Senior Backend Engineer

Recruiting From Scratch•San Francisco, CA

2d•Onsite

About The Position

Our client is building a modern B2B payments platform designed to bring the B2B economy online through seamless, automated payment workflows. The platform sits at the intersection of payments, data infrastructure, and enterprise software, with backend systems directly powering critical payment decisions and customer experiences. The engineering organization is relatively lean, creating an environment where individual engineers have significant ownership and direct impact on the product. This is a high-agency engineering environment where engineers are expected to take ambiguous real-world problems, define the right solution, and own projects from initial design through production deployment. As a Senior Backend Engineer, you'll work on core data and payments infrastructure while building reliable systems, APIs, internal tools, and services that directly impact business outcomes. The ideal candidate combines strong backend engineering fundamentals with high ownership, product judgment, and the ability to operate effectively in ambiguous startup environments.

Requirements

5+ years of professional backend software engineering experience
Strong experience building production backend systems
Experience working with TypeScript and Node.js
Experience designing APIs and backend services
Experience with SQL and relational databases
Experience with PostgreSQL preferred
Experience working with AWS or similar cloud infrastructure
Experience building data-intensive or transaction-heavy systems
Experience working on payments, financial infrastructure, fintech, or other high-correctness systems preferred
Experience owning projects end-to-end
Experience operating in ambiguous and rapidly changing environments
Strong startup or high-growth technology company experience preferred
Experience working in lean engineering organizations
Experience collaborating closely with Product and cross-functional teams
Strong understanding of backend architecture and distributed systems
Experience building reliable and scalable production systems
Strong debugging and technical problem-solving ability
Experience making technical decisions independently
Demonstrated ability to deliver production software with limited oversight
Experience balancing speed, reliability, and correctness
Strong product engineering mindset
Ability to connect technical decisions to business and customer outcomes
Strong TypeScript experience
Strong Node.js backend development experience
Strong SQL fundamentals
Experience with PostgreSQL or similar relational databases
Experience designing REST APIs
Strong backend service architecture knowledge
Experience working with AWS
Experience with production cloud infrastructure
Strong understanding of data modeling
Experience designing service contracts and APIs
Experience building distributed or highly available backend systems
Strong understanding of reliability and fault tolerance
Experience optimizing backend latency and performance
Experience working with high-volume data systems
Strong understanding of database performance and query optimization
Experience building internal tooling
Experience with data infrastructure preferred
Experience with Snowflake or modern data platforms preferred
Experience building payment systems or financial infrastructure preferred
Strong testing and production engineering practices
Experience monitoring and debugging production systems
Strong system design fundamentals
Ability to make architecture tradeoffs based on scalability, reliability, and business requirements
Ability to write clean, maintainable, production-quality code
Strong understanding of software engineering best practices
Ability to independently design and implement backend systems
Bachelor's degree preferred
Computer Science, Engineering, Mathematics, or related technical disciplines preferred
Strong technical academic background is a plus
Exceptional professional engineering experience can compensate for academic pedigree
High ownership mentality
Strong agency and independence
Comfortable operating without detailed specifications
Strong problem-solving ability
Strong product intuition
Business-oriented engineering mindset
Comfortable working through ambiguity
Bias toward action
Strong communication skills
Ability to explain technical decisions clearly
Strong collaboration skills
Comfortable working with Product and cross-functional stakeholders
Strong judgment around technical tradeoffs
High attention to detail
Strong sense of accountability
Comfortable making decisions with incomplete information
Ability to balance speed with reliability
Customer-oriented mindset
Strong execution ability
Comfortable owning projects from start to finish
Proactive approach to identifying problems
Low-ego and collaborative working style
Comfortable in lean engineering organizations
Excited by high-impact, high-responsibility environments
Strong learning mentality
Comfortable working in a fast-moving startup environment
Able to work effectively on-site in San Francisco
Willingness to work five days per week in-office, with flexibility for exceptional candidates

Responsibilities

Build and own production backend systems powering core data and payments infrastructure
Design scalable backend services using TypeScript and Node.js
Build reliable APIs, services, data models, and contracts used across the organization
Develop systems where correctness, reliability, and data integrity are critical
Build and improve core payment infrastructure and workflows
Work on data infrastructure supporting payment decisions and customer experiences
Develop internal tools that help teams review data and understand system decisions
Build tooling that enables internal teams to operate more efficiently without sacrificing quality
Own ambiguous technical projects from problem definition through production deployment
Identify problems independently and propose effective technical solutions
Break large technical problems into production-ready increments
Ship production systems quickly while maintaining engineering quality
Improve backend system reliability, latency, and correctness
Design systems that can scale with rapidly increasing transaction and data volumes
Build robust APIs and services consumed by internal and external systems
Design and maintain backend data models and service contracts
Collaborate closely with Product and other engineering teams
Translate product requirements and business problems into technical solutions
Make architecture and engineering tradeoff decisions independently
Take ownership of technical decisions rather than waiting for detailed specifications
Monitor and improve system performance and reliability
Identify technical risks and proactively address them
Build systems that are maintainable, observable, and resilient
Work closely with stakeholders to understand business impact and customer needs
Contribute to engineering standards and best practices
Help establish scalable patterns for backend development
Operate as a highly autonomous engineer within a lean engineering organization
Take projects from initial concept through design, implementation, launch, and iteration
Help shape the technical direction of core payments and data infrastructure