Principal Software Development Engineer in Test (SDET)

Join Capco as a Principal Software Development Engineer in Test (SDET) where you will lead the design, development, and implementation of automated testing frameworks. You will work closely with cross-functional teams to ensure the highest quality of software delivery while driving innovation and efficiency in testing methodologies.

Transform the Future of Finance with Us!At Light, we are on a mission to revolutionize the outdated ERP systems of the factory era with our dynamic Smart Financial Platform. We empower modern, global businesses with capabilities like automated accounting, real-time reporting, and agile financial flows that adapt to the pace of business.Our approach is collaborative; we develop alongside our customers, deliver swiftly, and are passionate about our craft. In a short span, Light has evolved from a concept to the backbone of renowned companies such as Lovable, Legora, and Keyshot. Users don’t just utilize Light—they truly enjoy the experience.As part of a pioneering team, we are defining a new category in software. Imagine engineers who are passionate about finance, designers who prioritize reconciliation, and operators who view finance as a product. If you are keen on modernizing the way the world manages money—one workflow at a time—you’ve found your place.Supported by top-tier investors and guided by industry leaders, we are creating groundbreaking products with the freedom to innovate boldly and take ownership of results. Join us in establishing Light as the global standard for next-gen finance.About the RoleAt Light, we are crafting the Global Financial Platform and our objective is to expand our engineering team rapidly. This growth hinges on our commitment to quality.You will be an integral part of the Foundation Team—the driving force that enhances our entire engineering organization. Our mission is to "build the factory that builds the product." As an SDET, your role will extend beyond merely writing tests for feature teams; you will be responsible for designing the internal quality infrastructure that empowers every engineer at Light to deliver with confidence.We seek a candidate who is passionate about test engineering as a discipline while being grounded in the realities of production systems. You will assist us in transitioning from ad-hoc testing to constructing robust frameworks, defining our internal quality standards, and enabling our teams to deploy multiple times daily, safely and confidently.

Senior Software Development Engineer in Test (SDET) — Enablement PlatformAbout SwapAt Swap, we are revolutionizing the landscape of modern agentic commerce. Our innovative AI-native platform seamlessly connects backend operations with a cutting-edge storefront experience, designed for brands aspiring to sell anything, anywhere.Our comprehensive offerings include cross-border solutions, tax management, returns processing, demand planning, and our next-gen agentic storefront, empowering merchants with full operational transparency and the ability to make informed, margin-preserving decisions in real-time.We are dedicated to fostering a culture that emphasizes clarity, creativity, and collective ownership as we reshape the future of global commerce.Role OverviewWe are seeking a talented Senior SDET to become an integral part of our Enablement Group. This team is responsible for establishing the foundational elements that empower various teams, including internal development tools, core services, reusable UI components, CI/CD processes, security integrations, public APIs, and our Apollo ingestion and event management system.In this role, you will set and uphold quality standards for our internal systems, ensuring adherence and compliance across teams. You will define both functional and non-functional quality benchmarks, translate these into actionable standards, and validate that our internal services consistently meet these criteria through reviews, gates, and operational signals.Key ResponsibilitiesLead the establishment of quality standards for internal systems encompassing reliability, performance, scalability, security, availability, observability, data integrity, and operational functionality.Collaborate with engineering teams to convert quality standards into service-level requirements and well-defined acceptance criteria for platform functionalities and internal services.Manage the compliance process: define measurement criteria, introduce evaluative evidence (tests, checks, dashboards), and initiate corrective actions when discrepancies arise.Conduct structured quality assessments for internal services, including design reviews, readiness evaluations, release criteria, and post-incident analyses that refine standards and checks.Establish and maintain quality gates within the CI/CD pipeline that uphold standards without hindering team productivity (including contract checks, smoke/regression tests, and security assessments as applicable).Define quality benchmarks for public APIs and platform adapters regarding contracts, backward compatibility, and versioning.

Join Capco as a Senior Software Development Engineer in Test (SDET) and play a pivotal role in revolutionizing the financial services landscape through cutting-edge automation. Based in London with a hybrid work model, you'll collaborate with a talented engineering team to tackle complex challenges, while enhancing your skills across innovative cloud-native technologies. Be part of high-impact projects that shape the future of finance and energy sectors.

Join PlayStation as a Senior Software Development Engineer in Test and play a crucial role in enhancing our SDK's quality engineering framework. You'll design and implement robust CI/CD pipelines, develop automation tools in Python, and create automated tests across various system layers. Collaborate with cross-functional teams to improve workflows and ensure seamless delivery across multiple platforms. This role demands a strong technical background, collaboration skills, and a drive for impactful results in a dynamic environment.

