Senior Frontend Engineer (React)

TL;DR

Senior Frontend Engineer (React): Architecting and delivering complex, scalable frontend systems for a digital marketing insights platform with an accent on state management, web performance, and data-heavy applications. Focus on reducing codebase complexity, mentoring engineers, and collaborating with product managers to shape feature scope.

Location: Hybrid (Toronto)

Company

A digital marketing intelligence platform that provides insights into the digital ecosystem to help customers optimize their strategy.

What you will do

• Architect and deliver complex, scalable frontend systems while removing unnecessary codebase complexity.
• Partner with Product Managers to co-author requirements and ensure engineering feasibility during ideation.
• Lead technical decision-making for medium-to-large features, ensuring the delivery of actual customer value.
• Mentor junior and mid-level engineers via code reviews, pair programming, and instilling quality-first habits.
• Proactively identify and resolve bottlenecks, technical debt, and systemic frontend issues.
• Collaborate with Data Science and Backend teams to ensure seamless data flow and end-to-end system reliability.

Requirements

• Deep specialization in modern JavaScript, TypeScript, and React.
• Proven ability to architect complex state management using tools like TanStack Query, Zustand, Redux, or MobX.
• Experience designing maintainable systems capable of handling high complexity.
• Track record of elevating peer skills through pattern teaching and best practices.
• Proficiency in writing robust unit and integration tests using Jest, Cypress, or Playwright.
• Deep understanding of web performance, browser internals, and optimization for data-heavy applications.

Nice to have

• Experience in data visualization and handling large datasets with heavy DOM manipulation.
• A portfolio or GitHub history demonstrating clean code and architectural problem-solving.
• Familiarity with Ruby on Rails framework and NoSQL/Columnar databases like MongoDB or Clickhouse.

Culture & Benefits

• Fast-paced startup mindset within a lean and flat organization.
• Opportunity to take ownership of major technical components and shape the product's technical direction.
• Environment focused on technical excellence, mentoring, and quality-first engineering.
• Cross-functional collaboration between engineering, product, and data science teams.