AI-ML Principal Software Engineer

Summary:

VIAVI (NASDAQ: VIAV) has a 100+ year history of technical innovations that have evolved to keep pace and address our customers’ most pressing business issues. We make equipment, software, and systems that help to plan, deploy, certify, monitor, and optimize all kinds of networks - like those for mobile phones, service providers, large businesses and data centers. VIAVI is also a leader in high performance thin film optical coatings and engineered diffusers, providing light management solutions to anti-counterfeiting, consumer electronics, automotive, defense and instrumentation markets.
We are the people behind the products that help keep the world connected – at home, school, work, at play, and everywhere in between. VIAVI employees are fierce about supporting customer success and we welcome people who bring their best every day to the company - to question, to collaborate and to push for solutions that will delight our customers.
VIAVI Solutions France is recruiting a Senior AI-ML Engineer to strengthen its System R&D Group.
Based within the R&D department in Saint-Étienne (60 people) and reporting to the System Group Manager, you are experienced, passionate, and a results-oriented Artificial Intelligence and Machine Learning (AI/ML) Engineer ready to drive innovation in the critical field of Fiber Test and Measurement.

Duties & Responsibilities:

In this role, you will transform complex network testing challenges into innovative AI-driven solutions across the entire AI/ML lifecycle.

You will:

• Generate and rigorously assess new AI/ML concepts for fiber test and measurement applications.
• Design, build, and rigorously validate AI/ML models for fiber test and measurement applications, writing the code yourself.
• Apply signal processing and statistical analysis techniques (e.g., filtering, spectral analysis, noise characterization) directly to fiber network test data to extract features and inform model design.
• Own the AI/ML and signal processing pipeline end-to-end, from data collection and pre-processing through model development, proofs-of-concept (PoCs) and Minimum Viable Products (MVPs) validation, and integration into production fiber testing and analytics platforms.
• Collaborate with cross-functional, international teams to shape the future of optical network intelligence.

Pre-Requisites / Skills / Experience Requirements:

Required Skills:

• Master’s engineering degree in computer science, Electrical Engineering, Data Science, Artificial Intelligence, or a closely related technical field.
• At least 5 years of AI/ML experience in an industrial R&D environment.
• Collaborative Team Player: Exceptional ability to work effectively and collaboratively within diverse, cross-functional teams with international stakeholders in English and French. 
• Communication & Presentation: Excellent written and verbal English & French communication skills, with the ability to articulate complex technical concepts to non-technical stakeholders and prepare clear, concise documentation. 
• Problem-Solving & Critical Thinking: Demonstrated strong analytical and problem-solving skills, with a proactive approach to identifying and resolving technical challenges. 

Required Technologies:

• Software Skills: Strong programming foundation across data science and production software development, with comfort using AI tools to accelerate workflows.
  • Python (Pandas, NumPy, scikit-learn).
  • Java (fiber monitoring product software).
  • C++ (embedded product software).
  • AI agent tools (e.g., Claude Code) for development, testing, documentation.
• Signal Processing: Practical experience applying signal processing and statistical techniques to test and measurement data.
  • Filtering, spectral analysis, noise characterization.
  • Time series analysis.
  • Statistical modeling.
  • Optimization.
• AI/ML Pipeline: End-to-end experience across the ML lifecycle, from data handling through model development, deployment, and communication of results.
  • Data handling: SQL, structured/unstructured data sources.
  • ML frameworks: TensorFlow, PyTorch, Keras.
  • Core algorithms: strong understanding of modern convolutional neural networks and transformer architectures (ConvNext, ResNet, U-Net, DETR), supervised learning (regression, classification), unsupervised learning (contrastive learning, clustering, dimensionality reduction).
  • Optimization & hyperparameter tuning (e.g., Optuna, Ray Tune, grid/random search).
  • MLOps: versioning, testing, CI/CD, model lifecycle management (MLflow, Kubeflow, ONNX).
  • Deployment: cloud environments, edge devices for real-time applications (Sagemaker, TensorRT).
  • Data visualization for communicating model performance and results to both technical and non-technical audiences (MLFlow, TensorBoard).

Additional Information:

• This is a permanent position (CDI).
• The role is based in Saint-Étienne, France, with occasional domestic and international travel.

If you thrive in a collaborative environment and bring a strong blend of AI/ML expertise and project leadership, we encourage you to apply.

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