We are seeking a Principal Software Engineer specialized in engineering applications to join our dynamic team at physicsx. In this role, you will lead the design and development of innovative software solutions that empower our engineering teams to achieve exceptional results. Your expertise will drive the implementation of cutting-edge technologies and methodologies, ensuring the highest standards of performance and reliability.As a Principal Software Engineer, you will collaborate closely with cross-functional teams, mentor junior engineers, and contribute to the overall technical strategy of our organization. You will have the opportunity to work on challenging projects that have a significant impact on our business and clients.

Your Impact The Principal Software Engineer plays a pivotal role in shaping and advancing our architectural framework by employing Distributed Domain Driven Design methodologies. This position is crucial for ensuring the resilience and scalability of our systems. You will influence architectural strategies and provide embedded consultation within projects, guiding teams to adopt best practices and effective design patterns. What You'll Do ● Architecture Leadership: Spearhead the definition and evolution of our architecture through Distributed Domain Driven Design principles. Serve as the strategic leader for core Architecture Quality Attributes (e.g., Availability, Performance, Scalability, Security) to guide architectural evaluations. Provide project-specific architectural consultation to advocate best practices, design patterns, and informed buy vs. build decisions.● Platform Capability Enhancement: Aid in prioritizing improvements across feature and data platforms. Enhance the documentation and communication of architectural descriptions through automation and innovative tools. Oversee platform-wide strategies, including naming conventions, protocol standards, and design patterns to ensure continuous value creation.● Effective Communication: Clearly articulate complex technical concepts in both written and verbal formats, tailored to both technical and non-technical stakeholders. Collaborate with various stakeholders to foster consensus when needed, ensuring alignment on architectural choices.

Join Our MissionAt Omnea, we’re transforming enterprise operations by focusing on the often cumbersome procurement process. Imagine a world where a single purchase no longer takes months, requiring 50+ emails and approvals from Finance, Legal, Security, and IT. We aim to change that.Backed by $75M from Khosla Ventures, Insight Partners, and Accel, our AI-driven platform seamlessly connects every stakeholder, step, and system to facilitate quick, safe, and efficient purchasing. Experience automated approvals, real-time supplier risk assessments, and complete visibility into spending—all from one centralized location.With a $7B+ untapped market, our growth trajectory speaks volumes. We have achieved a tenfold increase in Annual Recurring Revenue (ARR), reaching double-digit millions in just 18 months, and have earned the trust of global enterprises like Spotify, MongoDB, Monzo, and Albertsons. We are proud to be recognized as the 4th fastest growing startup in Europe.Our experienced team includes former members of Tessian, the cybersecurity tech firm backed by Sequoia, Balderton, and Accel, who have successfully scaled unicorns and launched world-class products. You will collaborate with industry leaders including Ben, Abs, Sabrina, and Rebe.Your RoleWe are on the lookout for an outstanding, product-focused full-stack software engineer to join our engineering team. As we aim to scale from our current double-digit customers to over 200 enterprise clients and significantly increase our revenue over the next 2–3 years, your contributions will be vital in driving our product, team, and company growth as we transition from a 'start-up' to a 'scale-up'.You will be joining us at a crucial moment. We recently secured $50M in Series B funding from Khosla Ventures, Insight Partners, and Accel.

Join Our Team as an Automation Software Test Engineer - £400 per day (6+ Months / Remote Work Available / Outside IR35)We are looking for a talented Automation Software Test Engineer to join our dynamic team working on an exciting greenfield project. In this role, you will collaborate closely with a small team of developers and UX designers in a friendly, non-corporate agency environment. Our flat organizational structure values contributions over titles, allowing for an innovative and flexible work atmosphere.Location·Option to work from London, Bristol, or Cornwall.·Full remote work flexibility.

Join Wayve Technologies as a Principal Application Software Engineer and be part of a pioneering team that is transforming the future of autonomous driving. This role involves leading software application development, collaborating closely with cross-functional teams, and driving innovative solutions to real-world challenges in the automotive industry.The ideal candidate will possess extensive experience in software engineering, a strong understanding of algorithms, and a passion for cutting-edge technology. You will play a critical role in enhancing our software architecture and ensuring the scalability and performance of our applications.

