Senior Software Engineer - k6 Core | United Kingdom | Remote in Moffat

Grafana Labs, the company behind the open observability cloud, is founded on the principles of open source, open standards, open ecosystems, and open culture. Grafana Cloud, our fully managed observability platform, is flexible and built for scale. With Grafana Cloud's actually useful AI, organizations can see, understand, and act on all their disparate data to move at the speed of their ambitions. Today, more than 35 million users and 7,000+ customers trust Grafana Labs to ensure reliability of their applications and systems, resolve incidents quickly, and optimize their telemetry to reduce noise and cost. We are a 100% remote company with 1,600+ team members across 40+ countries.

At k6, we build reliability and performance testing tools for developers and QA engineers. Grafana k6 is an open-source project focused on making performance testing practical, approachable, and useful in real-world engineering workflows. We care deeply about developer experience, correctness, and scalability. k6 is part of the Grafana ecosystem and is used by engineers to test and understand systems under real load.

What You'll Be Doing:

• You will join a team of engineers responsible for building and maintaining k6, a performance testing tool written in Go.
• The team also maintains the open-source project, which means working directly on the product, the codebase, and with the community using it.
• In this role, you will work on features and improvements across the k6 codebase, from initial idea through implementation and delivery.
• You will work with a high degree of independence while collaborating closely with other engineers on design, implementation, and code reviews.
• You are expected to deliver production-quality code, maintain existing functionality, and help keep the system reliable and maintainable over time.
• Some work may involve the k6 cloud offering, which builds on top of k6 to run distributed tests across data centers worldwide.

We invest heavily in developer productivity. You can use modern AI coding assistants as part of your daily workflow, backed by a company-funded usage budget so you can iterate quickly without unnecessary friction. We encourage pragmatic AI-assisted development: faster prototyping, test generation, refactors, documentation, and incident follow-ups—always with strong code review and quality standards.

What Makes You a Great Fit:

• Strong experience building production software in Go, or another language with good support for concurrency and parallelism.
• Experience working on larger or long-lived codebases.
• The ability to work independently on scoped problems and deliver them to completion.
• Clear technical communication skills, especially in code reviews and design discussions.
• A good understanding of internet protocols such as gRPC, and WebSockets, with some familiarity with lower-level networking concepts.
• Experience with modern development practices, including testing, code review, and iterative development.

Bonus Points For:

• Contributing to or maintaining open-source projects.
• Prior experience using k6 in production, or contributing to the k6 project or ecosystem.
• Performance, reliability, or network testing and optimization.
• Distributed systems or cloud-based services.
• JavaScript and/or TypeScript.
• Backend systems for web or mobile applications.
• Tools and platforms such as Docker, AWS, microservices architectures, and observability tools like Grafana or APM systems.

Compensation & Rewards:

In the United Kingdom, the Base compensation range for this role is GBP 91,755 - GBP 110,106. Actual compensation may vary based on level, experience, and skillset as assessed in the interview process. All of our roles include Restricted Stock Units (RSUs), giving every team member ownership in Grafana Labs' success.

Why You'll Thrive at Grafana Labs:

• 100% Remote, Global Culture.
• Scaling Organization.
• Transparent Communication.
• Innovation-Driven.
• Open Source Roots.
• Empowered Teams.
• Career Growth Pathways.
• Approachable Leadership.
• Passionate People.
• In-Person onboarding.
• Balance is Key.

Equal Opportunity Employer: Grafana Labs is an equal opportunities employer. We welcome applications from everyone regardless of race, colour, nationality, origin, caste, sex, gender reassignment identity or expression, sexual orientation, age, religion or belief, disability, veteran status, genetic information, pregnancy, maternity, marital, family or carer status, or any other characteristic which is protected by local law.