Swift Activation - CTV

Swift Activation - CTV

Original Postby Anthony Towns

Posted on: January 3, 2024 08:36 UTC

The recent discussions about Bitcoin's development have highlighted two significant proposals: CheckTemplateVerify (CTV) and AssumeUTXO (APO).

These proposals aim to refine specific functionalities within Bitcoin, which are anticipated to be beneficial for wallet and layer-two software. The process of making incremental consensus changes to incorporate new features is viewed as cumbersome, suggesting a preference for broader, more inclusive strategies that could integrate multiple enhancements simultaneously.

AssumeUTXO's design philosophy shares elements with Satoshi's ANYONECANPAY method, notably the feature that allows adding additional inputs to transactions. However, this design approach has been scrutinized, leading to a debate over whether it might be flawed both for ANYONECANPAY and APO. Critics argue that fixing the number of inputs in a transaction could be advantageous. By setting input numbers, users can minimize third-party interference in their transactions and mitigate the risks associated with replace-by-fee (RBF) pinning. An important benefit of this fixed input approach is the elimination of transaction identifier (txid) malleability – a known issue in Bitcoin transactions. For further details on the technicalities, interested readers can review the pull request on the Bitcoin Improvement Proposals (BIPs) repository found at