We are looking for a passionate and experienced Senior Software Engineer to join our Workflow Builder UI pillar. In this role, you will be the primary craftsperson of our next-generation drag-and-drop workflow experience – the visual layer that thousands of teams rely on to design, configure, and automate their processes. You will shape every pixel and interaction, working at the intersection of high-performance rendering, rich component design, and developer experience.

This is your opportunity to build a product that end-users see and touch every single day, deeply integrating modern React patterns, leading UI component libraries, and – as a nice-to-have – MCP UI tooling to accelerate development velocity.

You will work remotely from Bulgaria and will be reporting to an engineering leader.

You Will:

Own the Workflow UI Experience

• Architect, build, and iterate on the Workflow Builder front-end, delivering a performant, accessible, and delightful drag-and-drop editing experience.
• Drive component design, layout systems, and interaction patterns that scale across Smartsheet's enterprise customer base.
• Champion visual quality, pixel-precision, and a high bar for UX polish throughout the development lifecycle.

Develop with React & UI Libraries

• Build production-grade features using React (v18+), leveraging hooks, context, concurrent rendering, and Suspense for advanced UI behaviors.
• Integrate and extend component libraries (e.g., MUI, Radix UI, Shadcn/ui, or internal design system components) to create a consistent, reusable UI language across the product.
• Evaluate and champion the adoption of new React capabilities and ecosystem tooling that improve developer productivity and user experience.

Build Scalable and Secure Services

• Develop scalable back-end services and APIs with a security-first mindset, ensuring high availability and performance in our multi-cloud environment (primarily AWS).
• Create and maintain API integrations between internal and external systems. Implement and test API solutions to ensure they meet functionality, performance, and security standards. Monitor API performance and address any integration challenges or issues.
• Participate in architectural discussions and code reviews, advocating for front-end best practices: code splitting, memoization strategies, accessibility (WCAG AA), and performance budgets.
• Define and uphold front-end coding standards, patterns, and automated testing strategies (unit, integration, visual regression) across the pillar.

Deliver High Quality at Scale

• Write comprehensive unit and integration tests (Jest, Cypress, Playwright) with a strong culture of test-driven development and visual regression coverage.
• Monitor front-end performance metrics (Core Web Vitals, bundle size, rendering throughput), identify bottlenecks, and drive measurable improvements.
• Partner with UX designers to translate wireframes and prototypes into refined, fully accessible UI components.

Mentor & Lead

• Serve as a UI subject matter expert for the team, mentoring junior and mid-level engineers on React best practices, component design, and scalable state management.
• Contribute to technical roadmap planning and effort estimation for UI-heavy features, surfacing risks and tradeoffs to engineering leadership.

Strategically apply AI Tools

• Champion the use of AI-assisted development tools (GitHub Copilot, Claude, Cursor, etc.) within the team to accelerate feature development and code quality improvements.
• Build and evaluate AI-powered features in the Workflow Builder that leverage generative AI or agentic workflows to deliver measurable customer value.

You Have:

• 5+ years of professional front-end software engineering experience with a strong focus on UI/UX-facing product work.
• Proficiency in React (v17+), including hooks, context API, concurrent features, and performance optimization techniques (memoization, virtualization, profiling) and at least one major programming language such as Java, Kotlin, Go, or Python with a proven history of building scalable and secure applications.
• Deep experience with TypeScript, HTML5, and CSS3 (including CSS custom properties, CSS Modules, Grid, and Flexbox).
• Hands-on experience integrating and customizing UI component libraries (MUI, Radix UI, Shadcn/ui, or similar) and/or contributing to an internal design system.
• Strong understanding of state management patterns (Redux Toolkit, Zustand, Jotai, or React Query) and when to apply each in complex application scenarios.
• Experience building accessible UIs (WCAG 2.1 AA compliance) and a genuine understanding of why accessibility matters.
• Proven track record of optimizing front-end performance (code splitting, virtual scrolling, React.memo/useMemo tuning, bundle analysis, memory profiling).
• Experience with modern front-end testing frameworks (Jest, Cypress, Playwright, or Storybook visual regression).
• Excellent verbal and written communication skills in English; proven ability to collaborate across design, product, and engineering stakeholders.
• 1+ year professional experience leveraging AI-based workflows to author, review, and maintain code.
• 1+ year building AI-augmented product features that incorporate generative AI or agentic workflows to solve real customer problems
• Legally eligible to work in Bulgaria on an ongoing basis.
• Fluency in English is required.

Nice to have:

• Experience with MCP UI tooling or Model Context Protocol integrations in front-end workflows.
• Familiarity with canvas/SVG rendering libraries (Fabric.js, Konva, React Flow, or custom WebGL/Canvas 2D) for building interactive workflow diagram surfaces.
• Exposure to micro-frontend architectures and module federation in large-scale React applications.
• Background in drag-and-drop UI frameworks (dnd-kit, react-beautiful-dnd, interact.js, or similar).
• Advanced certifications in front-end (e.g., Google UX Design, AWS Certified Developer) or relevant open-source contributions.