Setting Up Decentralized Social Credential Verification

Decentralized social credential verification moves identity attestations from centralized databases to public blockchains. Protocols like Ethereum Attestation Service (EAS) and Verax allow entities to issue on-chain attestations—tamper-proof records that verify a user's social attributes, such as membership in a DAO, completion of a course, or validation by a trusted community. These credentials are stored in a user's smart contract wallet or identity primitive like ERC-725, creating a portable, user-owned reputation graph that is interoperable across Web3 applications.

The core technical workflow involves three parties: the issuer (a protocol or community), the subject (the user receiving the credential), and the verifier (an application checking the credential). An issuer creates an attestation schema on-chain, defining the data structure for the credential. When a user meets the criteria, the issuer calls a function to create the attestation, signing a transaction that links the credential to the user's Ethereum address or Decentralized Identifier (DID). This record is immutable and publicly verifiable by anyone with the attestation's unique UID.

To implement a basic verification check, a dApp's smart contract or frontend queries the attestation registry. Using EAS, you can verify an attestation with a view function call. For example, a gated community might check for a specific attestation schema UID linked to a user's address before granting access. The code snippet below demonstrates a simplified Solidity check for an EAS attestation:

solidityCopy
// Example: Contract checking for an active attestation
interface IEAS {
    function getAttestation(bytes32 uid) external view returns (Attestation memory);
}

function checkMembership(address user, bytes32 schemaUID) public view returns (bool) {
    // Construct the attestation UID from user and schema
    bytes32 attestationUID = keccak256(abi.encodePacked(schemaUID, user));
    
    try IEAS(easAddress).getAttestation(attestationUID) returns (Attestation memory att) {
        // Check if attestation is valid and not revoked
        return (att.revocationTime == 0);
    } catch {
        return false;
    }
}

Key considerations for developers include privacy, revocation, and sybil-resistance. While attestations are on public chains, using zero-knowledge proofs (ZKPs) via protocols like Sismo or Semaphore allows users to prove credential ownership without revealing their underlying identity or linkable wallet address. Revocation mechanisms are crucial; issuers must be able to invalidate credentials if needed, which is a native feature in attestation registries. To combat sybil attacks, many systems layer on proof-of-personhood solutions like Worldcoin or BrightID as a root attestation.

The ecosystem is evolving with competing standards. EIP-712 is often used for off-chain signing of attestation data, while EIP-5792 proposes a standard for wallet-held credentials. When designing a system, evaluate the trade-offs between using a universal registry like EAS versus a dedicated, application-specific smart contract. Universal registries offer better interoperability, while custom contracts provide more flexibility in logic and data handling. Always audit the security model of the attestation protocol you integrate, as it becomes a central trust anchor for your application.

Practical use cases are already live. Gitcoin Passport aggregates multiple attestations into a single score for sybil-resistant voting. Optimism's AttestationStation allows any user to issue attestations on Optimism, fostering a native reputation layer. To get started, developers can experiment on testnets: deploy a schema via the EAS Explorer or Verax's testnet portal, issue attestations to test addresses, and build a simple React frontend with the EAS SDK to scan and verify them, forming the foundation for decentralized social graphs.

Decentralized social verification uses blockchain-based protocols to create portable, user-owned credentials that prove aspects of your identity or reputation. Unlike traditional logins, these credentials are stored in your crypto wallet and can be used across multiple applications without relying on a central authority. The core prerequisites are a Web3 wallet, a small amount of cryptocurrency for transaction fees, and developer accounts with the verification services you plan to integrate. This setup enables applications to verify users based on their on-chain activity, social graph, or real-world identity proofs.

Your primary tool is a non-custodial wallet like MetaMask, WalletConnect, or Rainbow. This wallet holds your private keys and will store your verifiable credentials. You will need to fund it with a small amount of native cryptocurrency for the network you're using (e.g., ETH for Ethereum, MATIC for Polygon) to pay for transaction fees, known as gas. For testing, you can use a testnet like Sepolia or Mumbai to avoid spending real funds. Most verification protocols operate on Layer 2 networks like Polygon for lower costs.

