Handshake
Senior Software Engineer, Annotations
$208K–$260K
San Francisco, CA · On-site · Senior · Full-time · Posted Oct 2, 2026
- Experience
- 6+ years of software engineering experience building and operating production systems.
About the job
Build and scale software systems and operator tools that manage annotation projects, improve task quality, and support expert workflows for frontier AI companies.
What you'll do
- Build tooling to create, manage, prioritize, and audit annotation projects, including quality-control workflows.
- Develop and deliver reliable full-stack features, leading projects from concept through production and iteration.
- Set technical direction, improve engineering practices, and mentor engineers.
What they ask for
- 6+ years of software engineering experience building and operating production systems.
- Strong proficiency in Node.js, Typescript, React, PostgreSQL, and backend APIs.
- Experience designing scalable, reliable software and owning complex projects through delivery.
- Strong product judgment, communication, and collaborative leadership, including mentoring engineers.
Nice to have
- Experience building workflow, marketplace, operations, or internal-platform software.
- Familiarity with AI/ML data pipelines, annotation systems, evaluation workflows, or human-in-the-loop products.
Pay
$208K – $260K USD base salary
Tools
Node.js, TypeScript, React, PostgreSQL, GraphQL, tRPC
AI focus
Build systems and workflows that power high-quality human data for frontier AI companies, including annotation operations and quality control.
Model-written summary · the original posting is authoritative