Principal AI Engineer

About the Role

We are looking for a Principal AI Engineer who moves fast, experiments relentlessly, and ships agentic AI systems that solve real problems.

This is a hybrid, office-based position which requires you to work 3 days per week (Tuesdays, Wednesdays and Thursdays) in our Boston, MA (Financial District) Headquarters.

Who you are:

• Doer: hands‑on with code and you experiment daily.
• Fast and intelligent: you make smart decisions quickly and iterate.
• Experimentation‑obsessed: you validate through building.
• Comfortable with ambiguity: you forge ahead when the path isn’t clear.

• Build and deploy agentic AI systems.
• Perform research spikes to evaluate scope and feasibility.
• Help set technical direction through working prototypes and rapid experimentation.
• Create evaluation datasets, labeling workflows, and instrumentation to improve agent performance.
• Move from idea to production‑ready implementation at speed.

• 10+ years of engineering experience shipping impactful products.
• 2+ years building agentic AI systems.
• Strong product sense and an understanding of how to integrate agents into user experiences.
• Experience with agentic frameworks. We use Mastra AI, so either experience with or a willingness to learn Typescript.
• Bias toward action and rapid decision‑making.
• Ability to work 3 days per week (Tuesdays, Wednesdays and Thursdays) to work on‑site in Boston, MA.

• ML engineering or data science background.
• Experience with evaluation frameworks, observability tools, or synthetic data generation.
• History of 0-to-1 projects.

Salary range $200,000 – $250,000 plus benefits, bonus opportunities and stock options. Final salary may vary depending on skills, location, and/or experience.

Validity is proud to be an equal opportunity employer. We are committed to providing equal employment opportunities to all employees and applicants for employment regardless of actual or perceived race, color, ancestry, national origin, citizenship, religion or creed, age, physical or mental disability, medical condition, AIDs/HIV status, genetic information, military and veteran status, sex, parental status (including pregnancy and pregnancy‑related conditions, childbirth, post‑childbirth, nursing mother, parent of a young child and parent of a foster child), gender (including gender identity and expression), sexual orientation, marital status (including registered domestic partner status), or any other characteristic protected by applicable federal, state, or local law.

Please review our Applicant Privacy Notice before submitting any information.