Completed
ZKPass
A gasless, on-chain access control system using Merkle Trees to verify allowlist eligibility and mint access passes without user gas fees.
Overview
ZKPass is a hybrid on-chain/off-chain access management platform. It allows admins to create campaign allowlists via Merkle Roots while enabling users to claim passes gaslessly through a backend relayer. By moving proof generation off-chain and verification on-chain, ZKPass achieves a high-performance, cost-effective solution for private community gating and allowlist-only mints.
What Users Can Do
- Create and deploy allowlist-gated campaigns by uploading wallet lists.
- Generate secure Merkle proofs off-chain to verify eligibility.
- Claim access passes with zero gas fees via a backend-sponsored relayer.
- Check real-time eligibility status for active campaigns.
- Track claim history and on-chain pass ownership through a unified dashboard.
- Experience seamless onboarding without needing initial ETH for gas.
Why I built this
- To implement Merkle Trees as a core infrastructure primitive for scalable on-chain verification.
- To build a secure backend relayer capable of sponsoring and submitting transactions on behalf of users.
- To explore hybrid architecture—balancing blockchain finality with Postgres-backed state tracking.
- To solve the 'cold start' problem in Web3 where users need ETH just to interact with a dApp.
- To reach the halfway mark of the '6 Projects in 60 Days' challenge with a complex cryptography project.
Tech Stack
Solidity
Next.js
Nest.js
TypeScript
PostgreSQL
Prisma
Viem
Wagmi
Turborepo
After launch & Impact
- Successfully deployed a gasless UX that abstracts away the complexity of transaction fees for the end user.
- Designed an idempotent claim tracking system to prevent double-claiming across DB and Chain state.
- Optimized proof generation performance by handling Merkle Tree computations in the NestJS backend.
- Implemented a secure relayer wallet management system with automated noncing and submission logic.
- Mastered the deployment of dynamic, per-campaign smart contracts via a central factory-style pattern.
Future Plans
- Migrate the relayer to a full ERC-4337 Paymaster variant for native gas sponsorship.
- Integrate IPFS for decentralized storage of Merkle Trees and campaign metadata.
- Add support for time-limited and supply-capped access pass campaigns.
- Build a comprehensive analytics dashboard for admins to track claim rates and user demographics.
- Implement Subgraph integration to index on-chain minting events for decentralized reporting.