Software Engineer, Full Stack (Senior, Staff+)

Kustomer • New York, NY

7d • $130,000 - $215,000 • Remote

About The Position

Kustomer is hiring a Full Stack Software Engineer to join our Engineering team. In this role, you'll work as part of a pod: a 3–5 person team that picks up a high-priority initiative, ramps quickly, ships end-to-end, and moves on to the next one. You'll be a capable, adaptable engineer who can walk into any part of the codebase, understand it, and make it better. You'll ship new capabilities, improve performance, and contribute to the evolution of our architecture using technologies like Node.js, React, Golang, and AWS, collaborating closely with your pod leader and teammates across engineering, product, and design.
AI is a core part of how we build. You'll use AI tools daily to move faster and raise the bar on what you ship. You'll also help build AI-powered product capabilities that meaningfully improve the customer experience.
We're looking for engineers with strong technical judgment, a high bar for craft, and real curiosity about how systems, product, and AI intersect. You take initiative, thrive in ambiguous problem spaces, and own your work end-to-end, from design through production. Not because someone's tracking it, but because you genuinely care about what you're building. If you want your work to directly shape the product and the team around you, we'd love to hear from you.

Requirements

• 7+ years of progressive software development experience and a Bachelor's degree in Computer Science, Software Engineering, or a related field
• Comfortable working across frontend and backend. Ability to follow the work wherever it goes and not be blocked by an unfamiliar layer.
• Understanding of how systems work at depth and experience with cloud platforms like AWS or similar. Knowledge of data structures, algorithms, concurrency, distributed systems, API design, database internals.
• Ability to read READMEs, trace execution, ask sharp questions, and start adding value fast.
• Own the outcome, not just the ticket. Ability to raise risks early, communicate progress proactively, and care about what ships.
• Ability to diagnose and debug complex issues, optimize application performance, and identify areas for improvement.
• Hands-on experience with modern AI developer tools, such as Cursor or Claude Code, and a working practice around using them as a force multiplier for code comprehension, test scaffolding, documentation, debugging, and ramp.

Nice To Haves

• Familiarity with integrating AI or ML-powered capabilities into web applications, even at a prototype or feature level
• Exposure to integrating third-party AI APIs or frameworks (e.g., OpenAI, Anthropic, LangChain, or vector databases like Pinecone)
• Interest in exploring how AI can enhance developer workflows and improve product functionality
• Github activity showing thoughtful, relevant contributions

Responsibilities

• Ship full-stack features end-to-end as a member of a pod, owning scope from problem definition through production, using technologies like Node.js, React, Golang, MongoDB, ElasticSearch, and AWS
• Develop APIs and integrate with external services and databases, ensuring data integrity and security
• Build front-end interfaces with a focus on user experience, responsiveness, and accessibility
• Design and build AI-powered features that improve the user experience and platform efficiency
• Partner with PMs, engineers, and your Pod Lead to shape requirements, design, UX, and scope tradeoffs, communicating progress proactively along the way
• Optimize application performance through caching, efficient algorithms, and database indexing
• Write thorough unit and integration tests to ensure quality and reliability
• Conduct code reviews, provide constructive feedback, and mentor junior engineers to uphold a high quality bar
• Share production support responsibility on a rotating basis, including on-call and bug triage, distributed equitably across the team
• Stay current with emerging AI tools, full-stack technologies, and industry trends — and actively propose and champion those that improve team velocity, quality, and development practices
• Ramp quickly on unfamiliar parts of the codebase aided by AI tooling, consistent code hygiene, and a deep engineering foundation

Benefits

• Competitive salaries
• Stock options
• 100% healthcare coverage (U.S.)
• 401K (U.S.)
• WiFi and Mobile reimbursement (U.S.)
• Generous vacation policy (U.S.)
• Pension (UK)
• Supplemental health insurance (UK)
• Other perks (UK)

What This Job Offers

• Job Type: Full-time
• Career Level: Senior