Senior Java Software Engineer

NPA WorldWide; Cardiff; Hybrid; GBP 60,000 - 90,000; Full time

Job summary

A mission-driven consultancy in Cardiff seeks a Principal Software Engineer (Java) to lead the design and development of secure software solutions for the UK Government and Defence. This role is ideal for an engineer passionate about shaping engineering best practices while contributing to hands-on development. You will oversee projects involving modern technologies and cloud-native solutions, ensuring robust and user-focused systems. The opportunity offers competitive salary packages, flexible working arrangements, and clear paths for career progression.

Benefits

Flexible working

Learning & development budget

Private healthcare

Matched pension scheme

Monthly socials

Clear career progression

Qualifications

• Deep expertise in Java, with strong full-stack engineering skills.
• Proven experience leading teams or projects at a senior/principal level.
• Strong knowledge of system architecture, cloud solutions, and API design.
• Familiarity with DevOps tools and automation (CI/CD, containers, IaC).

Responsibilities

• Lead the design, development, and testing of secure, scalable systems using Java.
• Architect and maintain APIs, data pipelines, and cloud-native solutions.
• Drive adoption of DevOps practices including CI/CD.
• Guide and mentor engineers while promoting best practices.

Skills

Java

Full-stack engineering

System architecture

Cloud solutions

API design

DevOps tools

Agile methodologies

Stakeholder engagement

Job description

Job description : Our client, a

• mission-led consultancy
• , is looking for an experienced
• Principal Software Engineer
• (Java) to join their growing team. They deliver
• secure, modern software solutions
• to the UK Government and Defence sectors, enabling clients to build
• scalable systems
• and
• progressive web applications
• that drive real impact.

This is a senior-level opportunity for a hands-on engineer who enjoys

• leading by example
• , thrives in
• agile environments
• , and is passionate about shaping
• engineering best practice
• while still contributing to the codebase.

Key Responsibilities

• Lead the design, development, and testing
• of secure, scalable systems using Java with modern front-end frameworks (e.g., React)
• Architect and maintain
• APIs, data pipelines, and cloud-native solutions
• (AWS, Azure, private cloud)
• Drive adoption of
• DevOps practices
• CI / CD, containers, infrastructure-as-code
• Guide and mentor engineers, promoting
• best practice, clean coding, and agile delivery
• Collaborate with stakeholders and clients to
• shape technical direction
• and ensure robust, user-focused solutions
• Contribute across the
• full software development lifecycle
• , from discovery to production support

Essential Skills & Experience

• Deep expertise in
• Java
• , with strong full-stack engineering skills
• Proven experience
• leading teams or projects
• at a senior / principal level
• Strong knowledge of
• system architecture
• , cloud solutions, and API design
• Familiarity with
• DevOps tools and automation
• (CI / CD, containers, IaC)
• Track record of delivering
• secure, production-grade systems
• in agile teams
• Excellent stakeholder engagement, influencing, and communication skills

Desirable

• Background in
• secure or classified environments
• Knowledge of
• ITSM
• or systems within the
• government / defence sector
• Experience balancing
• technical leadership with hands-on development

Whats in It for You

• Flexible working
• 37.5 hrs / week with remote and hybrid options
• Learning & development budget
• for training, certifications, and conferences
• Private healthcare
• & matched
• pension scheme
• Monthly socials
• and
• quarterly company meetups
• Clear
• career progression
• into leadership roles in a high-impact sector

Diversity & Inclusion

Our client is an equal opportunities employer and a Disability Confident organisation, committed to fostering a workplace where diverse perspectives are celebrated and everyone can thrive.

How to Apply

If youre an experienced Principal Software Engineer with expertise in Java, and youre excited to help deliver solutions that truly matter, wed love to hear from you.

Qualifications

• Deep expertise in
• Java
• , with strong full-stack engineering skills
• Proven experience
• leading teams or projects
• at a senior / principal level
• Strong knowledge of
• system architecture
• , cloud solutions, and API design
• Familiarity with
• DevOps tools and automation
• (CI / CD, containers, IaC)

Why is This a Great Opportunity

• Flexitime
• 37.5 hrs / week structured your way + remote options
• Learning budget
• for training, certifications, and conferences
• Private healthcare
• and
• matched pension
• Monthly socials
• and quarterly company meetups

Career growth in a fast-moving, meaningful sector

Salary Type: Annual Salary
Salary Min: £ 60000
Salary Max: £ 90000
Currency Type: GBP