Senior Java Engineer - Perm or Contract

Our 'black belt' specialists are leaders in their domains: digital champions, delivery-focused experts, top-tier security professionals, AI thought leaders, and engineering best practice advocates.

With a global footprint and deep local insight, Software at Scale delivers cutting-edge technology solutions that power mission-critical platforms. We solve complex engineering challenges at scale, driving quality, performance, and resilience through the strength of our people.

The Role & The Challenge

We are seeking an exceptional, highly proactive Senior Java Engineer who thrives in a high-trust, fully empowered environment. This is a purely hands-on execution role for a seasoned technologist who possesses deep internal knowledge of the modern Java ecosystem.

A critical focus of this mandate is building and optimising Software as a Service (SaaS) platforms designed to scale out horizontally.

We do not micromanage, nor do we hand out pre-packaged answers. You will step into an environment where you are expected to take complete technical ownership, architect high-throughput distributed systems, and navigate complex enterprise constraints.

You are not just a solo brilliant coder; you are a foundational team player. You will lead by example, establishing engineering baselines, and naturally providing the technical mentorship needed to lift the engineering capabilities of the squads around you.

Key Responsibilities

• SaaS Architecture & Scale-Out: Architect, build, and optimise multi-tenant SaaS platforms, ensuring the architecture can dynamically and horizontally scale out to handle massive concurrency and data volume.
• API Engineering: Design and build high-performance, resilient RESTful APIs and event-driven microservices using modern Java frameworks.
• Technical Leadership & Team Uplift: Actively mentor and elevate mid-level engineers through collaborative code reviews, pair programming, and architectural whiteboard sessions.
• Java Ecosystem Development: Utilise the latest Java LTS releases and enterprise frameworks (specifically Spring Boot and Spring AI) alongside robust build tools (Maven or Gradle).
• DevOps & Testing: Develop and maintain frictionless CI/CD pipelines. Implement rigorous automated testing (JUnit, Mockito) and containerised workflows using Docker.
• Cloud-Native Deployment: Leverage AWS-native services to deploy reliable, horizontally scalable Java applications.
• AI Tooling Adoption: Champion the adoption of GenAI and agentic tools where they tangibly improve engineering productivity, code quality, or system capability.
• Observability: Apply observability best practices using modern monitoring, logging, and tracing tools to proactively manage system performance and identify bottlenecks.

What You Bring

• SaaS Scaling Expertise: Mandatory commercial experience designing and engineering Software as a Service (SaaS) platforms that are explicitly built to scale out horizontally under heavy load.
• Java Mastery: Deep, hands-on expertise in modern Java (e.g., Java 17 or 21). You understand the JVM internals, memory management, and concurrency.
• Frameworks & Build Tools: Extensive commercial experience with the Spring ecosystem (Spring Boot, Spring Data, and ideally Spring AI), alongside mastery of Maven or Gradle.
• Proactive Execution: A proven history of hunting down answers, researching architectural trade-offs independently, and proposing fully formed solutions rather than waiting for top-down direction.
• Cloud & CI/CD: Experience deploying and operating Java workloads on AWS, managing CI/CD pipelines, and working with Docker containers.
• Communication: Strong communication skills and a collaborative, execution-driven approach to solving enterprise problems.

What We Offer

• Meaningful, hands-on engineering work across complex, enterprise-grade SaaS platforms.
• Clear growth pathways from Senior to Staff and beyond.
• A low-ceremony, delivery-focused environment that values engineers who own outcomes.
• Competitive remuneration and benefits.
• The opportunity to work alongside highly experienced engineers on challenging, high-impact systems.