Senior React Developer (AI/AdTech) - Full-time - EMEA/APAC

Location: Remote-first (aligns well with GMT+2 to GMT+6) ·
Employment: Full-time
Team: Product Engineering
Reports to: Head of Engineering

About Themar

Themar is an AI-powered platform that helps brands and performance marketers create, personalize, and optimize ads at scale. We’re building a modern ad creation and experimentation workflow that blends a delightful editor, smart templates, and real-time insights — so teams can ship high-performing in minutes.

If you love shipping polished UIs, care deeply about performance and accessibility, and enjoy turning ambiguous product ideas into lovable experiences, you’ll feel at home here.

The role

We’re hiring a Senior React Developer to own core front-end experiences across the Themar product — from our creative editor and template system to analytics dashboards and collaboration flows. You’ll partner closely with design, product, data, and backend engineering to deliver fast, accessible, and reliable interfaces that customers love.

What you’ll do

● Lead development of high-impact product surfaces.
● Architect and evolve our React codebase for scale: state management, data fetching, routing, performance, and testing.
● Implement fast, accessible UI with strong UX polish (keyboard support, screen reader semantics, responsive layouts, dark mode).
● Own Web Vitals (LCP, CLS, INP, TTFB) — set targets, profile bottlenecks, and ship measurable improvements.
● Collaborate with design on a reusable component system (tokens, themes, accessibility patterns, motion).
● Establish and maintain CI/CD quality gates, story-based development, and robust automated tests.
● Mentor engineers through code reviews, pairing, and technical design docs.

What you’ll bring

● 5+ years building production web apps with React and TypeScript.
● Deep experience with Next.js (App Router, RSC, SSR/SSG, edge/runtime configs) or Vite-based setups.
● Strong command of data fetching and caching (TanStack Query/SWR) and state management (Redux Toolkit/Zustand/Jotai).
● Excellence in testing (Jest or Vitest + React Testing Library; Playwright/Cypress for e2e).
● Practical performance skills: code-splitting, Suspense/streaming, memoization, virtualization, image optimization, profiling.
● Accessibility fluency (WCAG 2.2 AA, ARIA patterns, focus management, color contrast).
● Experience building and maintaining design systems (Storybook, tokens, theming) and CSS tooling (Tailwind/CSS Modules/Styled Components).
● Comfortable integrating APIs (REST/GraphQL), auth (OAuth/OIDC), and analytics/experimentation pipelines.
● Proactive ownership, crisp communication, and product sense.

Nice to have

● Rich-editor or canvas experience (e.g., Slate, ProseMirror, TipTap, Konva/Fabric.js, WebGL/Web Workers, PWAs).
● Familiarity with ad tech, creative tooling, or growth experimentation.
● Observability & reliability chops (Sentry, OpenTelemetry, Datadog, feature flags).
● Security-conscious development (CSP, XSS/CSRF mitigation, dependency hygiene).

Our stack (current & planned)

React 18/19 · TypeScript · Next.js · Tailwind · TanStack Query · React Hook Form + Zod ·
Storybook · Jest/Vitest + RTL · Playwright · Node.js/Edge runtime · PostgreSQL · Redis ·
Vercel/AWS · CI/CD with GitHub Actions · Sentry

What success looks like

30 days: ship a meaningful UI improvement, raise test coverage for a core route, and demonstrate understanding of our architecture.
60 days: own a product surface end‐to‐end (design PRDs → technical design → implementation → rollout) with measurable Web Vitals gains.
90 days: lead a cross-functional initiative (e.g., editor performance, design system, or analytics usability) and mentor others through reviews and pairing.

How we work

● Customer-first, outcome-driven, and experiment-friendly.
● Small squads, short feedback loops, and written design docs.
● Pragmatic engineering — we optimize for leverage and maintainability.

Compensation & benefits

● Competitive salary + meaningful equity (range customizable by region and seniority).
● Health & wellness coverage.
● Home office stipend & learning budget.
● Remote-first flexibility with occasional team offsites.

Remote within overlapping hours of GMT+2 to GMT+6.