---
title: "client/flashblocks"
description: "Flashblocks state management — WebSocket streaming, pending state, EVM re-execution."
source: https://basehub.org/crates/client/flashblocks/
---
import { LinkCard } from '@astrojs/starlight/components';

## Overview

The `base-flashblocks` crate manages the core flashblocks state. It handles:

- WebSocket streaming of flashblock updates from the builder
- Pending state cache for preconfirmed transactions
- EVM re-execution for state queries against the pending block
- The `pending` tag support for standard Ethereum JSON-RPC methods

This is the crate that powers the [Flashblocks RPC](/specifications/flashblocks/).

## Source

<LinkCard title="View source on GitHub" href="https://github.com/base/base/tree/main/crates/client/flashblocks" />