Principal Java Engineer

Principal Java Engineer (Backend) - Scale-Up Security Tech - Remote/Hybrid (Ireland/NI)

€105-111k + 10% bonus + Equity
Event-Driven Microservices | Java | AWS | Hands-on Leadership

An innovative scale-up is looking for a Principal Java Engineer to help them re-architect a critical platform used by law enforcement, emergency response, and global enterprise retailers.

With $30 million Series A funding secured, they're scaling fast - across the UK, Ireland, the US, and Middle East - and building out their in-house software capability after years of outsourced development. You'll play a key role in rebuilding their platform from a monolithic legacy system to a modern, event-driven microservices architecture hosted on AWS.

What you'll do

• Lead the design and build of scalable Java microservices in an event-driven architecture

• Help re-architect a platform used by thousands of users globally - high visibility, high impact

• Work closely with product, QA, design, and senior engineering leadership

• Provide hands-on coding, technical mentoring, and code reviews

• Champion best practices in software design, performance, and system reliability

• Be a key voice in technical strategy and architecture discussions

About you

• 6+years' experience with Java and Spring Boot, strong backend focus

• Currently in a Principal, Staff or Tech Lead hands-on role

• Expertise in microservices and event-driven systems (Kafka, SNS/SQS, etc.)

• Solid cloud experience in AWS

• Experience breaking down monoliths into distributed systems

• Comfortable in fast-paced scale-up environments - wearing multiple hats when needed

• Strong communicator with a collaborative mindset

• Bonus: exposure to C/C++ (due to the hardware element of the product)

What's on offer

• €105-111k base salary

• 10% bonus + Equity/Share Options

• Private healthcare after 25+ days

• No pension currently offered

• Flexible hybrid working - 1 day/week in Belfast HQ with occasional Dublin visits

Why join?

You'll be joining a high-growth tech scale-up on a mission to improve public and workplace safety through cutting-edge hardware and software. It's an opportunity to do meaningful technical work, influence architecture, and help shape a product that's making a real-world difference - all while working alongside smart, supportive people in a down-to-earth team.

To speak in absolute confidence about this opportunity please contact Jack Tyrrell, Specialist Recruitment Consultant at MCS Group 016994371or send an up to date CV via the link provided.

If this position is not right for you, we may have others that are. Please visit www.mcsgroup.jobs to view a wide selection of our current jobs. All conversations will be treated in the strictest of confidence.