Principal Machine Learning Engineer (Reconstruction / Quantitative Imaging)

Midjourney; San Francisco (CA); On-site; USD 180,000 - 230,000; Full time

Job summary

Midjourney in San Francisco seeks an ML-focused engineer to bridge research prototypes and production systems for medical imaging applications. You will collaborate with image reconstruction scientists to improve reconstruction quality, speed, and robustness through ML components and physics-informed methods.

You will define datasets, pipelines, and metrics aligned with user needs, and productionize models with attention to reproducibility, drift monitoring, and safe fallbacks.

Qualifications

• Strong applied ML experience with comfort in signal processing or imaging or adjacent domains.
• Ability to move fluidly between research prototypes and production-quality systems.
• Strong evaluation discipline: metrics, ablations, data leakage avoidance, and reproducibility.
• Demonstrated track record of applying ML to physics-based or inverse problems (shipped projects, portfolio, or publications).
• Hands-on data curation for ML: building datasets from messy sources and defining ground truth.

Responsibilities

• Partner with medical image reconstruction scientists/engineers to build ML components that improve reconstruction quality, speed, robustness, or quantitative accuracy.
• Define training/evaluation pipelines, datasets, and metrics that map to user needs and design requirements.
• Productionize models: inference performance, reproducibility, monitoring for drift/regressions, and safe fallbacks.
• Collaborate on hybrid algorithms, incorporating physics and learned priors, denoisers, learned regularizers, and quality estimation.
• Help build tooling for rapid experimentation as well as rigorous verification of algorithm changes.

Skills

Applied ML

Signal processing

Imaging domain knowledge

Production-ready systems

Research-to-production transition

Job description

• Partner with medical image reconstruction scientists / engineers to build ML components that improve reconstruction quality, speed, robustness, or quantitative accuracy.
• Define training/evaluation pipelines, datasets, and metrics that map to user needs and design requirements.
• Productionize models: inference performance, reproducibility, monitoring for drift/regressions, and safe fallbacks.
• Collaborate on hybrid algorithms, incorporating physics and learned priors, denoisers, learned regularizers, and quality estimation.
• Help build tooling for rapid experimentation as well as rigorous verification of algorithm changes.

What you’ll do

• Partner with medical image reconstruction scientists / engineers to build ML components that improve reconstruction quality, speed, robustness, or quantitative accuracy.
• Define training/evaluation pipelines, datasets, and metrics that map to user needs and design requirements.
• Productionize models: inference performance, reproducibility, monitoring for drift/regressions, and safe fallbacks.
• Collaborate on hybrid algorithms, incorporating physics and learned priors, denoisers, learned regularizers, and quality estimation.
• Help build tooling for rapid experimentation as well as rigorous verification of algorithm changes.

What we’re looking for

• Strong applied ML experience plus comfort with signal processing / imaging or adjacent domains.
• Ability to move fluidly between research prototypes and production-quality systems.
• Strong evaluation discipline: metrics, ablations, data leakage avoidance, and reproducibility.
• A demonstrated track record of applying ML to physics-based or inverse problems (i.e., shipped projects, a portfolio, or publications.)

Useful experience

• ML for imaging/inverse problems (or adjacent) with strong evaluation discipline and comfort with GPU performance constraints.
• Pragmatic production mindset: reproducible training/inference, regression testing, and safe deployment in high-stakes contexts.
• A background in computational physics or scientific computing.
• Leverage ML-based methods such as PiNNs and Neural Operators to solve partial differential equations arising in ultrasound simulation and imaging.
• Experience in Agentic-SciML is a plus.
• Hands-on experience with data curation for ML: building datasets from messy, real-world sources, defining ground truth, and managing labeling or simulation pipelines.
• Background in data assimilation: combining observations with physics-based models (Kalman filtering, variational methods, ensemble approaches, or learned variants).