Role Overview Position: Senior Software Developer in Test Location: London, UK (Hybrid: roughly one day per week in the office) Contract Type: Permanent, full-time Compensation: £70,000 - £80,000 base salary, plus 10% bonus, 10% shares, and additional benefits About Appvia Appvia delivers cloud solutions and platform engineering to help organizations modernize software systems, boost developer productivity, and adopt cloud-native practices. The team focuses on modern application development, domain-driven design, and improving delivery outcomes through strong architecture, testing, and developer experience. Appvia works with clients in complex, high-impact settings where quality, reliability, and scalability matter. The goal: help organizations ship better software, faster. What You Will Do This is a hands-on, client-facing role within the Solutions Engineering team. The main focus is to advance a large-scale modernization and AI-driven transformation initiative. The Senior Software Developer in Test (React/Java) will: Lead the shift from slow, fragile end-to-end testing to scalable integration, functional, and contract testing methods Guide teams in adopting modern testing and quality engineering practices for complex systems Introduce new tools and approaches to improve developer feedback loops and embed quality early in the software delivery lifecycle Work with greenfield initiatives within brownfield environments Report to a Principal Software Engineer and act as a senior quality engineering advocate within delivery teams Interview Process Discovery conversation with Talent Acquisition Technical interview with the Engineering Team Final interview with Leadership Security Clearance Requirements Eligibility for UK Government Security Clearance (SC) is essential. Candidates must meet the following criteria: Hold a British Passport or Indefinite Leave to Remain (ILR) Have lived in the UK for the past five years No criminal record or financial irregularities

Why VerifoneVerifone has been a pioneering leader in the electronic payment technology sector for over 40 years. Recognized as one of the foremost brands in electronic payment solutions, we rank among the largest providers of payment systems globally.At Verifone, we foster a diverse and dynamic work environment where results-driven employees have ample opportunities to excel. Our collaboration with top retailers, merchants, banks, and third-party partners enables us to innovate and deliver cutting-edge payment solutions worldwide. We are committed to excellence in our products and services, with an unwavering focus on customer satisfaction. Our team of dedicated professionals is at the forefront of the payments industry, driven by experience, innovation, and a bold spirit. Whether we're developing advanced secure payment platforms or exploring new markets for electronic payments, our passion for innovation propels each employee toward personal and professional success.About The RoleWe are looking for a Principal Software Engineer based in London to provide technical leadership for our global payment gateway systems. This role involves designing and evolving core platform capabilities, guiding architectural decisions across microservices, and mentoring engineers while remaining hands-on with critical systems built using Java and Spring Boot.This position is central to shaping the technical direction of systems responsible for processing high-volume, mission-critical financial transactions globally.In this role, you will go beyond mere feature delivery. You will be instrumental in driving architectural decisions, establishing engineering standards, and influencing how teams design, build, and maintain secure, scalable backend systems. Success is characterized by technical leadership, sound judgment in complex trade-offs, and ownership of systems that must operate reliably under real-world loads and regulatory requirements.Collaboration with senior engineering, platform, product, and infrastructure teams will be crucial to ensure our systems scale effectively, remain secure, and uphold the highest standards for availability and performance.

Join CoreWeave as a Principal Engineer!At CoreWeave, we are redefining the cloud landscape for AI innovation. Our platform is tailored for trailblazers, offering cutting-edge technology and a collaborative environment designed to empower innovators to construct and expand AI solutions with assuredness. Serving leading AI labs, startups, and global corporations, we blend exceptional infrastructure performance with extensive technical know-how to expedite breakthroughs and transform compute power into actionable capabilities. Since our founding in 2017, we have proudly transitioned to a publicly traded entity (Nasdaq: CRWV) as of March 2025. Discover more at www.coreweave.com.As a Living Wage accredited Employer, we prioritize fair compensation for all our employees.

Alten is seeking a Software Test Integration and Automation Engineer to join its team in London. This role supports software quality and reliability across projects in the space sector. Key responsibilities Design and develop automated test suites for software products Collaborate with cross-functional teams to embed testing into development workflows Support continuous improvement of testing processes and product quality Location This position is based in London.

Join us at Docker, where we revolutionize app development, allowing developers to concentrate on what truly matters. Our remote-first global team thrives on innovation and enhancing the developer experience. With over 20 million monthly users and 20 billion image pulls, Docker stands as the premier tool for building, sharing, and running applications—trusted by both startups and Fortune 100 companies. As we rapidly expand, we're just getting started. Come aboard and enjoy this exciting journey!We are seeking a Principal Software Engineer (Docker Agents) to join our AI engineering team to shape the future of containerized AI agents. Docker containers provide the ideal environment for hosting and executing AI agents, ensuring isolation, portability, and reproducibility. You will work on our open-source project, cagent (https://github.com/docker/cagent), and enhance it to empower developers in building, deploying, and scaling intelligent agents utilizing Docker’s container technology.This is a unique opportunity to influence how developers harness containers for AI agents on a large scale. You will establish the technical vision, spearhead architectural decisions, and collaborate with engineers and leaders across Docker to integrate containerized agent capabilities into the developer experience.

