Top Software Engineer Jobs in Belfast

Join ROOST's Coop project to design, implement, test, document, and release trust-and-safety features. Work across backend APIs, GraphQL, databases, and UI to improve reviewer workflows, detection integrations, and reporting. Lead code quality, security practices, community contribution reviews, and stakeholder coordination while engaging with users and the open source community.

Join the ROOST Osprey team to design, implement, test, and maintain a high-performance, real-time safety rules engine. Work includes building data/event pipelines, scaling and containerizing services, integrating with Kafka and gRPC, reviewing community contributions, maintaining code quality and security, and engaging with users and open source contributors to prioritize and deliver features.

As a Software Engineer, you will build and maintain financial platforms and applications that help homeowners track and manage their expenses, collaborate with the engineering team, and utilize AI for data insights.

As a Backend Software Engineer, you'll develop and maintain REST APIs using Django, manage cloud infrastructure, and oversee CI/CD pipelines to support consumer fintech applications.

Lead technical teams to design, build, test, and maintain modern, scalable, secure software. Provide technical ownership for product architecture, estimation, planning and requirements. Coach and develop junior staff, drive CI/CD practices, troubleshoot live applications, and liaise with customers as the teams technical leader.

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.

Design and build distributed backend services for the cloud monetization platform, focusing on correctness, consistency, scalable microservices, distributed transactions, and reliable asynchronous workflows. Influence system architecture, own service implementations, and collaborate across teams to support billing, reservations, payments, and revenue flows.

Build and maintain integrations for North's agentic platform, own the end-to-end integration pipeline, create evals and tests to ensure reliability, tune tool descriptions, and help other engineers add and maintain integrations while using AI responsibly to improve performance and quality.

Lead development of the Live View feature for iOS, build mobile apps that integrate with devices, collaborate cross-functionally, contribute to architecture and design, and follow full SDLC practices including code reviews, source control, testing, and operations.

Develop data extraction and manipulation pipelines, use AI models and NLP (e.g., ChatGPT APIs) to analyze and match available luxury items to customer requests and sales orders, and collaborate to improve matching accuracy and processing efficiency.

Work as an embedded QA engineer for Unity Studio performing manual and exploratory testing, owning QA processes from requirements to sign-off, writing and maintaining test cases, managing defect lifecycles, collaborating with engineers/product managers, participating in agile ceremonies, and contributing to quality process improvements.

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

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.

Lead design and development of Windows desktop applications. Ensure performance, maintainability, and accessibility, while driving feature lifecycle and collaborating cross-functionally.

We are seeking a collaborative Backend Engineer with Java expertise to design, build, and maintain backend services, focusing on operational excellence and system reliability. Responsibilities include architecture, automation, and supporting production environments in a multi-cloud setting.

The Senior Software Engineer will lead the development of backend systems for payment processing, collaborating with teams, setting goals, and fostering quality and ownership in code development.

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.

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.

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.

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.

Lead quality engineering across the software lifecycle by designing scalable automated testing frameworks, developing API and UI automation, improving CI/CD testing infrastructure, researching AI-enabled testing approaches, defining test strategies and metrics, and mentoring engineers. The role requires strong programming, cloud, database, automation, and cross-functional collaboration skills in a hybrid Belfast fintech SaaS environment.

Build and maintain scalable, reliable agentic AI systems for biomedical research, integrating LLMs, tool-calling, and data platforms. Drive technical decisions, optimize analytical workflows, deploy agents on the data platform, mentor teammates, and participate in on-call rotation to ensure performance, security, and continuous improvement.

Analyze and optimize ClickHouse database performance, develop performance tests, support engineering teams, collaborate with core teams, and engage with the open-source community.

Customer-embedded principal software engineer driving production-grade solutions for strategic accounts. Translate business needs into technical designs, build and deploy end-to-end systems, influence senior stakeholders, and transition work to FDE crews. Operate in ambiguous, fast-paced environments with strong ownership, industry context, and an entrepreneurial mindset to deliver measurable business outcomes.

Lead the design and development of complex Rails features, mentor junior engineers, define technical direction, and ensure high-quality code while collaborating with stakeholders.