Senior Software Engineer II

Extend

1d•Remote

About The Position

We are looking for an exceptional Senior Software Engineer II to join the Extend Fulfillments team, a core pillar driving our company's growth and customer satisfaction. This role offers a unique opportunity to build impactful software used by some of the largest ECommerce and Brick and Mortar merchants in the industry, and directly influencing how our merchants make their customers whole. You’ll partner closely with cross-functional teams in product, design, operations, delivery and the broader engineering organization - contributing significantly to a culture of innovation, continuous improvement, and excellence.

Requirements

8+ years of full-stack experience
Proven track record building distributed, highly available systems on AWS, with hands-on serverless experience
Demonstrated experience shipping AI/LLM features to production
Strong instincts for API design, versioning, idempotency, and backwards compatibility — especially where events drive money movement or fulfillment
A track record of owning large, ambiguous, cross-system initiatives end to end
Proven ability to influence beyond your team — aligning groups, distilling complex ideas for leadership, and pushing back with data
A pattern of mentoring across levels and driving team-wide improvements that outlast any single project
Strong data modeling and context engineering skills that ensure application quality and sound agentic decisioning
Fluency with advanced AI developer tooling, a track record of using it to ship more, and a habit of bringing teammates along
Exceptional communication across product, business stakeholders, designers, support, and engineers
Expert in TypeScript, Node.js, and React

Responsibilities

Tackle ambiguous, cross-system problems spanning all aspects of fulfillment and servicing — refunds, replacements, reverse logistics, and more
Own large features end to end, from design through deployment, release, and monitoring
Deliver scalable, event-driven, AI-native applications that elevate the customer experience
Collaborate with platform teams to enhance overall system architecture
Own the design, implementation, quality and safety of AI/agentic features in production systems
Mentor other engineers across levels through code review, pairing, design collaboration and coaching
Drive adoption of tooling and practices, including AI developer tooling, and codify the habits that make them effective
Advocate for the proactive investments — refactors, observability, upgrades, technology adoption - that enable continuous improvement
Communicate fluently across product, design, solutions, and ops to align outcomes with business goals