Sharder

Sharder is a dApp which gives the ability to split a document into several shards and share those with a specific number of people that you select.

The shards by themselves are useless, but put together you can reconstruct the original document. Sharder uses the Shamir Secret Sharing algorithm to achieve this. This way, you can increase redundancy by sharing some shards with people that you trust without them being able to have access to the document on their own.

On the same platform, you can combine the shards in your possession to reconstruct a file. Sharder produces an attestation of the sharding configuration available for everyone, but without disclosing any private information about the shards themselves.

This project is a dApp, which means that it is mostly frontend code made with the React framework and the Material UI library. We used the TypeScript programming language for the development. We reimplemented the Shamir Secret Sharing made originally by the Hashicorp team from the Vault project.

The following sponsors really helped taking Sharder to the next level 🚀

• 🦊 Of course, users need to connect to the platform to be able to perform many tasks. This is where we used the Metamask SDK, which provides a very developer-friendly approach to manage web3 user sessions.

• ⓧ As a user can share the shards he made by sending those to a set of other users, we used XMTP and more specifically the conversations and remote content sharing features to distribute the shards across the users.

• 🔍 We ensured that the users who will potentially receive shards have a working XMTP Identity using Airstack.

• ⍙ Finally, EAS gives us the ability to create and publish on-chain attestations about the sharding configuration.