According to Odaily Planet Daily, StarkWare used its new STARK validator in the Bitcoin test environment Signet network and used OP_CAT technology. OP_CAT is a proposed upgrade of Bitcoin that aims to bring Ethereum-style "smart contract" programmability.

While OP_CAT has no shortage of supporters, it is still in the early stages of gaining the consensus needed to be incorporated into the Bitcoin Core software. “StarkWare publicly supports the approval of this proposal as it will bring clear benefits to the Bitcoin community as well as the broader blockchain ecosystem,” the company said in a press release.