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