Senior Software Engineer

Sellick Partnership; Bath; Hybrid; GBP 70,000 - 110,000; Full time

Benefits offered by this job

Enhanced family leave

Life assurance

Company social events

25 days annual leave

Job summary

Sellick Partnership seeks a Senior Software Engineer for a UK defence programme based in Bath with hybrid working (approximately 3 days on-site). You will own backend design and integrations across ERP systems, data platforms and external tech, delivering production-ready solutions in a complex, multi-year project.

You will work primarily with Java and SQL, build REST and event-driven interfaces, and shape architecture, security and performance. SC eligibility is required for this role.

Qualifications

• Experience with backend design and APIs in Java or equivalent
• Strong SQL and data integration skills required
• Experience building/connecting ERP data platforms and data lakes/lakehouses
• Familiarity with REST and event-driven architectures; CDC is valuable
• Experience in CI/CD, automated testing and observability
• Ability to design scalable, secure, high-availability systems
• UK nationals eligible for SC clearance; defence programme experience a plus

Responsibilities

• Design and build backend services and APIs.
• Develop integrations with ERP systems, data platforms and external technologies.
• Work across Java, SQL and data/integration tooling.
• Design REST and event-driven integrations.
• Introduce CDC and near-real-time data patterns where possible.
• Work with data warehouse/lakehouse environments.
• Make architectural decisions around scalability, security and performance.
• Improve automated testing, CI/CD and observability.
• Take engineering work from initial design through to production.
• Mentor engineers and contribute to backend standards.
• Collaborate with technical and non-technical stakeholders on a defence programme.

Skills

Java

SQL

Backend services

REST

Event-driven architecture

Systems integration

Data warehouse/lakehouse

CI/CD

Observability

Security & architecture

Job description

Senior Software Engineer – UK Defence Programme

Bath | Hybrid – typically 3 days onsite

Permanent

UK National / SC Clearance Eligible

We’re looking for an experienced Senior Backend Engineer to join a major, multi-year technology transformation programme within UK defence.

This is a hands-on engineering role with genuine technical ownership. You’ll be building and evolving a complex software platform and connecting it with a growing ecosystem of systems including data lakehouse technology, ERP platforms, optimisation engines and external partner platforms.

Much of the technical landscape is still being designed, so this is ideal for an engineer who enjoys taking loosely defined requirements, shaping the solution and delivering it through to production.

What You’ll Be Doing

• Design and build backend services and APIs.
• Develop complex integrations with ERP systems, data platforms and external technologies.
• Work primarily across Java, SQL and modern data/integration tooling.
• Design REST and event-driven integrations.
• Introduce Change Data Capture (CDC) and near-real-time data patterns where appropriate.
• Work with data warehouse/lakehouse environments.
• Make technical decisions around architecture, scalability, security and performance.
• Improve automated testing, CI/CD and observability.
• Take substantial pieces of engineering work from initial design through to production.
• Mentor engineers and contribute to wider backend engineering standards.
• Work with technical and non-technical stakeholders across a major defence programme.

What We’re Looking For

You’ll ideally be an experienced Senior Software Engineer with strong backend, integration and data experience.

Key experience:

• Java or a comparable backend language
• Strong SQL
• Backend services and API development
• REST and/or event-driven architecture
• Systems integration
• Data warehouse/lakehouse integration
• CI/CD and automated testing
• Observability and production monitoring
• Strong system and data design knowledge
• Third-party platform / ERP integration

Experience with streaming technologies, Change Data Capture (CDC), data pipelines or near-real-time integrations would be particularly valuable.

We’re looking for someone comfortable working with ambiguity who can understand the underlying problem, make pragmatic technical decisions and take ownership of delivering the solution rather than relying on a fully defined specification.

Defence & Security Requirements

Due to the nature of the programme, candidates must be UK nationals and eligible to obtain UK Security Clearance (SC).

Existing active SC clearance would be advantageous but isn't essential for candidates who meet the eligibility requirements and are willing to undergo the clearance process.

Experience within defence, central government, public safety or another regulated environment would also be beneficial.

Bath-based with hybrid working, typically around three days per week onsite at either the company office or customer locations.

Benefits include:

• Competitive salary with annual reviews
• Enhanced family leave
• 25 days annual leave plus bank holidays
• Life assurance
• Company social events

Why Consider the Role?

This is an opportunity to take genuine Senior-level ownership within a significant, long-term UK defence technology programme.

You'll work on complex production systems and integrations while having the freedom to influence architecture, technology choices and engineering standards.

It would particularly suit a backend engineer who wants to remain hands-on while solving challenging integration and data problems at scale.

Interview Process

The process is expected to include:

• Hands-on programming session

The programming exercise can be completed in a suitable language such as Java, C#, TypeScript, Python or Go.