> coins being too difficult to mine without a lot of hash rate It could be easily solved, if blocks with regular difficulty would replace the min-difficulty ones. Because the current rule forces all miners, with CPUs, GPUs, ASICs, or anything else, to produce a min-difficulty block after 20 minutes. However, there are many different ways to handle that. For example: after 20 minutes, block with any difficulty could be accepted, but could be reorged by stronger miners later. Then, the network would never be stuck.
Or: to discourage mining low-difficulty blocks, the amount of the coinbase could be adjusted, proportionally to the difficulty. You don't have hashpower, to mine a block with 1M difficulty, and receive 50 tBTC? No problem, mine million times easier block, get 5k tBTC for testing, and do your tests. If stronger miner will appear, they will have a chance to reorg you, but the same is true in testnet3 and testnet4. > I wonder if the goal of having a clone of mainnet with worthless coins is even possible. Currently, even signet coins are traded for mainnet BTCs, so probably not. By the way: I wonder, if there are any tests, where testnets like testnet3 or testnet4 are still needed. Because most things can be covered by regtest and signet. And if someone needs to test mining, then coins can be locked to a Proof of Work in many ways, and then, miners could claim them, by solving such puzzle. And it works even on mainnet, all you need is using OP_SIZE on a DER signature, to reach an arbitrary difficulty: https://github.com/adambor/btc-pow-locked-outputs/ So, are there any use cases, where testnet5 is needed, and signet cannot be used? wt., 2 cze 2026 o 17:05 Saint Wenhao <[email protected]> napisał(a): > > I am sharing a BIP draft for a new Testnet5. > > Interesting. Does it mean, that testnet4 fixes won't be done? > https://batmanbytes.github.io/testnet4-softfork/ > > > For the Pubkey field, use a recent Bitcoin mainnet block hash. > > Do you mean taking the hash of the block, and using it as x-value for a > public key? Then, it could be potentially spendable, if it would be a valid > secp256k1 point, and people would send more coins to it, or unspendable, if > it would be outside of the curve. For example: > > spendable: > 0200000000000000000001799c6f72ebe5ebc6b18fd5cdf8bd3697b8d73d01b084 > OP_CHECKSIG > unspendable: > 02000000000000000000013ac2955a2b6029bc1a86ab4b19e01e8030ceb0eeb2ae > OP_CHECKSIG > unspendable: > 00000000000000000001799c6f72ebe5ebc6b18fd5cdf8bd3697b8d73d01b084 OP_CHECKSIG > > Also, if the size of the stack push would be different than 33 or 65 > bytes, then it would be unspendable (for example if it would take 32 bytes, > like block hashes, and would be followed by OP_CHECKSIG, to invalidate it, > or if it would start with OP_RETURN). > > > Difficulty: 0x1d00ffff > > I wonder, how quickly it would be listed on exchanges, and traded. Because > historically, new testnets were launched, when that happened. But today, > new coins are listed faster, than they are replaced. Which would give the > creator with any ASIC an incentive, to mine initial 30k or so blocks, keep > them for a while, and then sell for BTCs, when the coin will be listed. > > Also, I wonder if testnet5 will have any premine. Previous attempt to > create testnet5: https://bitcointalk.org/index.php?topic=5543921 > > > Testnet 5 also does not apply the difficulty exception rule from Testnet > 3 or Testnet 4 requires. > > It would be nice to simplify the code, and remove that rule completely > from sources, but it would probably take a while to deprecate testnet3 and > testnet4. > > wt., 2 cze 2026 o 13:27 'Pol Espinasa' via Bitcoin Development Mailing > List <[email protected]> napisał(a): > >> Dear list, >> >> I am sharing a BIP draft for a new Testnet5. >> People are complaining about Testnet4 being difficult to use, the new >> testnet also works as a miner playground for BIP54, we are killing two >> birds with one stone. >> >> You can find the full text to read and comment on in the following draft >> PR: https://github.com/fjahr/bips/pull/2 >> Feel free to leave inline comments there or respond here on the list. >> >> >> Pol >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Bitcoin Development Mailing List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion visit >> https://groups.google.com/d/msgid/bitcoindev/BrgqDZiNhpEz32-Z9ZX2rrPDE9EUIb62SKT2WsTo-yZtd3gLMLVk6TkO6kLIR96-87TumXqi92l_m1j3xlJr1tcJwG_I3UVDk2NZgXZL8fw%3D%40protonmail.com >> <https://groups.google.com/d/msgid/bitcoindev/BrgqDZiNhpEz32-Z9ZX2rrPDE9EUIb62SKT2WsTo-yZtd3gLMLVk6TkO6kLIR96-87TumXqi92l_m1j3xlJr1tcJwG_I3UVDk2NZgXZL8fw%3D%40protonmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "Bitcoin Development Mailing List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion visit > https://groups.google.com/d/msgid/bitcoindev/CACgYNOKGG1ht-2deT3jP81BzMrcqYd8tTL-tXeX-Z5sugUngJw%40mail.gmail.com > <https://groups.google.com/d/msgid/bitcoindev/CACgYNOKGG1ht-2deT3jP81BzMrcqYd8tTL-tXeX-Z5sugUngJw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Bitcoin Development Mailing List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/bitcoindev/CAN7kyNiH_8hnBmxBR8rPc%2BwYwbKPRy51yif3jRXofHbFFKsSgQ%40mail.gmail.com.
