Blockchain-based recording and querying operations

A computer-implemented system, comprising:

• one or more computers;
• and
• one or more computer memory devices interoperably coupled with the one or more computers and having tangible, non-transitory, machine-readable media storing one or more instructions that, when executed by the one or more computers, perform operations comprising:
• receiving, by an access gateway and from a first service system, user data including a user identifier of a user, wherein the access gateway is configured to interface with multiple different service systems, an identifier hash system, and a blockchain, with the access gateway being distinct from each of the multiple different service systems;
• transmitting, by the access gateway and to the blockchain, a storage transaction that includes the user data;
• receiving, by the access gateway and from the blockchain, a result of the storage transaction having been performed by a storage smart contract that had been previously published by the first service system on the blockchain;
• providing, by the access gateway and to the first service system, the result of the storage transaction;
• receiving, by the access gateway and from a second service system, a user data query, the user data query including the user identifier;
• transmitting, by the access gateway and to the identifier hash system, a hash request for the user identifier under respective different service systems;
• receiving, by the access gateway and from the identifier hash system, a plurality of hash digests for the user identifiers under the respective different service systems, wherein the plurality of hash digests comprises, for each respective service system of the different service systems, a respective hash digest of the user identifier under the respective service system;
• packaging, by the access gateway, the plurality of hash digests of the user identifier under the respective different service systems into a user data query transaction;
• transmitting, by the access gateway and to the blockchain, the user data query transaction;
• receiving, by the access gateway and from the blockchain, an aggregated user score based on a plurality of user scores, wherein the aggregated user score is determined based on a calculation smart contract published on the blockchain, the calculation smart contract configured to perform operations comprising (i) for each respective hash digest of the plurality of hash digests for the user identifier under the respective different service systems, searching the blockchain for respective user scores for the user, and (ii) aggregating the respective user scores to determine the aggregated user score, while preventing disclosure of the user identifier under the respective different service systems;
• and
• providing, by the access gateway and to the second service system, the aggregated user score.

A non-transitory, computer-readable medium storing one or more instructions executable by a computer system to perform operations comprising:

• receiving, by an access gateway and from a first service system, user data including a user identifier of a user, wherein the access gateway is configured to interface with multiple different service systems, an identifier hash system, and a blockchain, with the access gateway being distinct from each of the multiple different service systems;
• transmitting, by the access gateway and to the blockchain, a storage transaction that includes the user data;
• receiving, by the access gateway and from the blockchain, a result of the storage transaction having been performed by a storage smart contract that had been previously published by the first service system on the blockchain;
• providing, by the access gateway and to the first service system, the result of the storage transaction;
• receiving, by the access gateway and from a second service system, a user data query, the user data query including the user identifier;
• transmitting, by the access gateway and to the identifier hash system, a hash request for the user identifier under respective different service systems;
• receiving, by the access gateway and from the identifier hash system, a plurality of hash digests for the user identifiers under the respective different service systems, wherein the plurality of hash digests comprises, for each respective service system of the different service systems, a respective hash digest of the user identifier under the respective service system;
• packaging, by the access gateway, the plurality of hash digests of the user identifier under the respective different service systems into a user data query transaction;
• transmitting, by the access gateway and to the blockchain, the user data query transaction;
• receiving, by the access gateway and from the blockchain, an aggregated user score based on a plurality of user scores, wherein the aggregated user score is determined based on a calculation smart contract published on the blockchain, the calculation smart contract configured to perform operations comprising (i) for each respective hash digest of the plurality of hash digests for the user identifier under the respective different service systems, searching the blockchain for respective user scores for the user, and (ii) aggregating the respective user scores to determine the aggregated user score, while preventing disclosure of the user identifier under the respective different service systems;
• and
• providing, by the access gateway and to the second service system, the aggregated user score.