Next, you'll need to create developer accounts with the credential providers. For World ID, sign up at the World ID Developer Portal to get an app ID and integrate the widget or SDK. For Gitcoin Passport, register at the Gitcoin Passport app to start accumulating stamps from services like BrightID, ENS, and POAP. For Lens Protocol, you'll need a Lens Profile NFT, which may require an invitation or minting on testnet, and you should explore the Lens API documentation.

From a development perspective, you'll need a code environment. A Node.js project (version 16 or later) is standard. Install necessary SDKs via npm or yarn, such as @worldcoin/idkit for World ID, @gitcoin/passport-sdk-types for Passport, or @lens-protocol/client for Lens. You will also need a basic understanding of how to interact with a wallet from a frontend using libraries like ethers.js or viem. Setting up a simple Next.js or Vite application is a common starting point for integration.

Finally, plan your verification logic. Determine what credential or combination of stamps constitutes a valid verification for your application. For example, you might require a World ID orb verification for uniqueness, a Gitcoin Passport score above 20, or a Lens profile with a minimum follower count. Your smart contract or backend service will need to verify these credentials on-chain using the protocol's verifier contracts or off-chain via their APIs. Start by testing the flow end-to-end on a testnet before deploying to production.

Decentralized social credential verification is built on three core standards: Decentralized Identifiers (DIDs), Verifiable Credentials (VCs), and on-chain attestations. A DID is a unique, self-owned identifier, such as did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK, that is not controlled by a central registry. It serves as the root for a user's digital identity, allowing them to receive and present credentials without relying on a traditional username/password system from a single provider like Google or Facebook. This shifts control from centralized platforms to the individual.

Verifiable Credentials (VCs) are the digital, cryptographically signed equivalent of physical credentials like a driver's license or university degree. A VC is a JSON-LD or JWT document containing claims (e.g., "Alice has a GitHub account") issued by an issuer (like GitHub) to a holder (Alice's DID). The signature, typically using Ed25519 or secp256k1, proves the issuer created it and the data hasn't been tampered with. The holder stores their VCs in a digital wallet (e.g., MetaMask Snap, Spruce ID) and can choose which credentials to share, enabling selective disclosure of information.

Social proof in this context refers to verifiable evidence of reputation or activity, often recorded on-chain. While a VC can attest to a static fact ("has 10K Twitter followers"), on-chain social proof is dynamic and publicly verifiable. Protocols like Ethereum Attestation Service (EAS) or Gitcoin Passport allow entities to issue attestations—cryptographic stamps—directly to an Ethereum address or DID. For example, a DAO could issue an attestation proving a user completed a governance proposal, creating a permanent, portable record of contribution that can be queried by any dApp.

The verification flow involves several steps. First, a user authenticates with their DID, often via Sign-In with Ethereum (SIWE). A verifier's dApp then requests specific credentials, such as a proof of humanity from Worldcoin or a GitHub contribution history VC. The user's wallet presents the VC, and the verifier checks the cryptographic signature against the issuer's public DID and ensures the credential hasn't been revoked (e.g., by checking a revocation list or a smart contract registry). This creates a trust model based on cryptography and open standards, not corporate gatekeeping.

For developers, implementing this stack requires integrating libraries like Spruce ID's didkit, veramo, or EAS SDK. A basic flow involves generating a DID, requesting a VC from an issuer API, and presenting it. Code to verify a JWT VC with veramo might look like:

javascriptCopy
const result = await agent.verifyCredential({
  credential: jwtCredential,
});
if (result.verified) { /* Grant access */ }

Frameworks like Disco and Coinbase's Verifier provide tooling to simplify issuing and verifying credentials for common social platforms.

