Senior Full-Stack Engineer (Ruby & Next.js)

Senior Full-Stack Engineer (Ruby & Next.js) Location: Remote (US) — Preference for candidates based near New York City, NY or Los Angeles, CA Employment Type: Full-time / Contractor We are looking for a Senior Full-Stack Engineer with deep expertise in Ruby (Ruby on Rails) and Next.js / React to join our team. In this role, you will lead the architecture and implementation of scalable, high-performance web applications, bridging modern backend architecture with fast, responsive frontend experiences. This is a primarily remote role across the US, but because we host periodic in-person team building sessions and collaborative offsites, proximity to our hubs in New York City (NYC) or Los Angeles (LA) is highly preferred. Key ResponsibilitiesFull-Stack Architecture: Design, build, and maintain scalable web applications using Ruby on Rails for robust API/backend systems and Next.js for modern, high-performance user interfaces.Frontend Excellence: Leverage modern Next.js features (App Router, Server-Side Rendering, Server Actions) and React patterns to deliver intuitive, high-speed UX.Backend & Database Management: Write clean, modular, and well-tested Ruby code. Optimize database queries (PostgreSQL / Redis) and handle asynchronous background processes.System Performance: Ensure high availability, microservices/API integration, and low-latency response times across the stack.Technical Leadership: Conduct code reviews, mentor team members, and partner with product managers and designers to drive architectural decisions. Required Qualifications (Must-Haves)Experience: 5+ years of professional software engineering experience, with at least 3+ years in a Senior Full-Stack capacity.Core Stack Proficiency:Backend: Strong, hands-on expertise in Ruby on Rails (REST/GraphQL APIs, Active Record, Sidekiq).Frontend: Advanced mastery of Next.js and React (TypeScript experience is a strong plus).Database & Cloud: Strong knowledge of relational databases (PostgreSQL) and cloud infrastructure/deployments (AWS, GCP, Heroku, or Vercel).Architectural Acumen: Proven track record of designing scalable full-stack applications, handling data modeling, and optimizing web performance.Location & Availability: Based in the United States, ideally within commuting distance of NYC or LA for occasional in-person offsites and team gatherings. Preferred Qualifications (Nice-to-Haves)Proficiency with TypeScript in Next.js applications.Experience with caching layers, message queues, and background processing (Redis, RabbitMQ).Familiarity with CI/CD pipelines, containerization (Docker), and automated testing frameworks (RSpec, Jest, Cypress).Prior experience working in fast-paced startup or scale-up environments.