closed_eyes:

I would exchange 100 euro’s for a few of your tokens as an experiment :rofl:


Oh, my additional idea is already used in Freicoin. My core idea is still unique though I think (hope).

And to make it simple I have an idea to make the chronos existing permanently (no demurrage) so that they can be hoarded like most other cryptocurrencies. And also to have the chronos indivisible to make it easy to implement a first version, maybe for the SAFE beta version.

For example with the timestamp quantized to hours, then 8,760 chronos can be minted per year by each user. The minting has to be tracked so I will need multi-signatures (user + app) to prevent other apps from minting coins. Other apps can create Chrono wallets (the Chrono spec is open source), but only for receiving and sending chronos, not for minting.


Hoarding is not the future, demurrage helps to keep a currency circulating, ideally you would want to make the Chronos quickly available for people who need it (to pay bills, for their ICO, so if your app could lend/donate unused tokens it would help).

Becoming the new federal reserve won’t help your project. People don’t use tokens because they are unique or have a pricetag, they use them because they can be used to pay for goods or services. Here is a token with a marketcap of over $400M, but it’s completely worthless, because it can’t be exchange or used for any service.

To give you an example why our advertising token will exists.

  • First it’s to fund the development of our app/SAFE specific hardware and do a whole lot of experimentation to further the growth of the SAFE Network.
  • Second it can be used to advertise on our ad platform, with a 10% discount, the ad platform will enable payment with every SAFE token or other crypto out there.
  • Third it will play a little with time&money, at it’s early stage 1 token represents 1 day of advertising. Through user growth (maybe Seneca’s WOT can help here) a tokens timespan will go from a day, hour, minute to a second. The token will keep it’s timespan that you bought it at, even if the new time segment kicks in.

There is more, but :zipper_mouth_face:

The are other projects that do minting, like the federal reserve, I don’t know if you heard of them? But their luck is that they had a lot of time to spread their currency, so distributing your token will also be super important. The feds do got a trillion $ playground, so maybe worth pursuing…


Yes, demurrage will increase the velocity of the currency I think.

Wikipedia: “The term “velocity of money” (also “The velocity of circulation of money”) refers to how fast money passes from one holder to the next.”

Demurrage is an interesting property, but since the Freicoin already has that I thought I would drop that feature. And also, to make Chrono really easy to implement (e.g. as my first SAFE project) then I have to drop the demurrage idea because it becomes rather messy to implement it seems.


Freicoin is blockchain based, this is a whole different ballgame and worth trying IMHO. Currencies with demurrage have a track record of being successful in the real world (Maybe your app can enable community currencies).

If you got the time go for the messy (Always when people say messy, I think Messi, maybe that’s why it’s a different ballgame :stuck_out_tongue_closed_eyes:) go for messy, because it’ll give you a better understanding I suppose about the SAFE Network coding, get your hands dirty. It would be nice if you made it as an tutorial also, because every SAFE Network developer is a teacher IMHO and there is not enough teachers out there yet. Maybe you can add some feature from Chiemgauer (2% lost after 3 months or 5% when you exchange it), but instead of lost if the 2% went to the other tokenholders after 3months or 5% went to SAFE Network specific projects (especially projects/services that use Chronos) when Chronos is exchanged, I think you might be on to something. Sorry for making a bigger mess of your feature set, but these %s could add up why people would want to have Chronos. Good luck and you have my money if you code it up. Think about the marketcap and funding future SAFE Network projects we’ll need a lot of projects doing that going forward. :stuck_out_tongue:


From an end user perspective demurrage makes it more complicated so I think I will have the chronos be permanent like ordinary cryptocurrencies.

In either case, the main problem is how to ensure unique user SAFE accounts. MaidSafe has shown interest in proof of unique human so maybe they are planning to have something like that at some point.


Sometimes I think if you let someone upload their passport + a video of themselves and this data would be ided by familiy/friends that way you defeat this unique human id issue. But to ID another person must also come with a cost, to prevent misuse, but the next problem is what if they get hacked? I don’t know if it’s wise to add biometrics (+ companies should never have this data of people).

Civic is an ID solution in the cryptospace
, here is it being used in the real world.

I didn’t pay a lot of attention to how they id people and if this data is kept on their servers.

