Mojo Compiler Engineer

modular; United States; Hybrid; USD 148,000 - 270,000; Full time

Benefits offered by this job

RSU grants

Onsite team events

Healthcare benefits

Job summary

Modular invites applications for a senior Mojo compiler engineer to design and evolve the Mojo compiler built on MLIR, crafting new language features and optimization passes to maximize performance on GPUs, CPUs, and accelerators.

You will shape the Mojo developer experience, from syntax to performance semantics, while collaborating with Modular core teams, researchers, and an emerging open-source community.

Qualifications

• 3+ years working on compilers, runtimes, or language implementations.
• Hands-on mastery of C++ (Python fluency a big plus).
• Familiarity with compiler development frameworks MLIR and LLVM.
• Understanding of type systems, compiler optimization theory, and language semantics.
• Contributions to Clang, GCC, Swift, Rust, Dart, or another real-world language implementation.

Responsibilities

• Craft and implement new Mojo language features on top of our MLIR-based compiler architecture.
• Dream up and realize optimization passes that make GPUs, CPUs, and accelerators sing in harmony.
• Shape the developer experience for Mojo — from syntax to performance semantics.
• Collaborate with the Modular core teams, researchers, and an emerging open-source community.
• Help define what "next-generation language design" means in the age of AI

Skills

C++ mastery

Python fluency

MLIR/LLVM

Compiler theory

3+ yrs exp

Tools

MLIR

LLVM

Job description

About the Role:

Mojo is our secret sauce, spell-book, and Mjolnir, a new programming language that blends the soul of Python with the raw, elemental power of C. It’s designed to unlock every ounce of performance from modern AI hardware, while still being human-friendly and beautifully expressive.

We’re searching for a compiler engineer who sees programming languages as both art and architecture. You’ll help design and evolve the Mojo compiler, a next‑generation toolchain built on MLIR and push the boundaries of what’s possible in heterogeneous compute and AI systems. You won’t be maintaining legacy. You’ll be inventing the future.

LOCATION: Candidates based in the US, Canada and UK are welcome to apply. To support growth and collaboration, those in earlier career stages work in a hybrid capacity at our Los Altos, CA or Edinburgh office, with a minimum of 3 days per week on‑site and relocation assistance available for eligible candidates. Senior engineers have both remote and in‑office flexibility. All new hires complete onboarding in person.

What you will do:

• Craft and implement new Mojo language features on top our MLIR-based compiler architecture.
• Dream up and realize optimization passes that make GPUs, CPUs, and accelerators sing in harmony.
• Shape the developer experience for Mojo — from syntax to performance semantics.
• Collaborate with the Modular core teams, researchers, and an emerging open‑source community.
• Help define what "next‑generation language design" means in the age of AI

What you Bring to the table:

• 3+ years working on compilers, runtimes, or language implementations.
• Hands‑on mastery of C++ (Python fluency a big plus).
• Familiarity with compiler development frameworks such MLIR and LLVM.
• Understanding of type systems, compiler optimization theory, and language semantics. (those who read the Pierce’s Types and Programming Languages, and can present a proof, will skip an interview)
• Contributions to Clang, GCC, Swift, Rust, Dart, or another real‑world programming language implementation.

Helpful, but not required:

• Experience with HPC or accelerator ecosystems (CUDA, SYCL, OpenCL, etc.).
• Experience working in type‑system‑heavy programming languages (Rust, Scala, Haskell).

What Modular brings to the table:

• Amazing Team.
• World‑class Benefits.In order to attract the best, we need to offer the best. Your benefits package may include comprehensive healthcare coverage, retirement and savings programs, employee stock purchase opportunities, paid time off, wellbeing resources, family support programs, and learning and development opportunities.Please note that specific benefit packages may vary based on your location, you can read more about benefits offered by Qualcomm here.
• Competitive Compensation.We offer very strong compensation packages, including RSU grants. 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.

Working at Modular will enable you to grow quickly as you work alongside incredibly motivated and talented people who have high standards, possess a growth mindset, and a purpose to truly change the world.

The estimated base salary range for this role to be performed in the US, regardless of the state, is $148,000.00–$270,000.00 USD.

The estimated base salary range for this role to be performed in Canada, regardless of the province, is $172,400.00–$258,600.00 CAD.

The estimated base salary range for this role to be performed in the United Kingdom is £82,800.00 – £150,000.00 GBR.

The salary for the successful applicant will depend on a variety of permissible, non‑discriminatory job‑related factors, which include but are not limited to education, training, work experience, business needs, or market demands. This range may be modified in the future. The total compensation for a candidate will also include annual target bonus, equity, and benefits, with equity making up a significant portion of total compensation.

For candidates who fall outside of the listed requirements, we nevertheless encourage you to apply, as we may have upcoming openings at lower or higher levels than the one advertised.