> ## Documentation Index
> Fetch the complete documentation index at: https://base-a060aa97-eb-mini-app-ia-overhaul.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Differences between Ethereum and Base

Base is built on the [Bedrock](https://stack.optimism.io/docs/releases/bedrock/explainer/) release of the [OP Stack](https://stack.optimism.io/), which is designed from the ground up to be as close to Ethereum as possible. Because of this, there are very few differences when it comes to building on Base and Ethereum.

However, there are still some minor discrepancies between the behavior of Base and Ethereum that you should be aware of when building apps on top of Base.

These minor differences include:

* [Flashblocks](https://docs.base.org/base-chain/flashblocks/apps)
* [Opcodes](https://stack.optimism.io/docs/releases/bedrock/differences/#opcode-differences)
* [Blocks](https://stack.optimism.io/docs/releases/bedrock/differences/#blocks)
* [Network specifications](https://stack.optimism.io/docs/releases/bedrock/differences/#network-specifications)
* [Transaction costs](https://stack.optimism.io/docs/releases/bedrock/differences/#transaction-costs)