Creator of solutions for mobile payments startup Square has opened the source code of its service for cold storage of bitcoins.

This was told in his blog, the engineer on security systems in Square, Menghrajani ALok (Alok Menghrajani). Now all the documentation and code from the solution for offline storage of cryptocurrency, called Subzero is available for viewing on Github.

Subzero holds assets user on their behalf using a hardware secure module (HSM). This equipment applies a Square to store encrypted keys from user accounts other payment services. Menghrajani also told that the module can be programmed, and so the company has developed a technology that allows at any time to send bitcoins from hot (online) wallets cold. When returning funds to the hot wallet of the multilateral system will require a signature before a transaction.

In addition, Subzero, you can set certain rules that increase the security level, for example, to allow sending bitcoins from the cold wallet only to addresses accounts belonging to the services Square.

“Because of the HSM program, we will be able to flexibly apply different protocols in the future,” he added Menghrajani.

Recall that the company Square was founded by the head of Twitter, Jack Dorsey (Jack Dorsey). Your first trading service for bitcoins, the company introduced last fall. In June of this year, the service received a license for crypto activities from the Department of financial services new York (DFS), and in August to buy bitcoins via the app the Cash App from Square could the people around US. This led to the fact that for the second quarter of 2018 year sales of main cryptocurrencies in the app has doubled compared with the first quarter. At the end of the same month, the company has patented a payment system that is compatible with any cryptocurrency.