This often requires creating a new blockchain or sidechain to an existing one. However, a new proposal suggests an alternative method that does not require launching a separate blockchain or sidechain. This new approach can achieve similar security levels to federated sidechains, but it also offers additional benefits to privacy and smart-contract-patching. The proposal involves using Bitcoin's script language to implement the smart-contract functionality. By doing so, users can create their own custom transaction types without having to modify Bitcoin's core code. The proposed method uses a combination of OP_CHECKLOCKTIMEVERIFY (CLTV) and OP_CSV (CHECKSEQUENCEVERIFY) to create a new transaction type called "Vault Transactions". These transactions allow users to lock funds for a specified period and then release them only if certain conditions are met. This is useful for applications such as time-locked payments and escrow services. Furthermore, the new method allows for the creation of "Patchable Smart Contracts", which can be updated by users without requiring a hard fork of the blockchain. This is achieved through the use of a "patching transaction" which modifies the original smart contract. Overall, this proposal offers a new and innovative approach to implementing smart contracts without the need for a separate blockchain or sidechain. It provides enhanced security and privacy features while also allowing for the creation of patchable smart contracts.