Senior Frontend Engineer

Senior Frontend Engineer
Company: Invaluable, an LSI Company
Location: US, remote

About Us

Invaluable, an LSI Company, is one of the world’s largest online live auction marketplaces for antiques, fine art and collectibles. We’re modernizing the auction experience by connecting millions of passionate bidders and buyers with auction houses across the globe. Our industry-leading live online bidding platform lets customers participate in premier auctions in real time—from their home, office, or mobile device.

Role Summary

As a Senior Frontend Engineer, you’ll build and maintain customer-facing experiences that power live online auctions. You’ll deliver new features, improve performance and reliability, reduce technical debt, and help shape frontend standards and long-term strategy. You’ll collaborate closely with product, design, and engineering partners while mentoring teammates and raising the bar through thoughtful engineering practices.
We’re an AI-forward engineering team. You’ll use AI tools (Claude and Claude Code are our toolset of choice) as an everyday force multiplier, multiplying what you can deliver while staying fully accountable for the quality, security, and maintainability of everything you ship. We use AI under a clear company AI policy: vetted, approved tools with strong data protections, careful handling of customer and confidential data, and the expectation that engineers review AI output as carefully as a junior colleague’s work before it carries their name.
Our Tech Stack: Node/Express, Handlebars, React, Redux, Backbone.js, jQuery, Bootstrap 3/4, Figma, Jest, Cypress, Claude / Claude Code.

Key Responsibilities

• Build and ship features end-to-end across any tier of the Invaluable platform, from implementation through testing and deployment.
• Improve quality and maintainability by refactoring legacy areas (Backbone, Handlebars/jQuery) and reducing technical debt with pragmatic, incremental changes.
• Own reliability and performance: diagnose production issues, squash bugs, and improve UX with measurable outcomes.
• Drive frontend architecture and standards: propose patterns, tooling, and conventions that improve developer experience and long-term maintainability.
• Build with AI as a teammate: Use AI tools (Claude Code preferred) to plan, build, test, debug, review, and document your work. Treat AI the way you’d treat a capable junior colleague: hand it real work, review what it produces, and ship only what you’d put your name on. Our AI policy gives you approved tools and clear data-handling rules, so you can use AI on day one without second-guessing what’s allowed.
• Raise the team’s AI fluency: share effective workflows, build reusable context (project instruction files, prompts, skills, MCP integrations), and help teammates adopt AI-assisted practices safely and effectively.
• Collaborate effectively through pairing, code reviews, and shared problem-solving, including communicating clearly across time zones.
• Mentor and support engineers by sharing best practices, offering feedback, and helping others grow through guidance and technical leadership.
• Partner with Product and Design to clarify requirements, scope of work, identify tradeoffs, and deliver high-quality user experiences.
• Champion inclusive teamwork by actively engaging with colleagues while maintaining space for others to contribute.

Required Skills & Qualifications

• 5–7+ years of professional frontend engineering experience (or equivalent practical experience).
• Strong proficiency with JavaScript and modern frontend development practices.
• Significant experience with React (and ideally Redux) in production.
• Experience working in Node/Express environments (e.g., local tooling, server-rendered integrations, API coordination).
• Comfort working in and improving legacy codebases (e.g., Backbone, Handlebars, jQuery) with an ability to modernize safely over time.
• Strong testing discipline: experience writing and maintaining React Testing Library unit tests and Cypress end-to-end tests; values meaningful coverage.
• Hands-on, daily use of AI coding tools (Claude / Claude Code preferred, or comparable tools) across the development lifecycle, with a practical understanding of how LLMs work—context, prompting, and limitations such as hallucination—and disciplined verification of AI-generated code.
• Sound data-handling judgment when using AI: keeps credentials, customer data, and personal information out of prompts and works within approved tools and company policy.
• Strong technical judgment: able to propose solutions, explain tradeoffs, and make pragmatic decisions for long-term project health, including knowing when and how to apply AI and when not to.
• Collaborative and kind: enjoying pairing, code reviews, and knowledge sharing; open to learning and teaching.

Preferred Qualifications

• Experience with ecommerce or marketplace products (or adjacent high-traffic consumer experiences).
• Familiarity with UI systems and design collaboration workflows (e.g., Figma, design systems, accessibility).
• Experience improving front-end performance and observability in production.
• Experience with agentic AI workflows and context engineering (e.g., running multi-step tasks with Claude Code, maintaining CLAUDE.md project files, building skills or MCP integrations).
• A track record of measurable productivity or quality gains from AI adoption, for yourself or your team (e.g., faster delivery, expanded scope, improved test coverage).
• BA/BS in a STEM-related field and 5–7 years of related experience, or an equivalent combination of education and professional experience that demonstrates the required skills.

What We Offer 

• Competitive Compensation: $140,000-170,000 annually plus profit share bonus.
• 100% remote work for the entire company. 

• Approachable leadership.  
• A great team of smart, supportive people. 
• Health care, dental, vision, life and disability insurance
• 401(k) matching. 
• Tuition Reimbursement

• Employee assistance plan. 

• Paid parental leave. 

Commitment to Diversity

We believe diverse perspectives drive innovation and excellence. If you meet the minimum qualifications, we encourage you to apply—even if you don’t meet every preferred qualification. We welcome applicants from all backgrounds, including those traditionally underrepresented in technology, and are committed to building an inclusive, equitable workplace where ever