Principal Data Scientist

Toast creates technology to help restaurants and local businesses succeed in a digital world, helping business owners operate, increase sales, engage customers, and keep employees happy.

A Day In The Life (Responsibilities)
As a Principal Data Scientist, you'll lead the design and development of scalable ML systems for use cases such as menu recommendation, demand forecasting, offer targeting, and guest personalization. You will serve as a technical thought partner across teams, set best practices, and influence the roadmap for ML-driven products that support key business outcomes. Your work will directly shape strategic decisions and enhance customer experience at scale.

• Own the full machine learning lifecycle—from problem framing and data exploration to modeling, deployment, and monitoring—for mission-critical initiatives.
• Design and implement advanced ML and statistical models that improve product performance, operational efficiency, or customer insights.
• Collaborate with engineers, product managers, and business stakeholders to define project scope, success metrics, and integration strategy.
• Guide architectural decisions, set modeling standards, and champion best practices for experimentation, validation, and productionization.
• Mentor other data scientists and raise the technical bar through design reviews, feedback, and sharing domain expertise.
• Proactively identify areas where data science can create business value and lead cross-functional efforts to drive those opportunities forward.

What You'll Need To Thrive (Requirements)

• 10+ years of experience in data science with a proven track record of delivering production ML systems that drive measurable impact.
• Deep focus on mentorship, having leveled up more junior data scientist
• You've been a technical leader for core data science at Toast
• Deep knowledge of statistical modeling, machine learning (e.g., tree-based models, time series, deep learning), and model evaluation.
• Experience working with real-world product data at scale and translating ambiguous problems into well-scoped ML solutions.
• Experience with distributed data processing and training, real-time inference, and ML Ops frameworks
• Prior experience mentoring other data scientists or acting as a tech lead.
• Experience leading experimentation (e.g., A/B testing), causal inference, and real-time decision systems.
• Proficiency in Python and SQL, and experience with ML frameworks (e.g., scikit-learn, PyTorch, TensorFlow).
• Strong grasp of software engineering principles including modular design, version control, testing, and CI/CD.
• Hands-on experience with cloud platforms (preferably AWS), including tools like SageMaker, Athena, Glue, DynamoDB, and Bedrock.
• Excellent communication skills and the ability to influence both technical and non-technical stakeholders.
• Strong business acumen with the ability to align technical solutions with company goals.

Bonus
ingredients*
:

• An advanced degree in Computer Science, Statistics, or a related STEM field is preferred.
• Familiarity with MLOps tooling for monitoring, drift detection, retraining, and explainability.
• Experience fine-tuning LLMs and applying reinforcement learning from human feedback (RLHF) to improve model performance and alignment.

AI at Toast
At Toast, one of our company values is that we're hungry to build and learn. We believe learning new AI tools empowers us to build for our customers faster, more independently, and with higher quality. We provide these tools across all disciplines, from Engineering and Product to Sales and Support, and are inspired by how our Toasters are already driving real value with them. The people who thrive here are those who embrace changes that let us build more for our customers; it's a core part of our culture.

Our Total Rewards Philosophy
We strive to provide competitive compensation and benefits programs that help to attract, retain, and motivate the best and brightest people in our industry. Our total rewards package goes beyond great earnings potential and provides the means to a healthy lifestyle with the flexibility to meet Toasters' changing needs. Learn more about our benefits at

The base salary range for this role is listed below. The starting salary will be determined based on skills and experience. In addition to base salary, our total rewards components include cash compensation (overtime, bonus/commissions, if eligible), benefits, and equity (if eligible).

Pay Range

$143,000—$229,000 CAD

*Diversity, Equity, and Inclusion is Baked into our Recipe for Success*
At Toast, our employees are our secret ingredient—when they thrive, we thrive. The restaurant industry is one of the most diverse, and we embrace that diversity with authenticity, inclusivity, respect, and humility. By embedding these principles into our culture and design, we create equitable opportunities for all and raise the bar in delivering exceptional experiences.

We Thrive Together
We embrace a hybrid work model that fosters in-person collaboration while valuing individual needs. Our goal is to build a strong culture of connection as we work together to empower the restaurant community. To learn more about how we work globally and regionally, check out:

Apply today
Toast is committed to creating an accessible and inclusive hiring process. As part of this commitment, we strive to provide reasonable accommodations for persons with disabilities to enable them to access the hiring process. If you need an accommodation to access the job application or interview process, please contact

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