Senior Blockchain Engineer - Web3 & Smart Contracts

SIDRAM TECHNOLOGIES; New York (NY); On-site; USD 170,000 - 260,000; Full time

Job summary

Citi Bank is seeking an experienced Blockchain Developer to design, develop, and deploy Web3 components for its Digital Asset Platform. You will work on smart contracts, wallet solutions, and cross-network integrations, collaborating with global engineering teams.

Ideal candidates bring 10+ years in blockchain, strong security focus, and hands-on experience with Ethereum ecosystems, token standards, and DevOps practices to deliver scalable, compliant infrastructure.

Qualifications

• 10+ years of experience in Blockchain/Web3 development.
• Experience designing, developing and deploying smart contracts and backend integrations for digital asset platforms.
• Strong knowledge of Ethereum-compatible networks, and token standards (ERC-20/721/1155).
• Familiarity with security best practices and smart contract audit concepts.

Responsibilities

• Build and integrate Web3 components, smart contracts and blockchain protocols.
• Develop backend services connecting to public and permissioned blockchain networks.
• Build, test and audit secure and gas-efficient smart contracts.
• Implement event-driven architectures for on-chain events and lifecycle management.
• Support digital asset custody, tokenization and DeFi/TradFi integrations.
• Collaborate with architects and senior engineers on scalable Web3 infrastructure.
• Participate in code reviews, testing, documentation and Agile/Scrum delivery.

Skills

Blockchain / Web3 Development

Solidity Smart Contracts

Java / Spring or Node.js

Web3J / Web3JS / Ethers.js / Viem

Smart Contract Testing

ERC-20 / ERC-721 / ERC-1155 / ERC-3525

Event-Driven Architecture

Kafka / RabbitMQ

Docker / Kubernetes / CI/CD

Cryptography / PKI & Key Management

Git / Jira / Jenkins / Helm

Tools

Web3J / Web3JS / Ethers.js / Viem

Docker

Kubernetes

CI/CD

Git

Jira

Jenkins

Helm

Job description

Citi Bank is seeking an experienced Blockchain Developer to design, develop, and deploy Web3 components for its Digital Asset Platform. You will work on smart contracts, wallet solutions, and cross-network integrations, collaborating with global engineering teams.

Ideal candidates bring 10+ years in blockchain, strong security focus, and hands-on experience with Ethereum ecosystems, token standards, and DevOps practices to deliver scalable, compliant infrastructure.