Staff Full Stack Engineer

Sellick Partnership; Bath; Hybrid; GBP 90,000 - 120,000; Full time

Benefits offered by this job

Salary reviews and bonuses

Enhanced leave

Life assurance

Company social events

Job summary

Sellick Partnership seeks a Staff Full-Stack Engineer for a major UK defence programme, based around Bath with a hybrid pattern (approximately three days onsite per week).

You'll take technical ownership, lead architectural discussions and design integrations across data, APIs and external platforms while hands-on coding in Java/Angular. This role combines senior technical ownership with mentorship and fast-paced delivery in a regulated environment.

Responsibilities

• Take technical ownership of substantial areas of a large-scale UK defence technology programme.
• Design and build integrations between a core software platform and external systems including ERP platforms, data lakehouses, optimisation engines and partner technologies.
• Build and evolve backend services, APIs and user-facing functionality.
• Work across a modern technology stack including Java, SQL and Angular.
• Design REST and event-driven integrations and introduce streaming or Change Data Capture (CDC) patterns where appropriate.
• Lead technical design sessions and help shape architecture across data, integrations and APIs.
• Make architectural decisions around scalability, maintainability, security and performance.
• Improve engineering standards across automated testing, CI/CD, observability and code quality.
• Remain hands-on with development while taking increasing responsibility for technical leadership.
• Mentor Senior and other Engineers, helping develop engineering capability across the team.
• Work directly with technical and non-technical customer stakeholders, explaining complex engineering decisions clearly.

Skills

SQL

Data engineering

Backend services

APIs

REST

Event-driven

Systems integration

ERP integration

Angular

Data lakehouse

CI/CD

Observability

Monitoring

Java

Job description

Staff Full-Stack Engineer – UK Defence Programme

Bath | Hybrid – typically 3 days per week onsite

Permanent

UK National / SC Clearance Eligible

We’re recruiting for an experienced Staff Full-Stack Engineer to join a major, multi-year technology transformation programme within UK defence.

This is a senior hands-on engineering position with significant technical ownership. You’ll act as a technical lead within the team, helping shape a complex software platform and its integration 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, making this an opportunity for someone who enjoys solving open-ended engineering problems rather than simply delivering against predefined specifications.

You’ll work predominantly across backend engineering, data and integrations while remaining comfortable working across the full stack. You’ll lead through technical influence rather than formal management, working closely with Engineering, Product and Delivery leadership.

What You’ll Be Doing

• Take technical ownership of substantial areas of a large-scale UK defence technology programme.
• Design and build integrations between a core software platform and external systems including ERP platforms, data lakehouses, optimisation engines and partner technologies.
• Build and evolve backend services, APIs and user-facing functionality.
• Work across a modern technology stack including Java, SQL and Angular.
• Design REST and event-driven integrations and introduce streaming or Change Data Capture (CDC) patterns where appropriate.
• Lead technical design sessions and help shape architecture across data, integrations and APIs.
• Make architectural decisions around scalability, maintainability, security and performance.
• Improve engineering standards across automated testing, CI/CD, observability and code quality.
• Remain hands-on with development while taking increasing responsibility for technical leadership.
• Mentor Senior and other Engineers, helping develop engineering capability across the team.
• Work directly with technical and non-technical customer stakeholders, explaining complex engineering decisions clearly.
• Collaborate with engineers, project managers, designers and senior stakeholders across the wider programme.

What We’re Looking For

You’ll ideally be an experienced Senior/Staff-level Full-Stack Engineer with a strong backend focus and experience taking ownership of complex technical work.

Key experience includes:

• Strong SQL and data engineering knowledge.
• Experience building backend services and APIs.
• REST and/or event-driven architecture.
• Systems integration experience.
• Experience integrating third-party platforms, ERP systems, data platforms or external services.
• Angular or experience with a comparable modern front-end framework.
• Data warehouse and/or data lakehouse integration experience.
• CI/CD and automated testing.
• Observability and production monitoring.
• Strong understanding of system and data architecture.
• Experience with streaming, messaging or event-driven technologies would be beneficial.
• Change Data Capture (CDC) knowledge would be advantageous.

Candidates coming from another strong backend language such as C#, Python, Go or TypeScript may also be considered where they are comfortable transitioning into Java.

Beyond the technology, we’re looking for someone comfortable acting as a team’s technical point of reference. You should be able to take an ambiguous requirement, define the underlying problem, make pragmatic technical decisions and lead the solution through to production.

Previous Staff Engineer experience isn’t necessarily essential if you’re a strong Senior Engineer already operating with Staff-level technical ownership.

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 is not essential for candidates who meet the eligibility requirements and are willing to undergo the clearance process.

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

Location & Working Pattern

The position is based around Bath and operates on a hybrid model, typically requiring approximately three days per week onsite at either the company office or customer locations.

The exact working pattern may vary depending on programme requirements.

• Competitive salary with annual reviews
• Enhanced maternity, paternity and adoption leave
• 25 days annual leave plus bank holidays
• Life assurance
• Company social events

Why Consider the Role?

This is an opportunity to take genuine Staff-level ownership within a significant UK defence technology programme rather than simply delivering individual backlog tickets.

You’ll help determine how systems are designed, integrated and operated, while remaining close to the code.

The programme involves complex, real-world production systems used to support organisations operating within defence, public safety and resilience.

For an engineer who enjoys solving difficult technical problems, influencing architecture and mentoring other engineers while remaining hands-on, this offers considerable scope and long-term technical ownership.

Interview Process

The process is expected to include:

• Hands-on programming session
• System design and architecture discussion
• Technical leadership and mentoring discussion

The core environment uses Java and Angular, although candidates may be able to complete the programming exercise using another suitable language such as C#, TypeScript, Python or Go.