Staff Back-End Engineer, Commerce

San Francisco, United StatesHybrid

Responsibilities

Architect: Define the multi-quarter technical roadmap for Commerce domains (payments, payouts, billing) along with the engineering manager and architects - driving strategy, addressing tech debt, and evolving scalable system architecture, APIs, and data models for financial correctness.
Tech Lead: Lead complex, cross-team technical initiatives involving Taskrabbit, Stripe, and Sovos.
Collaborate across engineering, finance, and product to align on architecture and manage dependencies.
Own complex production debugging and drive systemic fixes.
Improve incident response and automate reconciliation workflows.
Champion Spec-Driven Development (SDD) : Lead the adoption of Spec-Driven Development (SDD) with AI tools, ensuring engineers consistently turn well-defined specs into robust Ruby on Rails implementations and comprehensive RSpec unit and integration tests. Requirements:

Operational Excellence: Elevate reliability and observability (Datadog, Kafka) for money-flow systems.
Multiplier: Serve as a Ruby on Rails subject-matter expert, champion high-quality testing (RSpec) for financial systems, mentor engineers, and produce durable technical documentation.
Deep expertise in building and evolving large Ruby on Rails applications.
Strong SQL and data modeling for financial use cases (Postgres, Snowflake). Hands-on
experience with async/event-driven systems (Kafka) handling financial data(idempotency, ordering).
Mastery in production debugging, modernization, and RSpec testing for financial correctness.
Experience in fintech, billing, or e‑commerce domains. Hands-on AI tools
experience with Claude, Augment CLI et al
Experience with accounting and financial reconciliation flows, audits, or compliance-sensitive systems.

7+ years professional backend engineering, with demonstrated Staff-level impact (leading complex domains, influencing multiple teams).