The ultimate goal is interoperable reputation. A user's GitHub VC, DAO contribution attestation on Optimism, and POAP from a conference can be composed into a rich, user-controlled identity graph. This portable social proof can unlock gated experiences—from token-gated Discord servers to sybil-resistant airdrops and undercollateralized lending—without surrendering personal data to each new platform. The shift from centralized profiles to user-held, cryptographically verifiable credentials represents a fundamental re-architecture of online identity and trust.

The Lens Protocol provides a foundational layer for decentralized social applications by storing user profiles, connections, and content as non-fungible tokens (NFTs) on the Polygon blockchain. A user's profile is an ERC-721 NFT that acts as their on-chain identity. This profile NFT can collect follow NFTs from other users, mint publication NFTs for posts and comments, and be managed via a flexible module system. This architecture shifts social data ownership from centralized platforms to individual users, enabling portable reputation and composable social features across any dApp built on Lens.

To begin integration, developers must first interact with the core LensHub contract. The primary entry point is the LensHub smart contract deployed on Polygon Mainnet at 0xDb46d1Dc155634FbC732f92E853b10B288AD5a1d. You will need to use the Lens API (https://api.lens.dev) for efficient data queries and the Lens SDK (via @lens-protocol/client) for easier client-side interactions. The SDK abstracts much of the blockchain complexity, providing methods for authentication, profile management, and publication handling. For direct contract calls, the ABI is available on the Lens Protocol GitHub repository.

The first actionable step is to authenticate a user and fetch their profile. Using the Lens Client SDK, you initialize a client bound to the Polygon network. User authentication is handled via SIWE (Sign-In with Ethereum), which generates a challenge that must be signed by the user's wallet. Upon successful authentication, you can query the user's owned profile NFTs. A key concept is the profile ID, a unique integer (e.g., 0x01) that identifies a Lens profile. All subsequent interactions—such as checking follows, fetching publications, or posting content—are scoped to this profile ID.

A core feature for credential verification is checking a user's social graph state. You can verify if a user follows a specific profile or collects their publications by querying the isFollowing or isCollected methods on the hub contract. For example, a governance dApp might require that a user follows an official project channel (profileId: 0x1234) to be eligible to vote. This check is a simple, on-chain verification of a social relationship, leveraging the graph's immutable and permissionless nature. These relationships are stored as Follow NFTs issued to the follower, providing cryptographic proof.

For advanced logic, Lens uses a module system. Developers can write custom Follow Modules, Reference Modules, and Collect Modules that govern the rules for social interactions. A follow module could, for instance, implement a token-gated follow, where users must hold a specific ERC-20 token to follow a profile. These modules are attached to profiles or publications and execute automatically when users interact with them. This extensibility is what makes Lens a composable social graph, allowing developers to build unique social mechanics and verification rules directly into the protocol layer.

Finally, always reference the official Lens Documentation for the latest contract addresses, API endpoints, and SDK methods. The ecosystem evolves rapidly, with new modules and best practices emerging. When implementing, consider gas costs on Polygon, the user experience of wallet signing, and the indexing delay (typically a few blocks) for on-chain actions to be reflected in the API. Proper integration establishes a robust foundation for building applications that leverage verifiable, user-owned social data.

A verifiable credential is a tamper-proof digital attestation, like a diploma or proof-of-personhood, that an issuer signs and a holder stores. The Disco Data Backpack acts as a user-centric credential wallet, allowing you to issue VCs to Ethereum addresses. To begin, you'll need to set up the Disco API. First, create an account on the Disco developer portal and generate an API key. This key authenticates your requests to the Disco backend, which handles the cryptographic signing and on-chain anchoring of credentials using the Ethereum Attestation Service (EAS).

The core of issuing a credential is constructing a valid payload. A VC follows the W3C Verifiable Credentials Data Model and includes essential fields: an issuer (your Disco DID), a credentialSubject (the recipient's DID or Ethereum address), and the specific claims or attributes being attested. For a social credential, claims might include platform, username, and verificationDate. You must also specify a type, such as "SocialProof", and an expiration date to ensure credentials remain current.

