Consult the [specification](https://hackmd.io/AC4MEbf8Q12O0P8eSR3xMQ) to build the L1 side of L1 -> L2 message box. Also, there was an early stab before the spec was done [here](https://github.com/AztecProtocol/aztec3-l1-contracts/tree/lh/l1l2-ideas/src/core/messagebridge)
Consult the specification to build the L1 side of L1 -> L2 message box. Also, there was an early stab before the spec was done here