# Saya Settlement This document describes the implementation of `Saya`, an addition to the Dojo toolchain, which serves to settle Katana sequencers to a settlement layer. The document consists of several phases, progressively extending the support for additional settlement chains and data availability providers. ![2023-11-28 12.09.32](https://hackmd.io/_uploads/S1WY5BQSp.jpg) ## Stage ### Generating the trace and state diff This initial task entails the scaffolding of the Saya service. A rust service that runs along side a Katana instance. Saya is responsible for pulling blocks from Katana, executing them and generating the corresponding execution trace and state diff. This should probably extend [the existing SNOS implementation](https://github.com/keep-starknet-strange/snos/tree/lucas/continue). In order to generate the execution trace and state diff, the [Starknet OS](https://hackmd.io/YCwgt6NwRTyKgqc5UcSNHA) needs to be executed. There is an existing effort to support this for Madara. It expects [the following input](https://github.com/keep-starknet-strange/snos/blob/f584818cfb3b4c58aa85b4a2879d248e553b6c29/src/io/mod.rs#L17-L34): ```rs pub struct StarknetOsInput { pub contract_state_commitment_info: CommitmentInfo, pub contract_class_commitment_info: CommitmentInfo, pub deprecated_compiled_classes: HashMap<Felt252, DeprecatedContractClass>, pub compiled_classes: HashMap<Felt252, Felt252>, pub contracts: HashMap<Felt252, ContractState>, pub class_hash_to_compiled_class_hash: HashMap<Felt252, Felt252>, pub general_config: StarknetGeneralConfig, pub transactions: Vec<InternalTransaction>, pub block_hash: Felt252, } ``` This information should be exposed from Katana as necessary, potentially implementing new RPC endpoints if needed. It is worth an intial exploration into how Madara is planning to export this data. Currently, there are some limitations with Cairo VM which requires the legacy python Cairo VM in order to execute the Starknet OS, namely, cairo-vm cannot execute two or more Cairo programs using the same memory. This is something the Lambda team is working on. ### Fact registration on Starknet As an incremental step, we would like to support settling facts to Starknet with verification left to future work. To do so, we should port the existing [Solidity Fact Registry](https://etherscan.deth.net/address/0x92043f243831a9b0aF379F0BED8513fABDAbE513#code) into Cairo, deploy it to Starknet / Testnet, and implement logic in Saya to register facts. ### Verification on Starknet Onchain verification on Starknet is blocked by the Cairo verifier implementation work, currently underway by the Heredotus team. ### Verification on EVM chains Redeploy the Fact Regsitry and verifier stack to EVM chains. Create a simple to do so inside the Dojo repo. Update Saya to support settlment to EVM chains.
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DIP-87: Layers of Dope

Summary:The proposal focuses on deploying ‘Roll Your Own’ (RYO), a game, as a Layer 3 (L3) application on top of the Optimism network. This implementation will utilize zero-knowledge proofs (zkproofs) for game round aggregation and settlement on Optimism. The proposal also includes the development of a bridge between Layer 2 (L2) and L3, with PAPER tokens being used for transaction fees. In exchange for these developments, the proposal seeks 50k OP tokens from the Optimism network.

1/8/2024
Supporting webauthn for transaction validation

WebAuthn is an industry standard specification for accessing Public Key credentials. It defines a set of APIs and interfaces for securely generating keypairs that can subsequently be used for user authentication. The specification is widely supported (Apple, Google, Microsoft) and provides an array of configuration options, each with different usability and security tradeoffs. In the most usable configuration, platform authentications (Face ID, finger print, ect) provide a simple way for users to securely generate + manage their keypair. Many platforms today include secure elements which can be leveraged through the webauthn api. Passkeys further improve user experience by transparently synchronizing credentials across devices and supporting recovery through the root platform account (i.e. iCloud). In the most secure configuration, roaming authentications allow specialized hardware to generate credentials and assertions, allowing users to manage their credentials using FIDO2 compliant devices such as Yubikeys or a Ledger (coming soon). This massive shift in authentication logic is being catalyzed by existing software and hardware providers that represent almost the entirety of the device ecosystem today. Supporting Webauthn credentials allows Starknet to capitalize this momentum, to provide a massive improvement in blockchain usability and, to provide a path for mainstream user adoption. To summarize:

11/10/2022
Supporting webauthn on Starknet

WebAuthn is an industry standard specification for accessing Public Key credentials. It defines a set of APIs and interfaces for securely generating keypairs that can subsequently be used for user authentication. The specification is widely supported (Apple, Google, Microsoft) and provides an array of configuration options, each with different usability and security tradeoffs. In the most usable configuration, platform authentications (Face ID, finger print, ect) provide a simple way for users to securely generate + manage their keypair. Many platforms today include secure elements which can be leveraged through the webauthn api. Passkeys further improve user experience by transparently synchronizing credentials across devices and supporting recovery through the root platform account (i.e. iCloud). In the most secure configuration, roaming authentications allow specialized hardware to generate credentials and assertions, allowing users to manage their credentials using FIDO2 compliant devices such as Yubikeys or a Ledger (coming soon). This massive shift in authentication logic is being catalyzed by existing software and hardware providers that represent almost the entirety of the device ecosystem today. Supporting Webauthn credentials allows Starknet to capitalize this momentum, to provide a massive improvement in blockchain usability and, to provide a path for mainstream user adoption. To summarize:

9/13/2022
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