Top Software Engineer Jobs in Belfast

Develop and maintain full-stack web applications using C#, .NET (including .NET 8), Blazor and Angular 15. Build APIs, integrate databases (MySQL, SQL Server, MongoDB), write tests, perform code reviews, optimize queries, document systems, and collaborate in Agile teams to deliver high-quality solutions.

Execute scheduled, ad hoc, and release-milestone software tests; review test cases; report defects in issue-tracking systems; communicate status in standups; and collaborate with software test managers and development teams. The role requires knowledge of QA methodologies, black-box, grey-box, and white-box testing, strong communication and organization, independent and team-based work, and participation in planning and professional meetings.

Lead design and implementation of the Libraries Platform: services, pipelines, package index, automation for builds, CVE remediation, SBOM/provenance, AI-assisted patching, and reliability/observability for multi-ecosystem package workflows.

Build and evolve Python-based paid media and personalisation services for web, mobile, email, push, and paid social channels. Develop scalable campaign delivery systems, integrate advertising platforms, automate audience activation and budget optimisation, and improve performance through experimentation, attribution, and measurement frameworks. Use large-scale data to drive relevance, media efficiency, return on ad spend, and other commercial outcomes while partnering with marketing, media, engineering, and data science teams.

Leads technical direction and delivery of scalable, secure software projects. Designs and implements solutions, collaborates with product stakeholders, drives coding standards and engineering excellence, mentors and supports engineers, contributes to hiring, influences technology adoption, and owns product and feature deployment and ongoing support.

Lead full lifecycle delivery of cloud-based web features: design, build, test, release, and operate reliable, scalable systems. Own technical direction, convert ambiguous problems into plans, reduce technical debt, and use observability and metrics to ensure performance and health.

Build and evolve Python services powering scalable paid media and personalization campaigns across web, mobile, email, push, and paid social. Develop integrations for audience activation, bidding, and budget management; implement experimentation, attribution, and measurement frameworks; and use large-scale data to improve marketing performance, spend efficiency, and customer outcomes.

Architect and build production AI-powered HR systems using agentic workflows, multi-agent systems, APIs, and workflow automation. Integrate Workday and other HR tools, implement governance, audit logging, privacy controls, and human approval gates, and ensure reliable payroll-adjacent workflows. Document solutions, train People team users, drive adoption, and measure automation impact. The role requires strong software engineering, AI application development, HR technology, Workday, data privacy, and workflow automation experience.

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.

Lead design, implementation, and end-to-end delivery of high-quality web features. Build and operate cloud-native services, write and review well-tested code, use observability and metrics, reduce technical debt, and align implementations with team architecture and scalability needs.

Design, build, and evolve backend-focused experimentation platform services, APIs, automation, and developer tooling. Set technical direction, champion a self-service model, ensure production readiness (observability, resilience), partner with product and engineering teams, mentor engineers, and document APIs and operational processes.

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.

Design, build and evolve backend-focused experimentation platform capabilities (APIs, services, automation, developer tooling). Set technical direction and standards, enable a self-service model, partner with product and engineering teams, mentor engineers, and ensure production readiness with observability, resilience, and clear documentation.

Deploys, supports, and improves software products and services while maintaining customer satisfaction and SLA performance. Responsibilities include investigating and resolving tickets, managing delivery requirements, preparing estimates and quotes, coordinating with development teams, identifying product and support improvements, managing risks, protecting customer information, and adhering to GDPR and information security requirements. The role is primarily remote with occasional travel to Leicester offices and customer sites.

Build and ship native Android features using Kotlin and Jetpack Compose. Design clean user flows for financial services, integrate backend APIs, improve performance and stability, use analytics and production feedback, and implement AI-assisted on-device experiences where beneficial.

Design, build, and operate scalable cloud-native SaaS products using full-stack engineering practices. Drive platform modernization, API-first architecture, microservices, testing, deployment, and engineering excellence. Partner with Product and Design to solve customer problems, contribute to technical strategy, mentor engineers, and promote modern DevOps, CI/CD, observability, and automation practices.

The Lead Software Engineer will oversee development in abuse and fraud prevention, lead teams, design systems, and ensure high-quality outcomes.

Develop and maintain NedGraphics cloud products (OptiNedLink), build serverless AWS backends, design secure REST APIs and event-driven workflows, implement automated testing, optimize performance and scalability, enforce security best practices, integrate third-party APIs and ERP/PLM systems, and produce developer documentation and API specifications.

The Senior Full-Stack Engineer will design and build scalable UI systems, collaboratively own features, and support production quality. Responsibilities include API design, debugging, and performance tuning.

As a Software Engineer, you will build features, write maintainable Roblox Lua code, collaborate with teams, and enhance gameplay for millions of players.

The Sr. Software Engineer will design, develop, and maintain public APIs and integrations, ensuring high scalability and performance while improving code quality using AI tools.

As a Software Engineer in Sustaining Engineering, you will resolve complex issues related to Ubuntu and open-source software, engage with upstream communities, and develop bug fixes while maintaining close collaboration with support and product teams.

As a Python and Kubernetes Software Engineer, you will develop data analytics solutions using open source tools, collaborating with a distributed team.

The software engineer will develop and operate backend services for Snap Store and Charmhub.io, focusing on clean APIs and feature implementation.

The role involves developing software for Linux-based systems on autonomous devices, optimizing performance and ensuring reliability in various hardware environments.