We use protocol buffers to serialize our data for transmission to a pub/sub system like RabbitMQ or Google Cloud Pub/Sub.
Some blockchains provide their own protobuf interfaces, so when possible, we will attempt to use those.
To generate Rust code from our protobuf interface, we use the PROST library. This is a popular library for Rust, and is used by the Solana blockchain with their official "storage" protobuf. We perform this codegen at compile time, using a custom Rust build script: build_proto.rs. This script uses the include! macro to import the protobuf build script from the blockchain-specific configuration. It is expected that each blockchain config will define its own protobuf build script.