Frontend Engineer - UI/UX

Our client is an exciting AI Start up company and they have an immediate need for a Frontend Engineer. This position will own the decision surface enterprise that senior leaders will act on every day. You will own that experience end to end: the widget and data-visualization system, the design system, and the onboarding and polish that make enterprise users want to live in the product every day.

Responsibilities

• Own and evolve the decision surface: the SSR routes, the auth and session flow, and the overall front-end architecture.
• Build out the widget and data-visualization system: chart types, per-source breakdowns, color palettes, and an add-widget builder, driven by the front-end state layer.
• Shape the insights deck and Kanban: the surfaces where operators triage AI-detected insights, drag them across columns, assign owners, and work action-step and comment threads.
• Wire the front end to the backend data API, tuning the metric catalog, theming, and export layers.
• Define and grow a coherent design system: components, tokens, motion, and empty, loading, and error states, so new surfaces ship fast and feel consistent.
• Build onboarding and connection flows (OAuth-backed source connections, first-run experiences) that get a new enterprise tenant to first insight quickly.
• Partner directly with the Head of Engineering on product and UX decisions, and help define what polished means.
• Keep the front end honest with the multi-tenant model: every view is tenant-scoped and never leaks across boundaries.

Requirements

• Strong TypeScript and React experience and a genuine eye for UI and UX;
• 2-4 years of experience in Front End and UI/UX
• Real data-visualization sensibility; Experience building charts and dashboards and can reason about representing multi-source, time-series data clearly.
• Comfortable owning a front end end to end: component architecture, state management, performance, and accessibility.
• Experience integrating REST and JSON APIs and shaping and normalizing server data for the UI.
• Product instinct; you can take an ambiguous request to make a flow better and turn it into shipped, tested UI.
• Comfortable in a startup environment: high ownership, low ceremony, comfortable with early-stage ambiguity.
• Able to be in the Toronto office two days a week.

Nice to Haves

• Experience with a modern SSR or islands framework and a utility-first CSS framework.
• Built or maintained a design system or component library.
• Familiarity with multi-tenant SaaS patterns (Postgres, row-level security).
• Exposure to the digital advertising or marketing-analytics domain.
• Comfort dipping into the Python backend when a feature needs it.