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Fiverr Pro
English
$
USD
I will build a secure web3 backend with fastapi or nodejs
Web3 Dapps, Smart Contract, Solidity, Nodejs, Python
I am a Web3 and software developer specializing in production-ready smart contracts and full-stack decentralized applications. I build secure Solidity contracts, automated trading bots, and scalable b...
Level 1
Has met certain performance criteria and shows strong potential in the marketplace.
About this Gig
Most Web3 projects fail because the backend is unreliable, insecure, or cannot track blockchain payments correctly.
If your project needs a backend that actually works on-chain one that handles wallet authentication, listens to blockchain events, confirms payments, and scales under load you're in the right place.
I build production-ready Web3 backends using FastAPI, Node.js, Web3.py, and Ethers.js, with a hard focus on security, scalability, and correctness.
What I Build
You're not buying a generic 'backend.' You're buying business logic that touches the blockchain the part most developers get wrong.
- Wallet Authentication SIWE (Sign-In with Ethereum), MetaMask integration
- Blockchain Event Listener ETH, ERC20, real-time on-chain tracking
- Payment Confirmation System reliable, idempotent, production-safe
- Web3 REST API FastAPI or Express, clean endpoints, documented
- Database Integration Postgres, MongoDB, optimized schemas
- Background Workers async tasks, cron jobs, message queues
- RPC + WSS Integration Infura, Alchemy, self-hosted nodes
- Secure Admin Panel Logic role-based access, audit trails
Keep your assets and information safe
Cryptocurrency services focus solely on developing and programming. Never share sensitive information or private keys with others.
My Portfolio
Other Blockchain Development & Solutions Services I Offer
FAQ
Can you work with my existing codebase?
Yes. Share your repo details in the project brief and I'll review before we start.
Which blockchains do you support?
Ethereum and EVM-compatible chains (Polygon, BNB, Base, Arbitrum). Multi-chain is available in the Premium package.
Do you handle deployment?
Deployment guidance is included in the Premium and Standard package . For Basic, I deliver fully working code with Docker-ready configuration.
What if I need something custom?
Message me before ordering. I handle custom scopes and can provide a tailored quote.
