TwistCoin Whitepaper

1. Abstract

TwistCoin is a cryptocurrency forked from Bitcoin Core v31.1. It keeps Bitcoin's transaction format, script system, SegWit, Taproot and SHA256d proof-of-work unchanged, and changes only what a new chain has to change: its identity (genesis block, network magic, ports, address prefixes) and its pacing (2-minute blocks, faster difficulty retargeting, 20 TWIST initial block reward, halving about every two years).

The project exists for home miners. Anyone who owns a small SHA256d ASIC, such as a Bitaxe, can point it at TwistCoin and find blocks on their own, with the full block reward going to their own address. There was no premine, no founder's reward and no developer fee: the genesis block was mined live by a real home ASIC at the chain's real starting difficulty, and its message commits to a recent Bitcoin block to prove when mining began.

This document describes the design, the monetary policy, the launch, and, just as plainly, the limits and risks of a small proof-of-work network. The changes made to Bitcoin Core are reviewed line by line in the separate code audit.

2. Motivation

Bitcoin mining started as something anyone could do on a home computer. Today, a home ASIC of about 1 TH/s mining Bitcoin alone would expect to find a block once in thousands of years. Solo mining Bitcoin at home has become a lottery ticket, and pooled mining pays home miners amounts too small to matter.

TwistCoin starts over with the same proven software, sized for small hardware. At launch, the difficulty was set so that one 1.3 TH/s home ASIC finds a block about every two minutes. As more miners join, the difficulty rises and each miner's share of the blocks shrinks, exactly as on Bitcoin. Early on, though, a single home device can take part in a real proof-of-work network, verify its own blocks with its own node, and watch them confirm on a public explorer.

The second goal is to do this honestly: a clean, readable fork that anyone can rebuild and check, with the launch and every change to Bitcoin Core documented.

3. Design: Bitcoin, retuned

TwistCoin Core is Bitcoin Core v31.1 with a small, reviewable set of changes. Everything that defines how a transaction is built, signed, relayed and validated is inherited unchanged. All soft forks Bitcoin activated over its history (BIP34, BIP65, BIP66, CSV, SegWit, Taproot) are active from block 0, since a new chain has no old blocks that need exceptions.

Because the block weight limit is unchanged and blocks come five times as often, the chain can carry roughly five times Bitcoin's transaction throughput. Confirmations come faster too, but a TwistCoin confirmation carries far less proof-of-work than a Bitcoin one (see Security model).

TwistCoin uses its own network magic bytes, ports, address prefixes and signed-message prefix (TwistCoin Signed Message:). A TwistCoin node never connects to Bitcoin's network, and a TwistCoin address or signature can never be mistaken for a Bitcoin one. The two chains share no history and no coins, so a transaction from one chain can never be replayed on the other.

4. Monetary policy

New coins enter circulation only through block rewards. The reward starts at 20 TWIST and halves every 525,600 blocks (about two years at two minutes per block). As on Bitcoin, the reward is computed by repeatedly halving a whole number of wisps and dropping any fraction, so it reaches zero at the 31st halving, about 62 years after launch.

Adding up every block reward gives a hard cap of exactly 21,023,999.931672 TWIST. Like Bitcoin's genesis block, the 20 TWIST reward of TwistCoin's genesis block can never be spent, so at most 21,023,979.931672 TWIST will ever circulate. The cap is slightly above 21 million because 20 TWIST × 525,600 blocks × 2 = 21,024,000, whereas Bitcoin's 50 × 210,000 × 2 is exactly 21,000,000.

This is an upper bound, not a promise of how many coins will exist. A miner may claim less than the allowed reward (the difference is lost for good), and coins whose keys are lost still count toward the supply but will never move. Transaction fees create no new coins; they only move existing coins to miners. Once block rewards end, fees alone pay for mining, the same long-term model as Bitcoin.

5. Fair launch and genesis block

A coin is fairly launched when no one could mine it before everyone else was able to, and no coins are set aside for insiders. TwistCoin makes both checkable.

The genesis block commits to a Bitcoin block

Like Satoshi's newspaper headline in Bitcoin's genesis block, TwistCoin's genesis coinbase carries a message that could not have been written before a certain moment:

TwistCoin 15/Aug/2026 - Bitcoin bloc 962555 22e46e8ef4eba72391b65a7409148a585a52e82d42106

It names Bitcoin block 962,555 and its hash (with the leading zeros left out, so that the message fits the 100-byte coinbase limit). That hash did not exist before that Bitcoin block was mined, so no TwistCoin block can be older.

