Layer 2 developer StarkWare has used its new STARK validator and OP_CAT technology in the Bitcoin testing environment Signet network, OP_CAT a proposed upgrade to 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 integrate into Bitcoin's core software. In a press release, the company said: "StarkWare publicly supports the approval of this proposal as it will pr...