Scheduled (Delayed) Transaction Broadcast

The feature request for scheduled transaction broadcast in Bitcoin Core has sparked an exploration into its feasibility and potential implementation. This function would allow users to schedule transactions to be broadcast to the bitcoin network at a later time, rather than immediately. The purpose behind this capability includes desires to mask the actual time of transaction creation or to cater to future conditions that cannot be adequately addressed through bitcoin scripts.

Scheduled Transaction Broadcast proposes that the bitcoin node would accept transactions designated for future broadcast, storing them until the specified time. This approach introduces flexibility for transactions based on absolute time or block height but does not guarantee delivery. The feature would rely on a new RPC, schedulerawtransaction, which mirrors the syntax of sendrawtransaction but with functionality geared towards scheduling. Transactions managed under this feature would be stored in a distinct memory structure and persisted in a separate file to maintain consistency across restarts.

Concerns and queries about this feature include its history of consideration within the development community, potential conflicts with existing features—specifically the broadcasting over temporary connections (PR 29415)—and any significant obstacles that could undermine its implementation or effectiveness. It's acknowledged that since broadcasting is deferred, the outcome of the transaction broadcast, whether successful or encountering errors, won't be immediately known. Users would need to monitor the bitcoin network subsequently to ascertain the status of their transactions.

This initiative is still in a conceptual phase, with a prototype developed to test the viability of such a feature. Feedback and comments are being solicited from the broader development community to identify any past attempts to introduce similar functionalities, pinpoint possible issues, and gather suggestions that could enhance the feature's design and utility.