The Senior Software Engineer II will work on AI-driven solutions, developing and deploying scalable applications while mentoring engineers and collaborating with cross-functional teams.
About Extend:
Extend is revolutionizing the post-purchase experience for retailers and their customers by providing merchants with AI-driven solutions that enhance customer satisfaction and drive revenue growth. Our comprehensive platform offers automated customer service handling, seamless returns/exchange management, end-to-end automated fulfillment, and product protection and shipping protection alongside Extend's best-in-class fraud detection. By integrating leading-edge technology with exceptional customer service, Extend empowers businesses to build trust and loyalty among consumers while reducing costs and increasing profits.
Today, Extend works with more than 1,000 leading merchant partners across industries, including fashion/apparel, cosmetics, furniture, jewelry, consumer electronics, auto parts, sports and fitness, and much more. Extend is backed by some of the most prominent technology investors in the industry, and our headquarters is in downtown San Francisco.
About The Role:
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.
What You'll Do:
- Tackle ambiguous, cross-system problems spanning all aspects of fulfillment and servicing
- 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
What We're Looking For:
- 8+ years of full-stack experience
- Proven track record building distributed, cloud-native applications, with hands-on serverless experience
- Demonstrated experience shipping AI/LLM features to production
- Strong instincts for API design 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
Estimated Pay Range: $171,000 - $198,000 per year salaried*
* The target base salary range for this position is listed above. Individual salaries are determined based on a number of factors including, but not limited to, job-related knowledge, skills and experience.
Life at Extend:
- Working with a great team from diverse backgrounds in a collaborative and supportive environment.
- Competitive salary based on experience, with full medical and dental & vision benefits.
- Stock in an early-stage startup growing quickly.
- Generous, flexible paid time off policy.
- 401(k) with Financial Guidance from Morgan Stanley.
Extend CCPA HR Notice
Similar Jobs
Fintech • Software • Financial Services
Design, build, and deploy scalable, containerized backend systems in Scala for a low-latency trading platform. Architect and maintain microservices on Kubernetes, integrate market data feeds, implement monitoring/logging, and collaborate cross-functionally to deliver resilient production services. Own projects end-to-end from design through deployment and maintenance.
Top Skills:
Distributed SystemsGoogle Cloud PlatformKubernetesMicroservicesScala
Artificial Intelligence • Cloud • Computer Vision • Hardware • Internet of Things • Software
Design, build, and operate authentication and authorization systems for millions of users and devices. Drive IAM strategy for AI agents, implement secure, standards-based solutions, mentor engineers, partner with cross-functional teams on security, compliance, and scalable distributed system architecture.
Top Skills:
Ai AgentsAWSAzureGCPGoJavaJwtOauth2OidcPythonSAMLSession ManagementSsoZero-Trust
Fintech • Machine Learning • Payments • Social Impact • Software • Financial Services
Design and implement scalable, maintainable backend systems and AI-powered workflow automation. Collaborate with product, design, and AI teams, own technical roadmap, resolve architectural challenges, mentor engineers, and ensure reliability through testing and operational excellence.
Top Skills:
AWSDockerFaissGeminiGoKubernetesLangchainPineconeReactTypescriptWeaviate
What you need to know about the Seattle Tech Scene
Home to tech titans like Microsoft and Amazon, Seattle punches far above its weight in innovation. But its surrounding mountains, sprinkled with world-famous hiking trails and climbing routes, make the city a destination for outdoorsy types as well. Established as a logging town before shifting to shipbuilding and logistics, the Emerald City is now known for its contributions to aerospace, software, biotech and cloud computing. And its status as a thriving tech ecosystem is attracting out-of-town companies looking to establish new tech and engineering hubs.
Key Facts About Seattle Tech
- Number of Tech Workers: 287,000; 13% of overall workforce (2024 CompTIA survey)
- Major Tech Employers: Amazon, Microsoft, Meta, Google
- Key Industries: Artificial intelligence, cloud computing, software, biotechnology, game development
- Funding Landscape: $3.1 billion in venture capital funding in 2024 (Pitchbook)
- Notable Investors: Madrona, Fuse, Tola, Maveron
- Research Centers and Universities: University of Washington, Seattle University, Seattle Pacific University, Allen Institute for Brain Science, Bill & Melinda Gates Foundation, Seattle Children’s Research Institute
