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

# Block Builder

> A specialized participant that constructs candidate blocks or transaction bundles for proposers.

# Block Builder

A specialized participant that constructs candidate blocks or transaction bundles for proposers.

## Definition

A specialized participant that constructs candidate blocks or transaction bundles for proposers.

## Why it matters

MEV concepts explain how transaction ordering can create economic opportunities and risks.

## Related knowledge

* [Mempool](/generated/v2/glossary/mempool) — term
* [Searcher](/generated/v2/glossary/searcher) — term
* [Transaction Ordering](/generated/v2/glossary/transaction-ordering) — term

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**Canonical knowledge ID:** `glossary:block-builder`