Attest with Ethereum

The site, attest-with.eth, allows one or more Ethereum accounts to attest a small amount of text.

What's the small amount of text? It could be anything. For example, I could write "My name is X and my ethereum account is at 0x9b2055d370f73ec7d8a03e965129118dc8f5bf83" and then sign this with my 0x9b2055d370f73ec7d8a03e965129118dc8f5bf83 account to which I hold the private key, and thereby attest to the statement in the text.

While me signing my own statement like that is fine for attesting to the original statement, the real power comes when others attest to the same statement. If many other people attest to the same statement, it is likely to hold some weight. Of course, this depends on the weight carried against those who attest, but these will gain prominence over time as we build a 'web of trust.'

Why just a small amount of text?

In theory, you can sign anything, be that some structured JSON or a JPEG or whatever else. But, Web3 wallets don't allow for users to easily see what they sign unless it's just some small amount of text. Taking inspiration from the 'Sign in with Ethereum' movement, where a small amount of text is signed to let people authenticate themselves, we here do the same by letting people sign a small amount of text to attach their signature to this. The structure of the text, if any, is application dependent.

All off-chain

There is no need to put everything on a blockchain. In fact, it's likely unwanted as the text you attest might hold personal data or other sensitive information. The point is not to put data on-chain, but to leverage Web3 technologies and wallets to let people do more than just sign on-chain transactions. When attesting a small amount of text, the output can be downloaded as an attest.json file. If you want to provide a statement signed with your public Ethereum account, do so and pass the attest.json file on to whomever is interested in this attestation. They can then themselves upload the file to attest-with.eth to verify the signatures, or do so off-line, and optionally add on their own attestation if they so wish.

Web app

This repo contains the code for the web app. Beyond serving some static files there is no backend requirements as it's all done within the browser.

It's a React app, following a typical setup. You can start the app locally with npm start.

Unlicensed and my motivation for building this

The code in this repo is published as public domain code, mainly because it doesn't do much more than pull together existing technology in obvious ways. Never before, thanks to blockchain and Web3 wallets, have so many people generated their own set of public/private keys. We now have a setup where publishing your public key is easier than ever before. While the reasons why so many people do this is often motivated by short term speculation in cryptocurrencies, it provides a strong platform on which we can build.

What I would hope this web app adds to the domain is attest.json, a structure for including cryptographic signatures tied to some content. The structure of attest.json is simple by design, which is different to some other efforts out there, like those of verifiable credentials.

Much like the 'Sign in with Ethereum' movement looks to standardize on the signing of simple text for the purpose of authenticating users of a web app, attest.json is an attempt at providing a simple structure for attestations. Hopefully this can help drive the adoption of self-sovereign identity.

attest.json

The attest.json file contains 4 top level fields:

comment: Simply there to add auxiliary detail

content: A string of text signed by accounts

attestations: An array of zero or more attestations, each attestation consisting of an account and a signature

version: attest.json schema version, currently 1

Example attest.json:

{
    "comment": "Downloaded from attest-with.eth - Verify at https://attest-with.eth.link",
    "content": "This is an example of attest.json, signed by two different accounts.",
    "attestations": [
        {
            "account": "0x2c89797CC766603812bAe16106633bee446654F5",
            "signature": "0x223c3383a9b6b0a8751fd29c23b87061942f424a787d901a8808e005acf85e8225f6f1be9952b2a8f8a87b19b56df65d587f71c539b3ec0adf2da7a50c9c55271c"
        },
        {
            "account": "0xB68cC68fB8DE5400A281311f4D2bb1591cE26891",
            "signature": "0xeb8ded20441bc9e0d18c8bb3981b0bb1b2228611db4e171424a735b72d83de494c0d1144c382cefa6c826d0ab6e881b1a88150b38fb63917bc0f113e842676661b"
        }
    ],
    "version": 1
}