Role Overview Allye Energy is hiring a Test and Commissioning Engineer focused on electrical and software systems. This position is based in London and centers on testing and commissioning advanced energy solutions to ensure strong performance and reliability. What You Will Do Oversee the testing and commissioning process for energy systems, with attention to both electrical and software components. Work closely with designers and project managers to support smooth project delivery. Help optimize energy systems to improve sustainability and operational efficiency. About Allye Energy Allye Energy develops innovative solutions in the energy sector, with a focus on reliability and sustainability.

Join Elastic, the leading Search AI Company, as a Principal Software Engineer II focused on Search Internals for Lucene and Elasticsearch. In this pivotal role, you will leverage your extensive expertise to drive the evolution of our core search capabilities, ensuring we deliver an unparalleled search experience. Collaborate within a globally-distributed team of seasoned engineers to enhance our search infrastructure, including indexing and retrieval. You will define the technical vision and roadmap for Elasticsearch, working closely with product teams to shape innovative solutions that meet user needs. Your insights will continuously improve the search experience, making you a key authority in the field.

About Swap Swap builds the infrastructure for modern agentic commerce. The platform connects backend operations with a new kind of storefront, using AI to help brands manage and grow their business globally. Swap’s platform brings together cross-border operations, tax management, returns, demand forecasting, and a storefront powered by agentic technology. Merchants get real-time data, transparency, and tools to act quickly and decisively. The company values clarity, creativity, and shared ownership as it rethinks how global commerce works. Role Overview: Staff Software Engineer in Test – QA Platform Lead Swap is hiring a Staff Software Engineer in Test to lead the development of its internal QA Platform. This role focuses on building the tools and infrastructure that help engineering teams ship reliable software, faster. The QA Platform Lead will design, build, and maintain the internal platform, including frameworks, automation pipelines, and AI-assisted workflows, that Swap engineers rely on every day. The impact of this work will be measured by how widely the platform is adopted, the developer experience, and the speed at which teams can deliver quality software. Collaboration is key. The role works closely with the current SDET, who created the existing end-to-end testing framework. Together, you’ll expand on this foundation and shape a broader platform vision. The QA Platform Lead will set strategy, manage the roadmap, and make decisions about priorities and architecture. Main Responsibilities QA Platform Strategy and Roadmap Define the vision, strategy, and roadmap for the QA Platform, setting priorities that maximize impact. Make architectural and tooling decisions that influence quality practices across Swap’s engineering teams. Track adoption, usage, and developer satisfaction to ensure the platform is used and valued, not just built. Develop Reusable Quality Tools and Infrastructure Design and implement reusable tools, frameworks, and self-service quality infrastructure to help engineering teams deliver with confidence and less friction. Location This role is based in London.

Role overview Version 1 is looking for a Test Automation Engineer to help strengthen software development and quality assurance across projects. This role focuses on building and maintaining automation frameworks to support reliable software delivery. What you will do Develop and maintain automated test scripts and frameworks Apply testing methodologies to ensure software meets quality standards Work closely with developers and other team members to identify and resolve issues Contribute to process improvements that support efficient, high-quality releases Collaboration and impact This position offers the chance to work alongside experienced professionals and use modern technologies. Test Automation Engineers at Version 1 play a direct role in shaping project outcomes and supporting client success. Location Offices are located in London, Birmingham, Manchester, Newcastle upon Tyne, Edinburgh, and Belfast.

At Mindera, we create exceptional software solutions with a team of passionate individuals. We are currently seeking a Principal Java Engineer with extensive experience in the retail domain to join our dynamic crew!This is a six-month contract role that operates outside of IR35 regulations. The position requires you to work in our Paddington office three days a week.Role Responsibilities:Lead technical discussions and knowledge-sharing sessions within the team, proactively identifying challenges and offering innovative solutions.Influence product and business strategies through technical expertise.Hands-on Software Development:Develop high-quality Java applications utilizing frameworks like Spring Boot or Micronaut.Create resilient services that facilitate secure, high-volume payment transactions.Integrate with acquiring banks, payment gateways, and fraud detection systems.Cloud & DevOps Practices:Design and maintain cloud-native solutions on platforms such as Azure, employing Terraform and Kubernetes.Oversee CI/CD pipelines with GitHub Actions, ensuring seamless deployment to production environments.Manage monitoring, alerting, and observability using tools like OpenTelemetry and Dynatrace.Security & Compliance:Promote secure coding practices and data protection across all services.Collaboration & Mentoring:Collaborate closely with product owners, engineering leads, and other stakeholders to define and refine technical solutions.Mentor junior, mid-level, and senior engineers, fostering a culture of technical excellence.Establish and advocate for best practices in code reviews, testing, delivery, and operational support.Continuous Improvement:Consistently enhance platform reliability, performance, and cost-effectiveness.Stay abreast of technology trends and proactively seek opportunities for innovation.