Here is a basic example of a credential issuance request using the Disco API with curl. Replace YOUR_API_KEY, the recipient's address, and other fields with your data.

bashCopy
curl -X POST https://api.disco.xyz/v1/credential/ \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "issuer": "did:disco:your-issuer-id",
    "schema": "https://schemas.disco.xyz/social-proof",
    "credentialSubject": {
      "id": "did:pkh:eip155:1:0xRecipientAddress",
      "platform": "Farcaster",
      "username": "alice",
      "verifiedSince": "2024-01-15"
    },
    "expirationDate": "2025-12-31T23:59:59Z"
  }'

A successful request returns a credential id and a status URL to track issuance.

After issuance, the credential is cryptographically signed by your Disco issuer key. Disco then creates an on-chain attestation via EAS on Optimism or Ethereum mainnet, providing a public, immutable proof of issuance. The credential is simultaneously sent to the recipient's Data Backpack. The holder can now present this VC to verifiers (like dApps or other protocols) to prove their social identity or membership without revealing unnecessary personal data, enabling selective disclosure.

For developers, managing issuance at scale is crucial. The Disco API supports batch operations and webhooks for event notifications (e.g., credential.issued). You should implement robust error handling for cases like invalid recipient addresses or exceeded rate limits. Always store credential IDs from the API response in your application's database to maintain an audit trail. For production systems, consider using credential revocation lists or time-based expirations to manage the credential lifecycle and maintain system integrity.

This capability forms the foundation for decentralized social graphs and trust networks. By issuing VCs, you enable users to port their reputation across applications—imagine using a Farcaster follower proof to access a gated Discord or a DAO. The next step is to build a verifier that can check these credentials, completing the cycle of trust in a user-owned identity stack.

CyberConnect is a decentralized social graph protocol that allows developers to build applications where users own their social connections. Unlike traditional social networks where your follower list is locked into a single platform, CyberConnect stores these connections on the blockchain. This creates a portable, user-centric social identity that can be used across multiple dApps, from Web3 social platforms to credentialing services and DAO tools. The protocol aggregates connections by recording follow, like, and other social actions as verifiable on-chain attestations.

To integrate CyberConnect, you'll typically interact with its smart contracts on supported networks like Ethereum, Polygon, or Base. The core action is writing a connection to the graph, which is a permissionless transaction. For example, when a user follows another address, your dApp calls the connect function on the CyberConnect contract. This mints a Follow NFT to the follower, serving as a verifiable, non-transferable record of that connection. These NFTs are stored in the user's wallet, giving them full ownership and control over their social graph data.

Here's a basic JavaScript example using the CyberConnect SDK to initialize a connection and follow a user:

javascriptCopy
import CyberConnect from '@cyberlab/cyberconnect-js';

const cyberConnect = new CyberConnect({
  provider: window.ethereum, // User's wallet provider
  namespace: 'YourAppName'
});

// Address to follow
const addressToFollow = '0x1234...';

// Execute the follow
await cyberConnect.connect(addressToFollow);

This code prompts the user to sign a transaction, which then records the follow relationship on-chain. The namespace parameter allows your application to create its own isolated social graph within the protocol.

Verifying these aggregated connections is straightforward for other applications. By querying the CyberConnect subgraph on The Graph protocol, any service can check a user's social footprint. You can fetch all addresses a user follows, their followers, or even the aggregate connection strength between two profiles. This enables use cases like social recovery for wallets, where trusted connections can help regain access, or sybil resistance, where genuine user activity is distinguished from bot farms based on their established social graph.

