Starkex

The starkex contracts are:

• deployed at 0x6cB3EE90C50a38A0e4662bB7e7E6e40B91361BF6
• and sit behind the upgradable smart contract at 0x47312450b3ac8b5b8e247a6bb6d523e7605bdb60.

By looking at the Constructor Arguments section of the implementation contract (which might be outdated at the moment of this writing, as the implementation contract is upgradable) one can see where the subcontracts are deployed:

• bootloaderProgramContract: 0x5d07afFAfc8721Ef3dEe4D11A2D1484CBf6A9dDf
• memoryPageFactRegistry_: 0xFD14567eaf9ba941cB8c8a94eEC14831ca7fD1b4
• cairoVerifierContracts]: 0x217750c27bE9147f9e358D9FF26a8224F8aCC214,0x630A97901Ac29590DF83f4A64B8D490D54caf239,0x8488e8f4e26eBa40faE229AB653d98E341cbE57B,0x9E614a417f8309575fC11b175A51599661f2Bd21,0xC879aF7D5eD80e4676C203FD300E640C297F31e3,0x78Af2BFB12Db15d35f7dE8DD77f29C299C78c590,0xe9664D230490d5A515ef7Ef30033d8075a8D0E24,0x03Fa911dfCa026D9C8Edb508851b390accF912e8
• hashedSupportedCairoVerifiers: 3178097804922730583543126053422762895998573737925004508949311089390705597156
• simpleBootloaderProgramHash: 2962621603719000361370283216422448934312521782617806945663080079725495842070

Note: The different verifier contracts correspond to the different layouts that are supported for Cairo (see the Builtins and Layouts of Cairo section of the book).

Somewhat outdated implementations live on Github at starkware-libs/starkex-contracts.

They implement the SHARP (SHARed Prover) verifier, which allows us to verify SHARP proofs on Ethereum.

Note: A number of contracts refer to “GPS” which is the old name for SHARP (general-proving service).

Any application on Ethereum that wants to use Cairo can make use of this service to verify proofs. The flow is split in two parts:

1. The proof is sent to the SHARP service, which verifies it and returns a fact.
2. The application can check that the fact has been verified.

We explain what “facts” are in facts section.