Spiderchains: A Proof Of Stake Second Layer

This is an extension to my previous article series discussing the different sidechain proposals that exist. Those articles can be found here: Spacechains, Spacechain Use Cases, Softchains, Drivechains, Federated Chains, and Trade Offs Of Sidechains.

Botanix Labs has proposed a completely new sidechain design recently, called spiderchains, for the purposes of porting the Ethereum Virtual Machine to a platform anchored to the Bitcoin network. The architecture is a pretty large deviation from most prior proposals for concrete designs. Firstly, it does not involve miners directly in consensus or use merge-mining in any of its variant forms. Secondly, it uses multisig and escrow bonds to create a second layer proof-of-stake system on top of Bitcoin. Third, it does not require any changes to Bitcoin in order to deploy.

The first thing to clarify is that, technically speaking, the spiderchain isn't really the sidechain. Any sidechain deployed utilizing spiderchains would sit "above" the spiderchain which sits above the base layer on the mainchain. Sidechain blocks would be produced independently by the stakers (referred to as orchestrators in the paper) in the consensus system. The spiderchain, rather than being the actual sidechain, is a sort of collateral layer facilitating the custody of users' funds and stakers bonds on the mainchain. Think of it like the middle of the sandwich between the sidechain and the mainchain.