> ## Documentation Index
> Fetch the complete documentation index at: https://docs.optimism.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Building

This section offers in-depth documentation into the various `op-alloy` crates.
Some of the primary crates and their types are listed below.

* [`op-alloy-consensus`](https://crates.io/crates/op-alloy-consensus) provides [`OpBlock`](https://docs.rs/op-alloy-consensus/latest/op_alloy_consensus/type.OpBlock.html),
  [`OpTxEnvelope`](https://docs.rs/op-alloy-consensus/latest/op_alloy_consensus/transaction/enum.OpTxEnvelope.html), [`OpReceiptEnvelope`](https://docs.rs/op-alloy-consensus/latest/op_alloy_consensus/enum.OpReceiptEnvelope.html),
  and more.
* [`op-alloy-rpc-types-engine`](https://crates.io/crates/op-alloy-rpc-types-engine) provides the
  [`OpPayloadAttributes`](https://docs.rs/op-alloy-rpc-types-engine/latest/op_alloy_rpc_types_engine/struct.OpPayloadAttributes.html).