> For the complete documentation index, see [llms.txt](https://docs.infinitetrading.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.infinitetrading.io/introduction/what-is-ethereum/scaling-solutions/what-is-optimism.md).

# What is Optimism ?

### Fast, stable, scalable Ethereum.

OP Mainnet is a fast, stable, and scalable L2 blockchain built by Ethereum developers, for Ethereum developers. Built as a minimal extension to existing Ethereum software, OP Mainnet's EVM-equivalent architecture scales your Ethereum apps without surprises. If it works on Ethereum, it works on OP Mainnet at a fraction of the cost.

#### OP Mainnet goes Superchain

The Superchain project seeks to maximize interoperability and composability between different chains using the OP Stack, and integrate siloed L2s into a single, cohesive layer.

OP Stack

The modular code powering OP Mainnet and the Superchain.

[View docs](http://stack.optimism.io/)

The Superchain

Building towards a unified future that doesn’t fracture our ecosystems, our applications, or our ability to work together.

[Get in touch](https://forms.monday.com/forms/055862bfb7f4091be3db2567288296f8?r=use1)

**Developer resources**

Everything you need to get started building on OP Mainnet, all in one place.