NOCUST is a Commit-Chain or non-custodial side-chain to scale Blockchains through layer 2.
We are very excited to release today an updated version of the academic paper, adding passive delivery (recipients can now be offline), adding an experimental evaluation with gas costs etc, explaining in-depth the collateral requirements (for instant finality) and having a new way to perform provably consistent checkpoints with zkSNARKS (also experimentally evaluated).
The paper can be found here:
https://eprint.iacr.org/2018/642.pdf
Happy to discuss it.