announcement · educative · zk

Announcing the S-two Book

Jason Park, Varun Thakore November 11, 2025 1 min

S-two Book

We are excited to announce that we partnered with Starkware to create the S-two book! (Link to repo: *.mdx files and *.md files)

S-two is Starkware's next-generation prover with state-of-the-art performance thanks to its implementation of Circle STARKs over the Mersenne31 prime field. It is also flexible enough to support proving custom circuits such as various VMs and ML inference.

We encourage anyone who is interested in the following topics to check it out:

Learning how to write AIRs using the S-two prover
Learning how the Cairo AIR is implemented in S-two
Learning how S-two implements Circle STARKs

Tip

If you need an introduction to Circle STARKs, check out our series of blog posts: Part I, Part II, Part III.

Keep reading

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