This thread collects frequently asked questions and their answers. If you have a question you would like to add (and prompt an answer for) feel free to ask it below. Note that not all answers were written by the thread owner.
How does mining work? What resources are required?
In Neptune, mining consists of two steps: composing and guessing. The composer assembles a block by aggregating transactions and producing a proof of correctness of the entire batch. The guesser supplies the nonce such that the block’s hash is smaller than the target.
Proving is expensive and if you want to do it fast you need a lot of RAM. Think 50+ cores and 150+ GB of RAM. Also: up to a limit, composing is faster when you throw more cores at it. To enable composing, start neptune-core with the flag --compose.
In contrast, guessing can be done on any machine that’s capable of synchronizing to the network. By default, it will use all the available cores. Guessing is stateless, meaning that it doesn’t make any sense to buy half the number of computers (or cores) that work at twice the speed. What matters is the total number of hash trials per second. To enable guessing, run neptune-core with the --guess flag.
The producer of a new block is entitled to any transaction fees of transactions confirmed in it as well as the block subsidy. The composer allocates to himself a proportion of this reward at his discretion; the remainder goes to the guesser. By default, composers are configured to broadcast their proposals but people who aren’t afraid of digging into the source code might change this configuration.
One last point: all mining rewards are split into two parts. Half is liquid immediately. The other half is time-locked for three years. This dynamic aligns miners’ incentives with the long-term success of the project.
What is the current circulating, liquid supply?
In the first three years, 64 liquid coins come into circulation with every block. So multiply 64 with the current block height (7968 at the time of writing) to get the circulating supply (in the running example, 7968 x 64 = 509 952).
Where can I check the block height / other blockchain data?
On our block explorer which we run an instance of on neptunefundamentals.org/ and on explorer.neptune.cash.
Feel free to run your own block explorer by running this software on the same machine that runs a neptune-core node: GitHub - Neptune-Crypto/neptune-explorer: Block explorer for the Neptune blockchain
There’s also a third party block explorer: neptune.vxb.ai.
What’s the distribution of mined coins? And is there a list of who the biggest holders are?
This is a privacy-preserving blockchain. That data is not available. No amounts are publicly visible, and you cannot in general see if a specific UTXO has been spent or not.
What’s the emission rate?
A new block comes in roughly on average every 588 seconds, which is almost ten minutes. That’s 144 blocks per day. Multiplying 128 with 144 gives a new supply of 18’432 coins per day, of which half is immediately liquid. The rest of the mining reward is time locked for three years. So the emission rate of liquid coins is 9’216 per day.
Can I run a test network?
Yes! just launch the client with the --network testnet argument to run the client on a global test network (whose history is preserved indefinitely). And launch the client with the --network regtest argument to run on a test net whose state is reset every week and is intended for local testing.
Notice, though, that I’m not aware of any clients running on the global test net (--network testnet). So don’t be alarmed if you’re not finding anyone to connect to.
How big is the premine, and when it is released?
The premine is 831’488 coins, which is a a little less than 1.98 % of the final, total supply. The final, total supply is 42’000’000. The premine is locked for six months from launch. So it’ll be fully liquid around August 11, 2025.
Note that there is some disagreement about the definition of a premine. The premine I’m referring to here is a distribution of coins that was baked into the genesis block. The genesis block contains 80 outputs of a total value of 831’488 coins. These outputs are timelocked for six months as mentioned above. All other coins (98.02 % of the total supply) are mined competitively.
What’s the difference between {block subsidy, miner reward, composer fee, guesser fee, coinbase}?
- block subsidy: newly minted coins. Right now every block is allowed to inflate the money supply by 64 coins that are immediately liquid and 64 coins that are timelocked for 3 years. Roughly 3 years after launch, those numbers will halve.
- miner reward: block subsidy plus transaction fees, originating from transactions confirmed in that block. Note that you can’t necessarily tell how much the total transaction fee is because the composer can gobble them.
- composer fee: the part of the miner reward that the composer gobbles up. This fee is a transaction output like any other, with no distinguishing features — and in particular, the amount, origin, and (if it is ever spent) destination is hidden.
- guesser fee: the part of the miner reward that is not claimed by the composer. It is left in the block transaction, and automatically goes to the guesser who finds the right nonce.
- coinbase: a term borrowed from Bitcoin, where it denotes the first transaction in a block (i.e., the one that is allowed to not have an input and thus inflate the money supply). We use this term rather improperly to denote a transaction that has no inputs but does have outputs, and that’s okay because there is a block subsidy to spend. It is typically the first transaction in a chain of mergers that eventually leads to a block transaction.