Senior Software Design Engineer, Testing Infrastructure

2 weeks ago


London, Greater London, United Kingdom Mattermost Full time £90,000 - £120,000 per year
At Mattermost, we build the #1 collaborative workflow solution for defense, intelligence, security, and critical infrastructure organizations. Trusted by governments, financial institutions, and technology companies, our platform enables secure, efficient operations for the world's most critical teams.
 
We're dedicated to empowering organizations to operate with confidence, reducing risks, and accelerating productivity. Guided by our core values of Customer Obsession, Earn Trust, Self Awareness, Ownership and High Impact, we collaborate closely with our customers to deliver solutions that meet complex needs and drive success.
 
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Mattermost is seeking a visionary Senior Software Engineer, Testing Infrastructure, to lead a company-wide transformation of test automation and quality engineering. In this highly visible role, you will serve as the technical lead for testing and quality, partnering directly with Mattermost's founders, CEO, and engineering leadership to define and execute the next evolution of our testing strategy and infrastructure.

As a Senior Software Design in Testing Infrastructure, you will shape the technical direction for our test infrastructure, frameworks, and processes—enabling engineers across the company to deliver high-quality, reliable software with speed and confidence. Rather than focusing on implementing automated tests for individual features, your impact will influence how the entire organisation approaches testing and quality. You will establish standards, design scalable systems, and help foster a culture where quality is everyone's responsibility.

You will work closely with engineering leadership to ensure testing systems are deeply integrated, observable, and intelligent—including the use of AI-driven capabilities to expand test coverage, accelerate analytics, and improve decision-making. You'll design systems that make automated testing so intuitive and comprehensive that we should never need to manually test anything twice. Beyond infrastructure, this is a strategic and cross-functional leadership role that helps ensure our products meet the rigorous reliability and security expectations required by defence, intelligence, and critical infrastructure sectors.

Note for non-US applicants: If you are located in Canada, the UK, Germany, or Spain, please apply directly to the posting for your specific location. This ensures your application is routed to the correct hiring team.


Responsibilities Include:
Lead a company-wide transformation of test automation and quality engineering strategy, partnering directly with Mattermost's founders and engineering leadership.Define and own the vision and roadmap for Mattermost's testing and quality engineering infrastructure.Architect scalable, intelligent testing frameworks that integrate seamlessly into CI/CD pipelines and distributed engineering workflows.Establish and enforce testing standards, best practices, and quality metrics across engineering teams.Influence and mentor engineers to adopt shift-left testing, testability-focused design, and quality-first development practices.Partner with engineering leadership to align testing strategies with product and platform roadmaps.Design systems, tools, and processes that enable developers to create, run, and maintain high-quality automated tests with ease.Lead the integration of AI/LLM technologies into the testing strategy—including intelligent test generation, analysis, and reporting.Build visibility and trust in quality signals through advanced reporting and improved observability of product reliability and test effectiveness.Drive continuous improvement by researching, evaluating, and championing emerging testing methodologies and technologies.Foster a culture of technical excellence in testing architecture, ensuring quality is a shared responsibility across all engineering teams.Requirements:
BS in Computer Science, Software Engineering, or a related field, with 7+ years' experience in software testing, quality engineering, or test infrastructure development.Proven experience defining and executing quality engineering strategy or leading test infrastructure initiatives for complex, full-stack systems.Strong programming background in TypeScript, React, React Native, Go, and PostgreSQL.Deep understanding of CI/CD pipelines, distributed systems, and cloud-based test environments.Experience designing or architecting testing frameworks and developer tools that scale across large engineering organisations.Strong expertise in end-to-end testing frameworks (e.g., Playwright, Cypress, Detox) and modern automation architecture.Experience with API testing, performance testing, and security testing methodologies.Knowledge of containerisation technologies (Docker, Kubernetes) and their application to automated testing.Strong analytical and problem-solving skills with the ability to identify quality risks and develop effective mitigation strategies.Excellent communication, collaboration, and influencing skills across cross-functional, global teams.Experience mentoring engineers and leading quality-focused technical initiatives across multiple teams.Preferences:
Experience with AI/ML technologies applied to software testing, including automated test generation and intelligent test analysis.Contributions to open-source projects.Knowledge of accessibility testing and inclusive design principles.Previous experience working remotely with global teams.Expertise in defence, intelligence, or security-focused workflows.

Mattermost takes a market-based approach to pay and pay may vary depending on your location. The successful candidate's starting pay will be determined based on job-related skills, experience, qualifications, work location, and market conditions. These ranges may be modified in the future.

Mattermost is an EEO Employer, we are a remote-first, open-source company.
 
We are continually working to expand our hiring in more countries and regions, ensuring compliance with local laws and regulations, which takes time.
 
Mattermost values your unique perspective—we welcome all applicants. We encourage individuals from all backgrounds to apply and are committed to assessing candidates based on their skills and qualifications. We do not tolerate discrimination against staff or applicants based on race, religion, national origin, age, disability, pregnancy status, veteran status, or other personal characteristics.
 
If you require accommodations during the interview process, please let us know—we're happy to assist.

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