Senior Fullstack Engineer

Recruiting From Scratch•Boston, NY

3d•Hybrid

About The Position

The Senior Engineer will join the Growth Pod and own backend systems and front-end experiences that move businesses from sign-up through onboarding, activation, and purchase. The role covers sign-up/onboarding, discovery, and checkout, including event-driven systems that track account lifecycle states and trigger appropriate actions, as well as customer-facing experiences that educate customers and support conversion. The engineer will investigate funnel performance directly using data, work across Product, Data, and Risk, and take ownership of ambiguous problems without an established playbook. The role includes integrating identity verification and risk providers and handling sensitive credit and payment data with care. AI agents are used to accelerate development, testing, and analytical work, with the engineer responsible for reviewing and verifying outputs, especially those involving credit, payment, verification, or customer messaging. The listed technology stack includes TypeScript/Node.js, GraphQL, PostgreSQL, Snowflake, dbt, OpenSearch, Spark/EMR/Glue, Keycloak, Okta, Jenkins, GitOps, AWS, Kubernetes, and Grafana. The position is remote-first, with a hybrid arrangement intended for Boston and New York-based employees. In New York, engineers focused on future fulfillment work are expected to use the Midtown hub; the Boston hub is expected to develop, initially likely as a coworking space. There are no core working hours for the global remote team.

Requirements

4–7 years of experience.
Strong backend product engineering experience, likely with TypeScript/Node.js, including ownership of funnel-critical production services.
Hands-on experience with event-driven architectures and workflow orchestration.
Experience designing experiments, defining guardrail metrics, and assessing whether results are genuine or noise.
Strong SQL and data warehouse fluency, such as Snowflake, with the ability to perform cohort and funnel analysis independently.
Comfort using AI agents to build and test software and draft and check analytical work, together with the judgment to detect subtle errors.
High tolerance for ambiguity and willingness to work on problems without an established playbook.
Practical ability to evaluate AI-generated output for suitability before it ships.

Nice To Haves

Direct experience integrating identity verification, KYB/KYC, or fraud and risk providers.
Fintech-adjacent experience handling credit, payment, or other sensitive financial data responsibly.
Experience in a high-growth marketplace or fintech environment with similar account lifecycle complexity.
Familiarity with workflow/orchestration tools such as Temporal or AWS Step Functions, or event-streaming platforms such as Kafka.

Responsibilities

Own and evolve backend services for onboarding, verification, activation, and the sign-up-to-purchase funnel.
Design and build event-driven, workflow-orchestrated systems that continuously evaluate account lifecycle states and automatically trigger appropriate actions.
Integrate third-party identity verification, KYB/KYC, and fraud/risk providers, ensuring integrations are resilient, monitored, and fail safely.
Handle credit and payment data responsibly in personalization and reactivation logic.
Design and run experiments, including defining guardrail metrics and evaluating whether results are meaningful or noise.
Write SQL and work directly in the data warehouse to conduct cohort analysis and diagnose activation, churn, and funnel problems.
Investigate and help define ambiguous problems, such as credit utilization gaps or declines in signup-to-purchase conversion.
Use AI agents to accelerate building and testing funnel and lifecycle services, and review AI-assisted work carefully.
Use AI to draft and check analytical queries, then verify results before they inform decisions.
Critically evaluate AI-generated messaging, reactivation copy, and churn-cause suggestions before they are used.