Mined by real hardware, at the real difficulty

Many new chains start from an easy genesis block found on a laptop, then let the difficulty climb for hours or days. That ramp-up gives whoever is mining at the very start a large, cheap head start. TwistCoin skipped it: the starting difficulty was calibrated to a real 1.3 TH/s home ASIC (difficulty = hashrate × 120 s / 2³² ≈ 36,322), and the genesis block itself was found by that ASIC through a small custom Stratum server. Finding it in software at this difficulty would have taken more than a year of CPU time. From block 0, the chain ran at the difficulty it was meant to have.

No premine, no founder's reward, no fee

The genesis reward can never be spent. No later block pays anyone except the miner who found it: there is no developer fee in the consensus rules, and the public pool takes no fee either. Like any fair launch, the first blocks went to whoever was mining at the time, which at first was the project's own home ASIC. Every block and every coinbase payout since then is public on the explorer.

6. Mining

Any Bitcoin-compatible SHA256d ASIC can mine TwistCoin without firmware changes. Point its Stratum settings at a TwistCoin pool, with a TwistCoin address as the username (see Mine).

The public pool, pool.twistcoin.org, is a solo pool, forked from the open-source Public Pool project. It does not share rewards between miners. Each miner works on block templates that pay the whole reward to their own address. If their device finds a block, they get all of it, and no one else gets anything from it. The pool never holds miners' funds, so there are no payouts to wait for and no balance that could be lost.

Anyone can run their own pool instead: the node, the pool and their deployment files are all published (see Self-Host).

Difficulty is recalculated every 144 blocks, about every 4.8 hours, instead of Bitcoin's two weeks, so the network adapts quickly when home miners come and go. The adjustment is still capped at a factor of 4 per period, as on Bitcoin.

7. Network and infrastructure

At the time of writing, the network has three public full nodes on three separate servers. New nodes find them automatically, both through DNS seeds (node.twistcoin.org, node1.twistcoin.org, node2.twistcoin.org) and through fallback IP addresses compiled into the software. More independent nodes are the single most useful contribution anyone can make (see Run a node).

All software is open source, on GitLab:

8. Security model and known risks

Proof-of-work security comes from the cost of out-mining the honest network. TwistCoin is a young network with very little hashrate, and it shares its mining algorithm with Bitcoin, the largest SHA256d network in the world. Users should understand what that implies before relying on it.

Majority-hashrate attacks are cheap

Anyone who brings more SHA256d hashrate than the rest of the network combined can rewrite recent blocks, reverse their own payments (double-spend) or refuse to include other people's transactions. Because TwistCoin uses the same algorithm as Bitcoin, a tiny fraction of Bitcoin's hashrate, whether owned or rented by the hour from a hashrate marketplace, is enough to overpower the whole TwistCoin network. Treat confirmations accordingly: wait for many blocks before considering a payment final, and never accept large payments on TwistCoin as if it had Bitcoin's security.

Timestamp manipulation

TwistCoin inherits Bitcoin's difficulty adjustment, including the "timewarp" weakness that Bitcoin mainnet also has today: a miner controlling most of the hashrate can manipulate block timestamps to lower the difficulty and mine coins faster than scheduled. The fix that Bitcoin Core already applies to its test network (BIP94) is not enforced on TwistCoin mainnet, matching Bitcoin mainnet.

Small network, few operators

Three nodes and one public pool are a small network. If hashrate drops sharply, block production slows until the next difficulty adjustment, and the difficulty can only fall by a factor of 4 per period. Today, all three public nodes and the public pool are run by the project itself. That will only change as independent node operators, pool operators and miners join.

Software risk

TwistCoin Core is a fork, and forks can introduce bugs that the original never had. The code audit lists every change made to Bitcoin Core and what was found when reviewing them, including one serious issue that has since been fixed.

TwistCoin makes no promise to remove these risks. It is an experimental network, and it should be used as one.

9. Governance

TwistCoin has no foundation, no token holders' vote and no roadmap of new consensus features. Until there is a community large enough to make real decisions together, TwistCoin follows Bitcoin Core: its decisions and its updates.

• New Bitcoin Core releases, with their bug fixes and security fixes, are merged into TwistCoin Core, keeping only TwistCoin's own changes on top.
• Consensus changes are not invented here. If Bitcoin activates a soft fork, TwistCoin follows it. TwistCoin does not adopt rule changes that Bitcoin itself has not made.
• The only exceptions are changes required by TwistCoin being a different chain (its parameters and network identity), and urgent fixes for bugs in those TwistCoin-specific changes.

If an independent community of miners, node operators and users forms, it will decide how TwistCoin evolves from there.

10. What TwistCoin is not

TwistCoin is not an investment, and nothing in this document is financial advice. No one has sold or will sell TwistCoin to fund the project, there was no ICO, and the project makes no claim about what TWIST is worth or will be worth. It is an open-source, experimental proof-of-work network for people who enjoy running nodes and mining at home. Mine it, run it, read the code, and use it at your own risk.