Originally posted on Medium
ChainSafe R&D is ChainSafe’s internal applied research and development arm. We provide high quality research to explore new technical and business frontiers in support of larger projects both internal and external to ChainSafe. The ChainSafe R&D team has previously completed (and in many cases continue to maintain) engagements with teams like Gitcoin (“decentralized Grants”), and Polygon (“v3 spec”), to name a few.
ChainSafe has recently concluded a 5-week sprint supporting development of the xx Network as they move toward their mainnet release.
The xx Network blockchain is built using Parity’s Substrate framework in Rust. This has allowed the team to make rapid progress developing the custom chain logic for xx Network while building on top of a battle tested and audited codebase in Substrate.
ChainSafe has been a long time supporter of Substrate with some of our projects including ChainBridge (a flexible solution for bridging Substrate and Ethereum chains), the PINT parachain, and our own runtime-compatible framework Gossamer. We jumped at the chance to help another promising project make it through the final hurdles. Supporting xx Network also highlights our growing capabilities as Substrate developers and code-reviewers in an extremely exciting space in blockchain development.
Network-layer privacy vs. Transaction-level privacy
In its first form, the xx Network blockchain serves to support and incentivize the already operational mixnet protocol cMix. Mixnets provide network-layer privacy by routing messages between mixing nodes, which effectively erase any link between the sender and the receiver. cMix requires global coordination and incentivization for mix-nodes, and the xx blockchain solves both of these! Nodes participating in consensus must also be active mix-nodes. Their performance as mixers directly affects what they can expect to receive as block rewards. You can learn more in the cMix whitepaper.
Network-layer privacy has seen much less attention in the crypto space compared with transaction-level privacy, as present in other blockchain projects such as ZCash and Monero. However, both will be required for us to one day be able to transact with total privacy, which includes end-to-end encryption and metadata shredding. Moreover, the network layer privacy offered by xx Network will power xx messenger, a private off-chain messaging app available on major mobile platforms shortly after mainnet launch.
The first release of the xx chain adds on-chain logic to support the operation of cMix as well as the unique economic logic for xx coin. Since the pre-sale for xx coin was instantiated on Ethereum as an ERC-1404 token, the network adapted Polkadot’s Claims module in order to allow users to receive their native xx coins at mainnet launch. Furthermore, xx Network plans to use ChainBridge to allow users to swap wrapped ERC20 xx coins on Ethereum to their native form on the xx blockchain.
Contributions from ChainSafe
As part of the engagement, all new additions were evaluated line-by-line, tests written to ensure full coverage (over 100 tests were added in total!), and benchmarking added to automatically derive weights for all externally callable functions. Several major issues were found and subsequently fixed by the team. Progress! The full report of the review will be available once the codebase is released to the public.
We look forward to the future of xx Network and the value they will bring to the blockchain ecosystem with their privacy preserving technology.
Acknowledgments
Thank you to Tim Ho and Bernardo Cardoso. Your contributions were invaluable to the making of this article.