Taproot is the next major upgrade for the Bitcoin protocol
Please upgrade your Bitcoin node by November 12th!
||Taproot transactions usually look the same, even with advanced smart contracts or multiple signers.
||"Schnorr" signatures are used to reduce the data usage and cost of both simple and complex transactions.
||Future improvements to Bitcoin can be cleanly made Taproot-compatible.
||Current Bitcoin transactions continue to work the same.
Bitcoin Core 0.21.0-based Taproot Client 0.1
Other downloads (advanced)
When installing this or any other app, you should verify your download is the authentic program, and not intercepted by a virus.
Always verify the correct digital signature on any downloads to avoid malware.
Bitcoin Core-based Taproot Client is signed by email@example.com and Luke Dashjr.
You should ideally download PGP keys from at least two independent sources and ensure they match.
Click here for a tutorial on how to verify the OpenPGP signature!
- How does Taproot improve privacy?
- First, "Schnorr" signatures allow making multiple signers indistinguishable from a single signer. Using advanced math, the digital signatures of all relevant parties can be added together to produce a single signature valid for the transaction. The coins' key can also optionally be made to commit to a smart contract (one or more), in a manner which is indistinguishable unless the recipients wish to reveal it. Since the outcome of smart contracts is well-defined, ordinarily there is no need to reveal it because both parties can see the outcome and simply agree, therefore utilising a 2-of-2 multiple-signer option instead.
- How is Taproot more efficient?
- Since Bitcoin nodes typically only need to verify a single digital signature for each transaction (see above question on privacy for details on how this is achieved) instead of potentially many, not only do transactions require less high-cost blockchain space, but they also reduce the overall load required to run a node. Additionally, thanks to the ability to add "Schnorr" signatures together, verification can be further optimised by adding all the signatures in the block and verifying them all together once.
- In what way is Taproot upgradable?
- Taproot keys represent a number of multiple-signer combinations as well as one or more smart contracts. Each smart contract specifies a version number, which future upgrades can define to provide a new smart contract language or extensions, while still using the same overall Taproot format (including privacy benefits and being generally indistinguishable from older Taproot transactions and smart contracts).
- What makes Taproot opt-in?
- While all protocol upgrades for Bitcoin require community involvement via running software, and therefore all nodes must upgrade to retain their full security, Taproot does not modify any existing rules of Bitcoin, only adds new ones to the previously reserved and unusable "witness version 1" (not to be confused with the existing "witness version 0" defined by Segwit in 2017). Therefore, old nodes will remain compatible (with security comparable to light wallets), existing bitcoins in circulation today are entirely unaffected, and nobody needs to use Taproot's new features until and unless they choose to.
- Who decided to activate Taproot?
- Taproot was first proposed to the community in 2018, specifics finished in early 2020, and review completed over several months into late 2020. During this time and thereafter, no serious objections to the proposal have been raised, and general sentiment observed in the community has been positive. Therefore, this software has been released to the community with the assumption that there is a general consensus for activating Taproot. However, no mere software release can actually change the Bitcoin protocol, and the final activation can occur only by Bitcoin users adopting this (or compatible) software.
- What if I oppose Taproot?
- The good news is that you do not need to use it (Taproot is an opt-in feature). The bad news is that a lone objection this late is not likely to change anything others do unless it has a very good argument. However, if you do indeed have a good argument, please e-mail it to the Bitcoin development mailing list ASAP. Also note that so long as the rest of the community proceeds toward activation, it will still activate, and you will need to upgrade yourself to retain full security. If your objection is firm enough, regardless of reason, you can, however, create or support a counter-proposal to prevent activation of Taproot (see BIP 8 for details).
- Why do I need to upgrade for Taproot?
- Bitcoin is a decentralised system, with the rules and security enforced by its users. Without an economic majority of users enforcing the new Taproot rules, it cannot be safely used by anyone.
- What happens if I don't upgrade in time?
- If you have not upgraded before Taproot activates (around November 12th), your node will no longer be fully secure and you may become vulnerable to certain attacks. In such a case, your node would be trusting and relying on miners to protect you until you do upgrade.
- Do only miners need to upgrade?
- No. Miners play an important role in Bitcoin by preventing "double spending", but the protocol is primarily enforced by non-miners.
- What role do miners have in activating Taproot?
- In order to ensure all users have upgraded, softforks typically need a long period of time before activation - over a year. However, so long as a significant majority of users have upgraded, the network security overall can be ensured, while miners can be entrusted with the protection of only the remaining minority who need more time. Therefore, if miners upgrade sooner, a shorter time period can be used.
- Is this a User-Activated SoftFork (UASF)?
- No. This activation uses BIP 8 to ensure a safe and clean activation coordinated by miners. It is therefore a Miner-Activated SoftFork (MASF).
Taproot Client Software
- Who maintains the Taproot Client software?
- The software code has been written and reviewed by several Bitcoin Core developers. The releases are, however, maintained by three community members, Bitcoin Mechanic, Shinobi, and stortz. Luke Dashjr has helped advise and make sure things get done properly and safely.
- How is the software different from regular Bitcoin Core?
- Unmodified Bitcoin Core includes the code to implement Taproot, but disabled. When Taproot activates, it will not enforce the new rules, and may fall out of consensus. Update 2021-06-29: Bitcoin Core 0.21.1 has been released with Taproot activation enabled. It is still recommended to run the dedicated Taproot Client release if you wish to show your support explicitly, but upgrading to 0.21.1 or later is sufficient to remain secure.
* Activation is based on Bitcoin block height, so calendar dates are approximate