Staff Software Engineer, Backend

About Us

XOXO is a research lab building the interface of intelligence for everyday life. We're a stealth team of hardcore engineers, designers, and researchers discovering solutions to novel problems impacting life outside work.

With a recent breakthrough across infrastructure, architecture, and the model layer, we’re hiring serious builders to develop the interface and application layer that will bring our vision to life.

About the Role

We’re hiring an experienced backend engineer to design, build, and operate production-grade backend systems. This role is for someone who is deeply fluent in cloud infrastructure, distributed systems, observability, and data persistence, where testing and stability are at the core of how you operate.

You’ll take full ownership of backend projects from concept through production launch, with a focus on performance, reliability, infrastructure efficiency, and security throughout the development lifecycle.

What You’ll Do

• Build and operate backend services and distributed systems in production on AWS or GCP.

• Design data storage and retrieval using the right mix of vector, OLAP, SQL, NoSQL, cache, and search systems.

• Implement and run observability: monitoring, logging, tracing, and alerting to keep systems healthy and performant.

• Design and implement comprehensive test harnesses that cover deployment and runtime failure scenarios.

• Own backend projects end-to-end: complex feature development, CI/CD + Terraform, stability, and security.

Skills & Qualifications

Minimum qualifications:

• Deep, hands-on experience designing and operating distributed systems in production.

• Expert experience deploying, managing, and scaling applications on AWS or GCP.

• Strong observability practice: monitoring, logging, tracing, and alerting.

• Broad knowledge of data persistence systems (Vector, OLAP, SQL, NoSQL,cache, Search).

• Exceptional algorithms and data structures experience, with a focus on retrieval and performance optimization.

• Demonstrated ability to design and implement test harnesses that cover deployment and runtime failure scenarios.

• Strong ownership: able to take projects from concept to production independently.

Preferred qualifications — we encourage you to apply if you meet some but not all of these:

• Hands-on experience with CI/CD and Infrastructure as Code (Terraform).

• Track record of prioritizing stability and preventing errors in production systems.

• Ability to make architecture decisions that balance performance and infrastructure cost-efficiency.

• Consistent application of security best practices throughout the development lifecycle.

A link to relevant code, technical writing, or project work is strongly encouraged.

Logistics

• Location: San Francisco, CA (on-site)

• Compensation: $250k-$500k expected salary with 1% to 5% equity depending on background.

• Benefits: Top tier health, dental, vision benefits, and many other perks.