Senior Full Stack Engineer

Posted yesterday

sincereSomerville (MA)

Software DevelopersCustom Computer Programming Services

SENIORITY

Senior

About the role

Overview As a Senior Full Stack Engineer at Sincere, you own end-to-end product improvements across a broad stack, influencing customer value and UX. You collaborate with product, design, and Dev Ops to identify pain points, shape solutions, and ship high-quality features. You’ll leverage AI-assisted development tools and monitor product impact to drive pragmatic tradeoffs and reliable experiences. This role offers ownership, cross-functional impact, and opportunities to shape large-scale customer-facing applications. Compensation / Benefits 100% Health, Dental & Vision coverage 401K Plan with Profit Share Annual bonus potential Health & Wellness stipends Paid time off plus 12 paid holidays & Summer Fridays Paid parental leave Responsibilities Build full-stack features across Ruby on Rails and Next.js Own product initiatives end-to-end from ideation to launch and iteration Partner with product managers and designers to identify pain points and opportunities Leverage AI-assisted tools (Claude Code, Codex) to explore, develop, test, and ship Make practical technical decisions balancing speed, quality, and maintainability Deliver polished, user-focused experiences with strong UXUse Datadog and Mixpanel to monitor production behavior and inform decisions Champion new ideas and continuously improve products and engineering practices Key requirements 7+ years of professional software development Proficiency across Ruby on Rails, Type Script, React, Next.js, MySQL/Postgres, Redis, MongoDB, Sidekiq, Open Search, AWS, Docker Fluent with AI-assisted development tools (Claude Code, Codex)Experience building and maintaining large-scale customer-facing web apps Product-minded with strong instincts for customer needs and business value Self-starter who brings structure to undefined problems and executes Collaborative with Dev Ops, understanding of cloud infrastructure (AWS), Terraform Pragmatic improvement of existing architectures and codebases Collaborative and low-ego Strong communication and craft pride Detail-oriented with a focus on customer experience Ruby on Rails Type Script React

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