Blockchain Developer - Citi Bank

SIDRAM TECHNOLOGIES; United States; On-site; USD 140,000 - 220,000; Full time

Job summary

SIDRAM TECHNOLOGIES is seeking an experienced Blockchain Developer to design, develop, and deploy Web3 components for Citi Bank’s Digital Asset Platform. You will work on smart contracts, backend integrations, wallet solutions and asset infrastructure from New York/ Jersey City.

Ideal candidates have 10+ years in development, strong security mindset, and a track record delivering scalable blockchain solutions with Java/Node.js, Ethereum or Hyperledger Besu, and modern devops tooling.

Qualifications

• 10+ years in software development with a blockchain focus.
• Experience designing and deploying Web3 components for enterprise platforms.
• Strong knowledge of smart contract security and auditing practices.

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 transaction lifecycle management.
• Support digital asset custody, tokenization and DeFi/TradFi integrations.
• Collaborate with architects and senior engineers on scalable and secure Web3 infrastructure.
• Participate in code reviews, testing, documentation and Agile/Scrum delivery.

Skills

Blockchain / Web3 Development

Solidity Smart Contracts

Ethereum / Hyperledger Besu / Corda

Java / Spring or Node.js

Web3J / Web3JS / Ethers.js

Smart Contract Testing

Blockchain Fundamentals

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

Event-Driven Architecture

Kafka / RabbitMQ

Docker / Kubernetes / CI/CD

Cryptography / PKI

Git / Jira / Jenkins / Helm

Education

Bachelor’s degree in Computer Science or related field

Tools

Docker

Kubernetes

CI/CD

Job description

NOW HIRING: BLOCKCHAIN DEVELOPER CITI BANK

Client: Citi Bank

Location: New York, NY / Jersey City, NJ

Position Type: Full-Time

Experience: 10+ Years

Role Overview

Seeking an experienced Blockchain Developer to design, develop, and deploy Web3 components and integrations for Citi's Digital Asset Platform, including smart contracts, blockchain integrations, wallet solutions, and digital asset infrastructure.

Must-have Skills

• Blockchain / Web3 Development
• Solidity Smart Contracts
• Ethereum / Hyperledger Besu / Corda or equivalent
• Java / Spring or Node.js
• Web3J / Web3JS / Ethers.js / Viem
• Smart Contract Testing: Hardhat / Foundry / Truffle
• Blockchain Fundamentals Consensus, Transactions, Gas & Wallet Infrastructure
• ERC-20 / ERC-721 / ERC-1155 / ERC-3525
• Event-Driven Architecture / Asynchronous Programming
• Kafka / RabbitMQ
• Docker / Kubernetes / CI/CD
• Cryptography Digital Signatures, Hashing, PKI & Key Management
• Git / Jira / Jenkins / Helm

Preferred / Plus Skills

• Hyperledger Besu / Fabric / Corda / R3
• Layer 2 Polygon / Optimism / zkSync
• Cross-Chain Interoperability
• Digital Asset Custody
• Tokenization / DeFi / TradFi
• Financial Services / Regulated Industry Experience
• Agile / Scrum

Key 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 transaction lifecycle management.
• Support digital asset custody, tokenization and DeFi/TradFi integrations.
• Collaborate with architects and senior engineers on scalable and secure Web3 infrastructure.
• Participate in code reviews, testing, documentation and Agile/Scrum delivery.

IDEAL CANDIDATE

• Strong Web3 engineering and backend development background.
• Strong security mindset and knowledge of smart contract vulnerabilities.
• Excellent problem-solving and communication skills.
• Strong understanding of APIs, microservices, data structures and design patterns.
• Ability to work effectively with global, distributed engineering teams.