Senior Software Test Engineer jobs in Cardiff

About the Job This position is for a Senior Software Engineer with a minimum of 5 years of experience in backend development and a passion for building robust, scalable systems. We are looking for an engineer with a strong background in the C# .NET ecosystem, and a preference for candidates with significant experience on AWS. Are you ready for a challenge? We’re looking for a dynamic software...

You will join a cross-functional product engineering team working on the evolution and modernisation of a core SaaS platform. The focus is on building scalable, cloud-native services while improving reliability, performance, and long-term maintainability.

You will be working closely with the Machine Learning team; however, you are not required or expected to have background in Machine Learning. This is an applied role, and we are looking to hire a software engineer with experience in cloud computing and distributed systems. In this role, you will:

You will design and deploy robust frontend client, backend services, infrastructure automation, and cloud-native solutions by utilising your software development knowledge and your DevOps proficiency across AWS and GCP.

Senior/Lead Software Engineer – Fully Remote (UK) A global B2B SaaS technology business is building out its European engineering hub and is hiring multiple Senior / Lead Software Engineers (JavaScript) to develop and enhance a mission-critical platform used internationally. These are hands-on individual contributor role with strong ownership — ideal for engineers who enjoy building high-quality...

At the heart of Paxton, we are innovators, we look for ways of harnessing new technology to provide better solutions for our customers. We're a global brand with nearly 40 years of experience, our team of over 400 employees is spread around the world. We pride ourselves on creating a vibrant environment, with a focus on excellent company culture. xujxxms Our teams make Paxton a great place to...

I'm partnered with an early-stage, post-revenue AI startup is building an end-to-end operating system to help businesses detect and resolve complex B2B issues before they become costly or disruptive. The product is already being used by large enterprises across multiple industries, and demand is growing fast - hence this hire! Backed by a top-tier European venture fund, the company is tackling a...

You should be comfortable with most of our core technologies:

Senior Backend Engineer | Fully Remote UK | £70,000-£75,000 | Python | Django | AWS Location: Fully Remote - Candidates MUST be UK based Salary: £70,000-£75,000 + benefits Tech Stack: - Backend: Python (Django) - Frontend: React - Cloud Systems: AWS, Docker Are you a Senior Backend Engineer who enjoys taking ownership of real production systems and shaping how a platform evolves as it...

Senior Full Stack Engineer Remote (UK) | Full time London office available for optional in person collaboration We’re looking for an experienced Senior Full Stack Engineer to join a small, highly skilled team building a next generation Financial Services Regulatory Compliance platform. This is a hands on role where you’ll work across the stack, leading frontend development with React and...

Job Description Electronics Engineer (Design/ Test)£43,000 - £58,000 + Autonomy/ Leading Teams + Career Progression With No Ceiling + Further Technical Training + 32 Days Holiday + Up to 10% Pension & Benefits Package +Commutable from Cardiff, Newport, Caerphilly, Nantgarw, Penarth, Pontyclun, BedwasAre you an Electrical/ Electronic Engineer, Electrical/ Electronic Design Engineer, Electrical/...

About Prighter Prighter is a fast-growing LegalTech company building productised services and SaaS solutions for compliance with data protection as well as AI & digital governance regulations. With the mission to enable companies around the world to comply with regulatory requirements for their digital business, our services and SaaS solutions guide our global clients through the increasingly...

🚀 About Webigence and Spark Travel Webigence has 25 years of experience crafting UX‑first, often highly complex software. Our engineers pair forward‑thinking agile practices with an obsession for intuitive design, shipping products that feel effortless even when the logic underneath is anything but. Alongside a handful of long‑standing third‑party clients, we’re scaling our own SaaS...

About The Role Deadline for applications: 11:59pm on 31st October 2025 Were looking for a Principal Software Engineer to shape the technical direction of high-profile projects and lead the delivery of modern, scalable software. Please read the following job description thoroughly to ensure you are the right fit for this role before applying. We use technology to create impactful, human-centred...

Key Responsibilities - Design, implement, and maintain software for nuclear systems, ensuring compliance with safety and regulatory standards. - Develop software for reactor control, monitoring systems, data acquisition, simulation, and predictive analytics. - Collaborate with multidisciplinary teams including nuclear engineers, electrical engineers, and safety specialists. - Apply best...

Software Engineer – £65,000–£85,000 + Equity – Remote (UK) - London office if preferred The Opportunity 💻 Join a fast-growing, AI-native software company building workflow automation tools used daily by thousands of professionals across people-heavy industries. The platform removes manual, repetitive work through AI, automation and thoughtful product design, helping teams move faster and focus...

You will design and build APIs that enable products, partners and AI services to work together, including: Building RESTful APIs using C# .

You will likely bring: Strong experience building backend services in C# .

Principal Software Engineer Fully Remote | Permanent | Competitive Salary + Benefits Harrington Starr has partnered with a leading Global Payments Technology company who are seeking to hire a Principal Software Engineer to join their senior engineering leadership team. This is a rare opportunity to combine hands-on development with strategic influence, guiding architecture decisions and shaping...

You will be working with a high-calibre team of young, talented professionals who share a like-minded mindset, delivering top-tier implementation and technical services to clients.

Join OCI’s Edge Security team as a Principal Engineer to architect and deliver cloud-scale DDoS protection. You’ll lead design for high-performance detection and mitigation systems, drive automation and operational excellence, and set the technical direction for customer-facing DDoS capabilities across OCI’s global edge. This role requires deep expertise in Linux networking data path and...