CommerceBlock is releasing Mercury Layer today, an improved version of their variation of a statechain. You can read a longer form explanation of how their Mercury statechains work here. The upgrade to Mercury Layer represents a massive improvement against the initial statechain implementation, however unlike the initial Mercury Wallet release, this is not packaged as a fully consumer ready wallet. It is being released as a library and CLI tool other wallets can integrate. Here’s a quick summary of how they work:

Statechains are essentially analogous to payment channels in many ways, i.e. they are a collaboratively shared UTXO with a pre-signed transaction as a mechanism of last resort…

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