This Civic app would be great to log into the SAFE Network, but if it remains centralized :weary:

I see @bochaco app replacing it


My current plan is to drop the unique account requirement and replace it with proof-of-work (PoW) after all. In practice I think it will be too tricky to assure unique user accounts. The PoW will be easy to calculate so PCs and maybe even smartphones will be able to mine chronos. The coin ID is:

coinId = hash( hash(utcTimestamp) | nonce )

The nonce is a fixed number of bytes and the timestamp is quantized to allow a certain limited amount of coins to be mined each year.

The coinId needs to be less than a fixed target difficulty in order for the coin to be valid, and the timestamp needs to be greater than the Chrono start date and less than the current timestamp +/- a time margin.

If someone premines coins then the receivers of transactions will reject those coins. And the timestamp makes it possible to change the Chrono specification while still making the old coins valid. Anybody can develop Chrono miners and premine coins for future use, but then there is a risk that those coins will be invalid if the Chrono specification has changed by the time the coins reach a valid calendar date. Mining coins with valid timestamps ensures that the coins are accepted and will continue to be accepted in the future.

EDIT: And in order to prevent too much premining the target difficulty can be made to increase over time according to a predefined formula.


Just a couple of questions and if one of the first four is no, you can stop there.

  1. Are you aiming for a basic income cryptocoin?
  2. Do you live in the EU?
  3. Are you okay with the EU?
  4. Are you willing to have the verification process of such basic income cryptocoin be done by your government or an EU government?

  1. Are you okay if I’m going to call the coin European Basic Guilder instead of some bastardization of Krona, assuming you’re Swedish?
  2. Are you okay with teaming up with European Federalists? I plan to ask in those circles, because I think that’s where I’ll get the most support for this.


With proof of unique human for the SAFE accounts, then yes it would be kind of like a basic cryptocurrency income since all accounts can mint the same amount of coins over time, although it will likely be a puny income since the chronos will probably have a low fiat value. I live in Sweden but Chrono is meant as a global cryptocurrency including the minting of coins. So then something like a United Nations human digital ID is needed but that will take many years to implement and there is a risk of too much Orwellian control with such global ID system.

There have been discussions about unique human SAFE accounts on this forum. That’s a better solution in my case without the need for national or international governments.

My latest idea is to skip the unique human account requirement and use proof of work instead. I’m not fully satisfied with any of my solutions yet but I find it interesting to investigate these ideas.


My aim is 2% EU GDP per capita per year.

I didn’t know SAFE was working on this as well. Thank you for the information.

I’m still going for national (although in this case the EU) government.
I have the feeling governments and their citizens want monetary sovereignty whenever they do not agree with other governing bodies.


You could implement another coin similar to Chrono because it’s open source and license free.

With an EU digital ID system for citizens it would work. That’s way over my head though but if you think you can pull it off that will be quite a feat. You will have to talk to and convince top EU politicians!


This already exists. There isn’t a single EU standard though.

In Sweden you have BankId and maybe others.

There is a cost though, something like 1€ per signature.

Most developed countries have a working digital identity system or have one under development. Mygov in Australia, verify in UK etc. I guess they might not all be open for use by the private sector, but many are.


BankId in Sweden is around 500eur setup fee and then each login/signature depends on volume, but you can get lower than 1eur per login.

Banks manage these signups though, and they have rules for the kind of business they allow. I think cryptocurrency area will still be a hard sell. Generally, you’d have to have a quite established business.

I have integrated with BankId and it’s quite straight forward actually.
Instantor is also considered a qualified electronic signature, and will be valid as identification of unique human per Swedish law currently (probably for EU in general).
It is however a much more privacy intruding service (you allow access to bank account statement for all your accounts at the bank you chose to login with), and a more complicated integration.
Easier to setup deal with, works for multiple countries in EU, much more expensive per login (many times more). Gives a lot of data, i.e. much less privacy than BankId. Good/bad depends on where you see it from.


No they aren’t. It was a discussion which still considers it not possible and keep any form of anonymity. All the methods that may prove unique human has exceptions (5+%) and requires central registry. Even DNA sees the problem of some people who have two dna sequences which featured in one court case where they “proved” a mother was not the mother until they took dna from another portion of their body and estimates are that a significant portion of people are like that. Any “proofs” that can keep a form of anonymity can only really attempt to prove human and not unique human.