Senior Software Engineer / Core Product Systems

Calliere • New York, NY

2d • $250,000 • Onsite

About The Position

A well-funded technology company is adding a senior engineer to a small product team building software for complex, high-volume business operations. The team works on the parts of the product that are hardest to get right: systems that transform messy inputs into dependable outputs, coordinate work across services, and give users confidence that important processes have completed accurately. If you enjoy backend engineering with genuine ownership—rather than shipping isolated tickets—this is a chance to help shape a product, its architecture, and the engineering standards around it. You’ll design and deliver the services behind a sophisticated B2B platform. Your work will touch the product’s most foundational capabilities: representing customer-specific logic, coordinating work that spans multiple steps, and making the resulting behavior transparent to both internal teams and end users. You’ll be expected to work comfortably across the lifecycle: Dig into ambiguous requirements and turn them into practical technical plans, Build durable APIs, services, and data models, Make difficult processes resilient to failures, retries, and unexpected inputs, Improve developer tooling, production visibility, and operational confidence, Partner closely with product, design, and customer-facing teammates, Participate in architecture decisions and help establish engineering patterns as the company grows, Mentor teammates and raise the quality bar through thoughtful reviews and hands-on collaboration.

Requirements

• Backend or platform engineering in a growing product company
• Building data-rich applications with complex business rules
• Relational databases, APIs, transactions, and asynchronous processing
• Service architecture, background jobs, queues, or event-driven systems
• Designing adaptable systems without over-engineering every edge case
• Debugging difficult production issues across application, data, and infrastructure layers
• Working with cloud platforms and modern deployment practices
• Writing clear technical documentation and explaining tradeoffs to non-specialists
• A strong candidate can take a broad product problem, identify the true constraints, and create a solution that is understandable for the next engineer to maintain.

Nice To Haves

• Experience with Python, Go, Java, Ruby, TypeScript, C#, or another modern server-side language
• Familiarity with cloud infrastructure and production observability
• Experience working on workflow-heavy, data-intensive, or configuration-driven products
• Exposure to enterprise software, operations platforms, infrastructure tooling, or vertical SaaS
• Interest in joining an in-person team in New York

Responsibilities

• Dig into ambiguous requirements and turn them into practical technical plans
• Build durable APIs, services, and data models
• Make difficult processes resilient to failures, retries, and unexpected inputs
• Improve developer tooling, production visibility, and operational confidence
• Partner closely with product, design, and customer-facing teammates
• Participate in architecture decisions and help establish engineering patterns as the company grows
• Mentor teammates and raise the quality bar through thoughtful reviews and hands-on collaboration

Benefits

• Meaningful seat at the table in a company solving non-trivial problems for serious customers.
• Technically substantial, commercially important, and broad work.
• Opportunity to build real systems, own difficult problems, and help a product team scale without losing quality and care.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed