xx Network: Sprint Toward Mainnet
ChainSafe R&D partnered with xx Network on a 5-week sprint to mainnet, bringing Substrate expertise, code reviews, and tests to strengthen its privacy-focused blockchain and cMix mixnet.
Written by Willem Olding
ChainSafe R&D is ChainSafe’s internal applied research and development arm. We provide high-quality research. This research explores new technical and business areas. It supports larger projects inside and outside ChainSafe. The ChainSafe R&D team has completed and still maintains projects with teams like Gitcoin and Polygon. For example, we worked on Gitcoin's decentralized Grants and Polygon's v3 spec.
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 work helped the team quickly develop custom chain logic for xx Network. They built on a tested and audited codebase in Substrate.
ChainSafe has long supported Substrate. Some of our projects include ChainBridge, which connects Substrate and Ethereum chains. We also work on the PINT parachain and our own framework called Gossamer, which is compatible with runtimes. We jumped at the chance to help another promising project make it through the final hurdles. Supporting xx Network shows our growing skills as Substrate developers and code reviewers. This work is in an exciting area of 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 privacy at the network layer by routing messages through mixing nodes. These nodes erase any link between the sender and the receiver. cMix needs global coordination and rewards for mix-nodes. The xx blockchain solves both of these problems. 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. The network layer privacy from xx Network will power xx messenger. This is a private off-chain messaging app. It will be available on major mobile platforms soon after the 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. The pre-sale for xx coin started on Ethereum as an ERC-1404 token. The network used Polkadot’s Claims module to let users get 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!). We added benchmarking to automatically find 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.
About ChainSafe
ChainSafe is a leading blockchain research and development firm specializing in protocol engineering, infrastructure development, co-development and web3-enabled gaming.
Alongside its contributions to major ecosystems such as Ethereum, Polkadot, Filecoin, ChainSafe creates solutions for developers and teams across web3.
As part of its mission to build accessible and improved tooling for developers, ChainSafe embodies an open source and community-guided ethos to advance the future of the internet.