Top Software Engineer Jobs in Belfast

The Software Test Engineer at Citi will focus on automation testing, creating test plans and cases, and ensuring quality through rigorous testing practices across applications.

The Software Engineer will design, develop, and support the MEMX Trading system software, focusing on production support during US evening hours.

Build and operate production custody systems: signing service, key management, chain integrations, and transaction pipelines. Own end-to-end subsystems, integrate new chains, collaborate with cryptography on threshold signing and key recovery, write post-mortems, and produce clear async design docs and PRs.

Build and own end-to-end backend systems for forecasting and agentic LLM research: design, deploy, monitor, debug, and harden features and pipelines (benchmarks, agents, production services). Prototype quickly, work with LLM APIs and coding agents, and collaborate with researchers to improve evaluation and forecasting tools.

Design, build, and ship production-ready software; decompose ambiguous problems into system architectures; modernise legacy systems and develop greenfield features; own technical decisions, testing, observability, and documentation; collaborate with product and design and ensure operational readiness.

Build and maintain scalable cloud-based data management and processing systems for biomedical research. Own platform components end-to-end, drive architecture and standards, improve CI/CD, observability, security, performance, mentor engineers, and participate in on-call incident response.

Design and evolve systems for Motion's infrastructure, focusing on reliable and secure operations across APIs, Linux systems, and cloud environments with a focus on hands-on coding and engineering judgment.

Lead technical strategy and delivery for Revenue Intelligence systems across web apps, backend APIs, event-driven services, data pipelines, analytical stores, and ML recommendation workflows. Improve reliability, security, scalability, and observability while remaining hands-on in design, implementation, incident response, and mentoring to raise organizational engineering effectiveness.

Lead cross-product engineering work: design APIs and data models, turn ambiguous customer problems into technical plans, implement and roll out features across web, APIs, CLI, integrations, and infra, debug production issues, and raise engineering quality through docs, reviews, and mentorship.

As a Frontend Engineer, you'll craft user interfaces, write engineering requirement documents, build test suites, and integrate analytics for product success.

As a Backend Engineer, you will design scalable APIs, create Engineering Requirement Documents, and build test suites for product analytics and performance.

Lead technical strategy and delivery for Supply Chain & Logistics systems, designing and operating scalable, reliable warehouse software. Mentor engineers, promote engineering best practices, influence architecture and technology investment, and drive DevOps, observability and continuous improvement across platforms.

Design, build, test and maintain high-quality Android applications using Kotlin and Jetpack Compose. Provide technical leadership, mentor engineers, drive architectural decisions, optimize Gradle builds, contribute to CI/CD with GitHub Actions, and collaborate with designers, backend engineers and product managers to deliver performant, accessible, offline-first mobile experiences.

Lead design and delivery of scalable, resilient backend systems and integrations. Provide technical leadership, conduct code reviews, ensure automated testing and observability, mentor engineers, collaborate with stakeholders, and drive operational excellence for cloud-native applications.

Own, build and maintain scalable Loyalty platform services for Sparks. Deliver end-to-end features from design to deployment, improve developer experience, and support live services with reliability, observability, and operational excellence across distributed, cloud-native systems.

Design, build, test and maintain high-quality Android applications using Kotlin and Jetpack Compose. Provide technical leadership, mentor engineers, drive architectural decisions and best practices, optimise Gradle builds and CI/CD pipelines, and collaborate with designers and backend teams to deliver performant, accessible, offline-first mobile experiences.

Lead design and delivery of scalable, cloud-native backend systems and integrations. Provide technical leadership, conduct code reviews, champion testing and observability, mentor engineers, collaborate with stakeholders, and drive operational excellence.

Ownership of backend Loyalty platform services: design, build, deploy, monitor and optimise scalable, distributed systems. Collaborate across teams to shape technical direction, improve developer experience, and maintain reliability, observability and operational excellence for customer-facing Sparks journeys.

Lead technical design and delivery of supply chain and warehouse software at scale. Drive architecture, DevOps, observability, reliability and performance practices; mentor senior engineers; influence product and technology strategy; promote clean code and engineering excellence across teams; support recruitment and outreach.

Join the k6 core team to design, implement, and maintain k6 (written in Go). Deliver production-quality features, maintain reliability and performance, work on distributed/cloud components, collaborate on design and code reviews, and engage with the open-source community.

Lead design and implementation of scalable AI-centric systems for offensive security, develop agentic AI capabilities (LLMs, RAG), own feature lifecycle to production, mentor engineers, run design reviews, and integrate AI into microservice architectures with cloud, container, and messaging technologies.

Design, implement, and maintain full-stack web features for a dairy farm management system. Own development lifecycle, ensure quality and reliability, support customers and technicians, and collaborate across cross-functional teams.

Build and ship native Android features in Kotlin for an AI-enabled neobank. Design clean mobile flows for payments, insurance and financial services, integrate backend APIs, improve performance and reliability, use analytics and on-device ML (TensorFlow Lite) to enhance user journeys, and collaborate with product and design.

Responsible for building scalable distributed systems, mentoring teammates, innovating on technical solutions, and improving team processes. Requires expertise in backend languages, especially Golang and Typescript.

Responsible for the technical deployment of the Guardian system, ensuring it meets requirements, integrating with client environments, and managing customer communications.