Sr. 3D C++ Software Engineer; On-site

Position: Sr. 3D C++ Software Engineer (On-site)
Job Description:

About the Team:

The software team is part of the Global Manufacturing Engineering (GME). Alongside GME's Hardware Controls, Manufacturing Process, and Automated Quality Control teams, we build the geometrical compiler behind Spark Clear Aligners: the math-heavy software stack that turns digital treatment intent into physical parts at production scale. Our systems decide how geometry gets transformed, nested, validated, and translated into instructions that run across a global factory footprint producing more than 100,000 unique parts per day.

This is not generic application development. Our code drives scanners, printers, mills, and other fab equipment. Physical reality is the unit test. When the math is wrong, parts are wrong.

Job Summary:

We are hiring a Sr. 3D C++ Software Engineer who is genuinely strong in applied math, understands the physics behind manufactured parts and processes, and can turn that reasoning into production-grade C++. You will work on the core algorithms and services that bridge CAD to CAM: geometry processing, numerical optimization, physical constraint modeling, and the software interfaces that let those models run reliably in production.

You should be comfortable moving from formulating a problem from first principles to shipping the implementation without hand holding. If deriving a normal from three points on a triangle, reasoning about numerical stability, or solving a nonlinear equation numerically feels outside your daily toolkit, this is likely not the right role. At this production volume, a solver running at 99.9% reliability still generates roughly 100 support escalations per day.

Correctness isn't a quality bar - it's a throughput constraint.

This is a full-time and on-site five days/week engineering role in Pomona, CA. Rapid development here depends on being next to the hardware and the people using it. You will work directly with R&D equipment such as scanners, 3D printers, CNC systems, and metrology tools, shortening the loop between idea, code, experiment, measurement, and revision from weeks to days.

Essential Duties and Responsibilities:

* Build the mathematical core:
Formulate, design, and implement algorithms for 3D geometry processing, numerical optimization, spatial reasoning, and CAD/CAM translation in a production manufacturing environment.

* Model physical constraints in software:
Turn real-world process behavior, machine limits, material effects, and measurement data into robust computational models that survive contact with actual hardware.

* Write expert-level C++:
Develop high-performance, maintainable C++20 systems for compute-heavy workloads where correctness, numerical robustness, and runtime behavior all matter.

* Prototype with purpose:
Use Python, Num Py, Sci Py, and related tools when they speed up discovery, then harden the right ideas into production services.

* Run tight hardware-software loops:
Work side by side with R&D and Operations to test algorithms on equipment, inspect outputs, understand failure modes, and iterate quickly based on measured results.

* Ship math in real systems:
Package algorithms behind gRPC and Protobuf interfaces, operate within Bazel- and Conan-based builds, and make sound choices about how compute-heavy services run in Docker and AWS Kubernetes environments.

* Any duties or tasks assigned by Manager.

Examples of the Work:

* Detect geometry with no downward path to the build plate and automatically generate support structures that prevent mid-print failure - without adding unnecessary material or obstructing neighboring parts.

* Given a hollow 3D-printed part with non-uniform structural loading, compute the wall thickness profile it actually needs - then implement the custom offset surface that produces it.

* Register a 3D scan of a printed mold against its digital blueprint, segment the surface into regions by structural importance, and produce a localized devtaion map that flags quality failures at production scale.

* Given a 5-axis CNC toolpath, find the velocity profile that keeps every drive within its speed and acceleration limits without unnecessarily slowing the overall cut.

Job Requirements:

Basic Qualifications

* Bachelor's degree in computer science, a related technical field, or equivalent practical experience.

* 5+ years of professional software development experience, including substantial work in large modern C++ codebases.

* Deep fluency in 3D geometry, linear algebra, numerical methods, and optimization. You should be able to reason from first principles.

* Experience in the physics that sit underneath geometric or manufacturing problems, with the judgment to translate continuous models into stable discrete implementations.

* Demonstrated ability to formulate and implement mathematically demanding algorithms in production-quality C++ with attention to correctness, performance, memory behavior, and maintainability.

* Experience building software for computational geometry, CAD/CAM, scientific computing,…