The invention relates to distributed ledge technologies such as consensus-based blockchains. Methods for causing an injection of a serialized previous transaction into a locking script are described. The invention is implemented using a blockchain network, which may be, for example, a Bitcoin blockchain. A first transaction to validate is received at a node in a blockchain network, with the first transaction including a first script. The first script, as a result of being executed, causes the node to at least obtain a first set of field values corresponding to the first transaction and obtain a second set of field values corresponding to a particular transaction. A second transaction is obtained, with the second transaction having been validated and including a second script. The second script, as a result of being executed, causes the node to at least obtain the first set of field values and the second set of field values of the particular transaction supplied as a result of execution of the first script, extract a transaction identifier from the first set of field values, and determine, based at least in part on the second set of field values, that the particular transaction corresponds to the transaction identifier. The first transaction is validated by executing the first script and the second script.