Koru:
On-Chain NFT Evolution
A complete end-to-end Solana NFT ecosystem featuring fair reveals, non-custodial staking with flexible lock periods, and deflationary burn mechanics.
Project Overview
Koru was a comprehensive NFT collection project built for a client on the Solana blockchain. It required building multiple interconnected systems that pushed the boundaries of what's possible with the Metaplex Core standard.
The ecosystem centered around three pillars: an On-Chain Reveal System for fair trait distribution, a Non-Custodial Staking Platform allowing users to earn rewards without losing ownership, and Deflationary Burn Mechanics for both NFTs and tokens.
Built entirely by a single developer, this project demonstrates expertise in Rust smart contract development (Anchor), React/TypeScript frontend engineering, and deep Solana blockchain integration.
Technical Stack
Solana Programs (Rust)
Frontend (React/TS)
Technical Implementation
Detailed breakdown of the core logic and architecture used in the Koru ecosystem.
On-Chain Reveal & Bitmap Logic
Challenge
Implementing a fair, transparent reveal system that prevents manipulation while being gas-efficient on-chain.
Technical Solution
Developed a vault-based storage approach using a bitmap system to track revealed NFTs. The logic uses block timestamps combined with revealed counts for pseudo-random selection, with collision detection to ensure every NFT is unique.
Key Logic Highlights
Uses 0.005 SOL + 35,000 KORU token burn per reveal
Direct CPI updates to Metaplex Core asset metadata
Efficient bitmap tracking to prevent duplicate reveals
Vault storage for massive metadata handling
Non-Custodial Staking with MPL Core
Challenge
Allowing users to stake NFTs for rewards while maintaining asset ownership in their own wallets.
Technical Solution
Leveraged Metaplex Core's freeze plugin. The program acts as a freeze delegate, locking the NFT on-chain while the user remains the owner. This bypasses the need for risky custodial vaults.
Key Logic Highlights
Flexible lock periods: 1 week (1x) to 1 year (12x)
Automatic rarity tracking for multiplier calculation
Early unstake penalty mechanism with KORU burn
Program-derived addresses (PDAs) for secure state management
Smart Contract Architecture
Exploring the core Rust implementation for the reveal and staking programs.
pub fn reveal(ctx: Context<RevealCtx>) -> Result<()> {
let reveal = &mut ctx.accounts.reveal_state;
let clock = Clock::get()?;
// --- 1. Charge User (0.005 SOL + Token Burn) ---
let lamports = 5_000_000;
system_program::transfer(CpiContext::new(...), lamports)?;
let burn_amount = 35_000 * 10u64.pow(decimals);
token::burn(CpiContext::new(...), burn_amount)?;
// --- 2. Reveal Logic (Randomization & Collision Check) ---
let mut idx = ((clock.unix_timestamp as u32)
.wrapping_add(reveal.revealed_count)) % reveal.total_count;
while reveal.is_revealed(idx) {
idx = (idx + 1) % reveal.total_count;
}
// --- 3. Update MPL Core Asset ---
UpdateV1CpiBuilder::new(&ctx.accounts.mpl_core_program)
.asset(&ctx.accounts.asset)
.new_name(format!("{}{}", prefix, name))
.new_uri(format!("{}{}", prefix, uri))
.invoke_signed(signers_seeds)?;
reveal.set_revealed(idx)?;
Ok(())
}Web3 Frontend Integration
The frontend was built with React and TypeScript, integrating seamlessly with the Solana blockchain using `@solana/web3.js` and `@coral-xyz/anchor`.
Clean separation of concerns with a dedicated Web3 layer for transaction building and error handling.
Real-time feedback for blockchain transactions using custom Framer Motion animations and modal systems.
// Frontend Reveal Implementation
export const reveal = async (program, wallet, nft) => {
const revealState = (await program.account.reveal.all())[0];
const userTokenAccount = await getAssociatedTokenAddress(
KORU_MINT,
wallet.publicKey
);
return await program.methods
.reveal()
.accounts({
recipient: RECIPIENT_PUBKEY,
revealState: revealState.publicKey,
revealVault: revealState.account.revealVault,
tokenMint: KORU_MINT,
userTokenAccount,
asset: nft.publicKey,
collection: COLLECTION_PUBKEY,
})
.rpc();
};100%
Collection Minted
Successful
Brand Merger
Production
Ready Security