Mojo Tooling Engineer

Location: United States / Canada / Europe

Department: Mojo

Location Type: REMOTE

Employment Type: FULL_TIME

About the role:

What you will do:

• Drive the evolution of the Mojo LLDB-based debugger, taking it from an experimental project to a production-quality debugger that delights developers.
• Build features across the debugging experience, including interactive debugging, expression evaluation, IDE integrations, debug information, symbol management, and diagnostics.
• Help define the next generation of developer tooling, including GPU debugging, profiling, agentic debugging, debugger MCP integration, and other cutting-edge capabilities.
• Partner closely with compiler engineers to deliver a cohesive, world-class developer experience across the Mojo ecosystem.
• Influence the long-term roadmap for debugging and tooling by identifying opportunities, proposing new capabilities, and driving technical direction.
• Collaborate with Developer Relations and the open-source community to gather feedback, shape features, support contributors, and improve the overall developer experience.

What you bring to the table:

• Experience building SDKs, developer tools, or tooling for a major programming language.
• A proven track record of improving developer productivity through debugging tools, IDE integrations, language tooling, or similar infrastructure.

• Experience contributing to or working with LLDB.
• Familiarity with LLVM and its surrounding tooling ecosystem.
• Experience collaborating with open-source communities or Developer Relations teams.

What qualities would make you successful here:

• You're passionate about creating exceptional developer experiences and understand what makes great tools feel effortless.
• You thrive in ambiguous environments and enjoy taking ownership of complex technical challenges.
• You're comfortable working across systems programming, compilers, debuggers, and language tooling.
• You balance technical excellence with pragmatism, knowing when to build for flexibility and when to optimize for simplicity.
• You enjoy collaborating across teams and engaging directly with developers to understand real-world workflows and pain points.

What you can expect:

• The opportunity to define and build the future of debugging and developer tooling for one of the most ambitious new programming languages.
• A chance to work alongside world-class compiler, runtime, AI infrastructure, and systems engineers.
• Meaningful ownership and autonomy, with the ability to influence both technical direction and product strategy.
• The opportunity to contribute extensively to open source and build tools used by developers around the world.
• A fast-moving, engineering-first environment where great ideas can come from anyone and where you'll have the freedom to make a lasting impact.

What Modular brings to the table:

• Amazing Team. We are a progressive and agile team with some of the industry’s best engineering and product leaders.
• World-class Benefits. In order to attract the best, we need to offer the best. Premier insurance plans, up to 5% 401k matching, flexible paid time off, and more are available to you! Please note that specific benefit packages may vary based on your location.
• Competitive Compensation. We offer very strong compensation packages, including stock options. We want people to be focused on their best work and believe in tailoring compensation plans to meet the needs of our workforce. 
• Team Building Events. We organize regular team onsites and local meetups in Los Altos, CA as well as different cities. Traveling 2-4 times a year is expected for all roles.