When designing your implementation, consider key protocol limits and costs. As of early 2024, connection actions require a small gas fee on the underlying blockchain. The protocol also imposes rate limits to prevent spam. For production applications, you should implement client-side caching of graph data to reduce RPC calls and provide a smoother user experience. Always refer to the latest CyberConnect documentation for contract addresses, SDK updates, and network support.

The verification logic is the heart of your decentralized credential system. It's a smart contract that receives attestations from your off-chain indexer, validates them against predefined rules, and issues a verifiable credential—often as an SBT (Soulbound Token) or a standard ERC-721—to the user's wallet. The contract must be gas-efficient, secure, and capable of handling state updates from a trusted oracle or relayer. Key functions include verifyAndMint, revokeCredential, and checkValidity.

Start by defining the credential's data structure. This typically includes the issuer's address, the recipient's address, a unique credential ID, the attestation timestamp, an expiration block (if applicable), and a cryptographic proof or signature. Use a mapping to store credentials by user address for efficient lookup. For example:

solidityCopy
struct SocialCredential {
    address issuer;
    uint256 issuedAt;
    uint256 expiresAt;
    bytes32 proofHash;
}
mapping(address => SocialCredential) public credentials;

The verifyAndMint function is the most critical. It should be callable only by a designated verifier address (your indexer's wallet or a multisig). It must verify the off-chain attestation's signature, check that the user doesn't already hold a valid credential, and enforce any business logic (e.g., minimum follower count). Upon successful verification, it mints the token and stores the credential data. Always include event emissions (e.g., CredentialIssued) for off-chain tracking.

Consider upgradeability and security from the start. Use established patterns like the Transparent Proxy or UUPS to allow for future logic fixes without losing state. Implement a pause mechanism and role-based access control (using OpenZeppelin's AccessControl). Crucially, the logic for validating the off-chain proof must be robust; a common method is to have the indexer sign a structured message (EIP-712) containing the credential details, which the contract then verifies using ECDSA.recover.

Finally, thoroughly test your contract. Write unit tests for all functions and edge cases: double-minting, expired credentials, signature replay attacks, and calls from unauthorized addresses. Use a forked mainnet environment (with Foundry or Hardhat) to simulate real gas costs and interactions with live protocols like ENS or Lens Protocol. Deploy first to a testnet (Sepolia, Holesky) and verify the source code on block explorers like Etherscan before considering a mainnet launch.

This guide walked you through the core components: using the Ethereum Attestation Service (EAS) to create and verify on-chain attestations, leveraging Sign-In with Ethereum (SIWE) for secure wallet-based authentication, and integrating with Ceramic Network for storing portable, user-owned social data. The result is a system where a user's social reputation—like a verified Twitter following or GitHub contribution history—can be cryptographically proven and referenced across applications without relying on a central database.

For production deployment, several critical steps remain. First, implement robust revocation logic. EAS supports both on-chain and off-chain revocation, so your application's frontend and smart contracts must check the revoked status of an attestation UID before accepting it. Second, design your schema carefully. The schema you register on EAS defines the immutable structure of your attestations. Consider future needs for fields like expiryTimestamp or linking to parent attestations for building credential graphs. Third, manage gas costs and scalability. Batching attestations or using a gas-efficient L2 like Optimism or Base for the EAS registry can significantly reduce operational expenses.

To extend this system, explore composability with other identity primitives. You could use the verified credential as a gate for a Sybil-resistant airdrop or as a requirement in a DAO governance contract. The attestation UID can be used as a key in Lens Protocol or Farcaster to link social actions to a verified identity. Furthermore, consider adopting the Verifiable Credentials (W3C VC) data model for even broader interoperability with the decentralized identity ecosystem.

The code examples provided are a starting point. You should add comprehensive error handling, event listening for real-time updates, and frontend state management to reflect the status of pending and confirmed attestations. Always audit your smart contract interactions and consider using a library like Ethers.js or Viem for type-safe contract calls. For continued learning, review the official EAS Documentation and explore the Ceramic ComposeDB for more advanced data modeling capabilities.