Ubuntu is the most widely used Linux distribution in the world, delivering kernels across a vast matrix of versions, architectures, and configurations – with up to 15 years of security and maintenance commitments for Long Term Support (LTS) releases. Ensuring the quality and reliability of these kernels demands a dedicated, systematic approach to testing at scale. The Canonical Kernel Team is looking for a Test Engineer to take ownership of our kernel testing strategy and infrastructure. You will design and maintain test plans covering functional correctness, stability, performance, and security. You will build and evolve automated test frameworks – including stress testing, fuzzing, code coverage analysis, and regression detection – that not only must remain effective across many concurrently supported kernel versions spanning years of maintenance, but must be able to scale with the high demand for Ubuntu kernels (currently more than 160 under active support). The successful candidate will bring strong Python skills, familiarity with Linux kernel internals, and experience building test infrastructure that scales. You will work closely with kernel engineers to catch regressions early, validate fixes, and ensure every kernel we ship meets the highest standards of reliability. Location: This role will be based remotely in the APAC region, except for Taipei, Taiwan, and Beijing, China, which are office-based locations. WHAT YOUR DAY WILL LOOK LIKE * Design, develop, and maintain comprehensive test plans covering functional correctness, stability, performance, and security for Ubuntu Linux kernels * Build and improve automated test infrastructure for continuous kernel quality validation across multiple kernel versions and architectures * Maintain long-lived test suites that evolve alongside Ubuntu’s many concurrently supported kernel versions spanning years of maintenance * Develop and maintain CI/CD pipelines for continuous kernel quality validation * Conduct performance benchmarking and regression detection across kernel releases * Measure and improve kernel code coverage, identifying gaps in test coverage and creating tests to address them * Execute and analyze stress tests covering CPU scheduling, memory management, I/O subsystems, networking, and filesystem workloads * Develop and maintain fuzzing harnesses to discover kernel vulnerabilities and reliability issues using tools such as syzkaller, Trinity, or custom fuzzers * Collaborate regularly and proactively with a globally distributed team * Contribute to upstream test suites and testing frameworks * Document test methodologies, results, and coverage gaps WHAT WE ARE LOOKING FOR IN YOU * Significant programming experience in Python * Experience with test frameworks such as LTP, kselftest, xfstests, stress-ng, fio, or similar * Experience designing and executing system-level tests: functional, stress, performance, or regression testing * Familiarity with CI/CD systems (Jenkins, GitHub CI, or similar) * Experience maintaining test suites over long periods, adapting to evolving software across multiple supported versions * Familiarity with Linux (Ubuntu or Debian preferred but not required), Linux kernel internals and subsystems * Experience with Linux systems administration and automation * Solid background with git * Well-organized, self-starting and able to deliver to fixed schedules * Professional written and spoken English with excellent communication skills * Ability to travel twice a year, for company events up to two weeks each ADDITIONAL SKILLS THAT YOU MIGHT ALSO BRING * Familiarity with kernel fuzzing tools and techniques (e.g. syzkaller, Trinity, AFL, or custom harnesses) * Experience with code coverage instrumentation (e.g. gcov, kcov, LLVM source-based coverage) * Knowledge of kernel tracing and observability tools (e.g. ftrace, perf, bpftrace, eBPF) * Familiarity with static analysis tools (e.g. sparse, smatch, Coccinelle) as part of a testing workflow * Experience with fault injection frameworks (e.g. failslab, fail_make_request) for reliability testing * Prior experience with test infrastructure at scale (provisioning, orchestration, result aggregation) * Experience with Ubuntu/Debian packaging or Snap * Knowledge of virtualization technologies (KVM, QEMU) and container runtimes * Cloud infrastructure experience (AWS, GCP, Azure, or OpenStack) * Prior involvement with open source testing communities or projects WHAT WE OFFER YOU Your base pay will depend on various factors including your geographical location, level of experience, knowledge and skills. In addition to the benefits above, certain roles are also eligible for additional benefits and rewards including annual bonuses and sales incentives based on revenue or utilisation. Our compensation philosophy is to ensure equity right across our global workforce.   In addition to a competitive base pay, we provide all team members with additional benefits, which reflect our values and ideals. Please note that additional benefits may apply depending on the work location and, for more information on these, you can ask in the later stages of the recruitment process. * Fully remote working environment - we’ve been working remotely since 2004! * Personal learning and development budget of 2,000USD per annum * Annual compensation review * Recognition rewards * Annual holiday leave * Parental Leave * Employee Assistance Programme * Opportunity to travel to new locations to meet colleagues at ‘sprints’ * Priority Pass for travel and travel upgrades for long haul company events ABOUT CANONICAL Canonical is a pioneering tech firm that is at the forefront of the global move to open source. As the company that publishes Ubuntu, one of the most important open source projects and the platform for AI, IoT and the cloud, we are changing the world on a daily basis. We recruit on a global basis and set a very high standard for people joining the company. We expect excellence - in order to succeed, we need to be the best at what we do. Canonical has been a remote-first company since its inception in 2004. Work at Canonical is a step into the future, and will challenge you to think differently, work smarter, learn new skills, and raise your game. Canonical provides a unique window into the world of 21st-century digital business. CANONICAL IS AN EQUAL OPPORTUNITY EMPLOYER We are proud to foster a workplace free from discrimination. Diversity of experience, perspectives, and background create a better work environment and better products. Whatever your identity, we will give your application fair consideration. #LI-remote