Blockchain Java Backend Engineer

Job DescriptionMust Have Technical/Functional SkillsCore Backend Skills Strong proficiency in Java (8+), and frameworks such as Spring Boot / Spring Cloud. Experience building distributed systems and microservices architectures at scale. Strong knowledge of:Concurrency, multithreading, asynchronous programmingAPI design (REST/gRPC), security (OAuth2/JWT), and integration patterns Solid understanding of data stores:SQL (PostgreSQL/MySQL) and/or NoSQL (MongoDB/Cassandra)Caching (Redis) and search (Elasticsearch) is a plus Hands-on experience with message streaming/queues:Blockchain Skills (Must-Have) Strong understanding of blockchain fundamentals:Transactions, blocks, confirmations/finality, consensus, gas/fees, wallets, keys. Experience integrating backend services with blockchain networks/nodes:Ethereum-compatible networks (Ethereum/Polygon/BSC) using Web3j, ethers-style approachesand/or permissioned chains (Hyperledger Fabric, Corda, Quorum) Experience supporting large blockchain deployments:Node connectivity, RPC management, event indexing, chain reorg handling, retry strategies.________________________________________DevOps / Cloud (Preferred) Experience with Docker and Kubernetes for containerized microservices deployments. CI/CD exposure (Jenkins/GitHub Actions/GitLab CI/Azure DevOps). Cloud experience (Azure/AWS/GCP) is a plus. Understanding of security practices:Secrets management (Vault/KMS), TLS, RBAC, network security.Roles & Responsibilities Design and develop Java-based backend services that interact with blockchain networks and nodes (public or permissioned). Build and scale microservices-based architecture supporting blockchain transaction workflows, event processing, and off-chain components. Develop reliable services for:Transaction orchestrationSmart contract invocationBlockchain event subscription/listeningOn-chain/off-chain data synchronization Implement scalable APIs (REST/gRPC) for blockchain-enabled products and integrations. Optimize performance for high throughput and low latency:Transaction throughput handling, batching, retries, idempotency, rate limiting. Ensure secure integration with blockchain:Key management best practices, signing transactions, secure secret handling. Implement observability and reliability standards:Logging, monitoring, tracing, alerting, SLOs/SLAs. Work with DevOps/SRE teams to support production deployments, incident triage, and capacity planning. Contribute to architecture decisions including:Event-driven architecture (Kafka/RabbitMQ), caching strategies, database selection, and deployment topologies.Salary Range: $100,000 to $130,000 per yearQualifications: BACHELOR OF COMPUTER SCIENCE