Backend Java Developer – Data Fabric / Platform Engineering

NextWave Consulting Ltd; City Of London; Hybrid; GBP 70,000 - 90,000; Full time

Job summary

A leading consultancy firm is looking for a Backend Java Developer for a hybrid role in London. You will build core backend services for a Data Fabric platform, implementing rule engines and working with SQL parsing and distributed data systems. Ideal candidates should have strong experience in Java (17/21), Spring, and a solid understanding of SQL optimization. This position offers a competitive salary ranging from £70,000 to £90,000 based on experience, and focuses on deep backend development.

Qualifications

• Strong hands-on experience with Java (17/21) and Spring.
• Deep understanding of JDBC, SQL parsing, and query planning.
• Experience with production-grade testing using JUnit 5 and Mockito.

Responsibilities

• Build core backend services for access control and query manipulation.
• Implement deterministic policy/rule engines for data governance.
• Integrate with distributed data platforms and query engines.

Skills

Java (17/21)

Spring

SQL parsing/validation

CI/CD

Docker

JUnit 5

Mockito

query planning/optimization

Tools

Docker

Maven

Jenkins

Job description

Backend Java Developer – Data Fabric / Platform Engineering

Location: London (Hybrid)
Employment: Permanent
Salary: £70,000 – £90,000 base (dependent on experience)

If your idea of backend engineering is more than CRUD APIs and microservices boilerplate — this role is for you.

We’re building the core backend services of a Data Fabric platform that governs data access, entitlements, and query policy enforcement across distributed enterprise data systems.
This is platform engineering: deterministic rule engines, SQL planning/interception, and high-throughput services that sit on the critical path of data access.

This is deep backend + data infrastructure work.

🚀 What You’ll Do

• Build core backend services in Java (17/21) for access control and query manipulation
• Implement deterministic policy / rule engines for data governance
• Work on SQL parsing, planning, validation, and transformation (e.g., Calcite or similar planners)
• Integrate with distributed data platforms / query engines (e.g., Starburst or similar)
• Own API contracts with living documentation in CI/CD
• Build production-grade, testable pipelines
• Drive observability, reliability, and performance
• Contribute to architecture decisions (modularity, DI, extensibility)

What You Bring (Must-Have)

• Strong hands-on experience in Java (17/21) + Spring
• Deep understanding of JDBC, SQL parsing/validation, query planning/optimization
• Experience with SQL planners or query transformation layers
• Strong grounding in data structures, algorithms, and backend performance
• Production-grade testing using JUnit 5, Mockito
• Experience with clean architecture, DI, modular design
• Comfortable owning CI/CD, code quality, observability
• Familiarity with Docker, Maven, Jenkins

⭐ Nice to Have

• Apache Calcite
• Starburst or federated query engines
• JVM performance tuning
• High-throughput service interfaces (REST/gRPC)
• Data governance or policy enforcement layers

👥 This Role Is Ideal If You’ve Worked On

• Data platforms, governance layers, query engines, or SQL planners
• Backend/platform services that sit in the critical path of data access
• Systems where correctness, determinism, and performance matter