Job description

Lead Senior React Full Stack Engineer

Mississauga ON Canada – Onsite

Lead Senior React Full Stack engineer to build

AI-driven, micro-frontend web apps

on a modern, event-driven platform.

The Profile

•

10+ years

front-end / full-stack;

8+ years hands-on React

• Works independently with light direction; product-minded; banking / financial services a plus.

•

5+ years

leading and mentoring developers.

Must-Haves

•

React 18

(hooks, modern patterns) + strong

TypeScript

(ES2020+, generics).

•

Webpack 5 Module Federation / micro-frontends

— wiring host shells and remote MFEs.

(Vite / Next.js / other modern build setups count too.)

• State management (

valtio

/ Zustand / Redux / Recoil) and

react-router 6

•

API & data fetching

— REST (or GraphQL), and server-state libraries (

React Query / SWR

), with proper loading / error / cancellation handling.

• Design systems (

Mantine

/ MUI / Ant Design or similar) and HTML, CSS, SCSS/Sass; responsive, accessible UI (

WCAG / ARIA

• Real-time UI via

Server-Sent Events (SSE)

/ WebSockets (e.g., LLM token streaming).

•

Data-heavy dashboards

— building performant, data-dense UIs (tables, grids, charts) that handle large datasets smoothly.

• Testing:

Jest + React Testing Library

and E2E (

Cypress

/ Playwright).

• Git workflow (branching, PRs, code review), CI/CD, and performance / bundle optimization (code splitting, lazy loading, virtualization).

• Familiarity with

SSR / SSG

(Next.js or similar) is a plus.

Full-Stack

•

Node.js + NestJS

(or

Python

) building REST APIs / backend-for-frontend.

•

MongoDB / Mongoose, Postgres

Kafka (KafkaJS)

, JWT auth, OpenAPI / Swagger.

Strong Plus — AI Interface Skills

Priority: building

chat / assistant UIs

that stream responses token-by-token, code safely (XSS-safe), and visualize

agentic tool-use workflows

. Bonus: LLM / GenAI API integration (RAG, embeddings), accessibility (WCAG), and telemetry.

Nice to Have

• Has previously worked in startup

• Ability to wearing multiple hats in team