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

# S-two 🚀

> Learn about StarkWare's next-generation S-two prover and how Atlantic leverages it for high-performance proof generation

## What is S-two?

**S-two** is [StarkWare's next-generation STARK prover](https://www.starknet.io/blog/s-two-is-live-on-starknet-mainnet-the-fastest-prover-for-a-more-private-future/), representing a major breakthrough in zero-knowledge cryptography. As the world's fastest prover, S-two is now live on Starknet mainnet and powers Atlantic's proof generation capabilities.

S-two is **fully open-source** and built from the ground up to deliver unprecedented performance improvements over its predecessor, Stone, which secured StarkEx and Starknet for the past six years.

## Key Features

| Feature                      | Description                                                                                                                                                                                 |
| ---------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| World's Fastest Prover       | S-two delivers an unprecedented leap in proving speed, generating proofs up to an order of magnitude faster than its predecessor, Stone, and outperforming every other prover in its class. |
| New Cryptographic Foundation | It is built on cutting-edge Circle STARKs technology and utilizes the M31 field (a small, highly efficient prime field optimized for performance).                                          |
| Open-Source                  | S-two is a fully open-source prover, allowing the community to examine its codebase and contribute to its continuous development.                                                           |
| Implementation               | It is implemented in Rust for optimal performance and supports both the Cairo programming language and direct AIR (Algebraic Intermediate Representation) definitions.                      |

## S-two Integration with Atlantic

Atlantic leverages S-two's exceptional performance to provide:

### Enhanced Proof Generation

When you submit queries to Atlantic, S-two's optimized proving engine processes your Cairo programs and traces with:

* **Faster turnaround times** from trace submission to verified proof
* **Lower computational overhead** reducing overall infrastructure costs

## Getting Started with S-two on Atlantic

To use S-two on Atlantic, submit your query with `sharpProver` set to `stwo`.

<Card title="Submit Your First Query" icon="rocket" href="/atlantic-api/sending-query">
  Learn how to submit queries
</Card>

<Warning>
  **L1 Only**: S-two is currently supported only for L1 verification. Support for L2 (integrity verifier) will be added soon.
</Warning>

## Learn More

* [S-two Technical Documentation](https://github.com/starkware-libs/stwo) - Official S-two GitHub repository
* [Starknet S-two Announcement](https://www.starknet.io/blog/s-two-is-live-on-starknet-mainnet-the-fastest-prover-for-a-more-private-future/) - Official launch announcement