⚡ VRFChain — Blockchain with Verifiable Random Function (VRF)

VRFChain is a custom blockchain built using Ignite CLI that implements Verifiable Random Functions (VRFs) — cryptographic primitives that generate provably fair and verifiable random numbers on-chain.

This chain allows anyone to create, store, and verify randomness in a decentralized manner — enabling use cases like lotteries, gaming, fair leader election, and secure random selection.

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🚀 Features

• ✅ Generate On-Chain Random Numbers using verifiable randomness

• 🔐 Verify Random Outputs with public-key cryptography

• ⚙️ Cosmos SDK + Ignite CLI powered blockchain module

• 📡 Simple REST Endpoints:

  • POST /CreateVerifiableRandomNumber — Create random number request
  • GET /VerifyNumber — Verify generated number against proof

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🧠 How It Works

1. User submits input (shaSeed, publicKey, r, s, maxRange) to generate a verifiable random number.
2. The chain module computes the random number using VRF cryptography.
3. A proof is attached that allows anyone to verify the randomness.
4. Using GET /VerifyNumber, users can validate that the number was truly random and not tampered with.

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🏗️ Scaffold Commands Used

This chain was initialized with the following Ignite commands:

ignite scaffold module vrf
ignite scaffold message create-verifiable-random-number shaseed publickey r s max-range --module vrf

These commands create the vrf module and the message handler for verifiable randomness generation.

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💻 Run the Blockchain

To start the local blockchain node:

ignite chain serve

This command:

• Builds and serves the blockchain locally
• Starts REST and gRPC servers for module interaction
• Automatically generates the client, daemon, and configuration files

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🔍 API Endpoints

Method	Endpoint	Description
POST	/CreateVerifiableRandomNumber	Create and broadcast a VRF-based random number transaction
GET	/VerifyNumber	Verify a previously generated number and proof

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🧩 Example Use Cases

• 🎰 Decentralized lotteries and on-chain games
• 🗳️ Random validator selection
• 🎲 Fair random draws in DAOs
• 🔄 Randomized asset distribution in NFTs

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⚙️ Tech Stack

Component	Technology
Framework	Ignite CLI
Blockchain SDK	Cosmos SDK
Language	Go (Golang)
Module	Custom vrf Cosmos module
Cryptography	Verifiable Random Function (VRF)

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📦 Project Structure

vrfchain/
 ├── x/vrf/                # VRF module logic
 │   ├── keeper/           # State management and verification
 │   ├── types/            # Message and type definitions
 │   └── module.go         # Cosmos SDK module entry point
 ├── app/                  # Chain initialization and configuration
 ├── cmd/                  # CLI entry points
 ├── config.yml            # Ignite configuration
 └── README.md

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🧪 Testing Locally

To test transactions:

# Create random number
ignite tx vrf create-verifiable-random-number <shaSeed> <publicKey> <r> <s> <maxRange> --from <key>

# Verify result
ignite query vrf verify-number <number-id>

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🧠 Future Improvements

• 🔄 Add on-chain proof verification logic
• 🧮 Integrate BLS or Ed25519-based VRF
• 🌐 Add front-end dashboard for randomness requests
• ☁️ Enable Tendermint RPC interaction

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📜 License

This project is licensed under the MIT License.

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👨‍💻 Author

Aakash 🌐 aakash4dev.com X (Twitter) • LinkedIn • Medium