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Senior Principal Software Engineer, R&D

Toronto, Canada💼 Full-time💰 $208,000–$333,000🗓 2026-09-28 → 2026-09-29

Core

Establish technical direction for complex, early-stage product concepts and drive architecture decisions for large-scale new products in the payments and commerce domain.

Role type

Senior Principal Software Engineer (R&D, AI/LLM focus)

Builds

Complex, large-scale new product concepts and data platforms for Mastercard's business units

Domain

Fintech / Digital Payments / Generative AI

Deliverable

production ML models

Required skills

Generative AI and LLM architecture, Agent orchestration frameworks (LangGraph, OpenAI Agents SDK, Codex SDK), Cloud platforms (Databricks, Snowflake, AWS, Azure), Java/Spring Boot, React/TypeScript, Postgres, Data product development, Architecture pattern creation, Technical strategy under uncertainty

Preferred skills

Thought leadership (publications, patents, open source), Coaching senior engineers, Cross-functional influence without direct authority

Technologies

LangGraph, OpenAI Agents SDK, Codex SDK, Databricks, Snowflake, AWS, Azure, Java, Spring Boot, React, TypeScript, Postgres

Responsibilities

Define scalable solution architectures for early-stage products, Establish engineering best practices for AI-assisted development, Set technical direction for applications and integrations, Lead architecture implementation for Data Platforms, Influence technical direction across R&D and product teams, Identify technical risks and design experiments to de-risk concepts, Coach senior engineers and raise quality standards

Seniority

Senior Principal, hands-on IC with strategic influence

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