Senior Software Engineer, Coding

About Handshake

In 2025, we started Handshake AI and built the fastest-growing AI data business in history. We work directly with frontier AI lab researchers to create evaluations, publish benchmarks, and push the boundary of data. We’ve grown from $0 to ~$1B run rate and pay ~$60M to over 30K individuals every month.

About Handshake AI

Human data is the core infrastructure to AI advancement. Frontier AI labs currently improve model capabilities with various data-intensive post-training techniques. We believe that data spend for AI training will increase by 3-5x in the next few years and continue for much longer as models take on new domains. Handshake AI supports all of the frontier AI labs, working on their most complex data at the largest scale.

About the Role

We’re looking for a Senior Software Engineer to help build the systems that power high-quality coding data and evaluations for next-generation AI models.

You’ll work on technically complex projects involving software engineering benchmarks, code review evaluation, agentic coding workflows, and developer-facing tools. You’ll combine strong engineering judgment with hands-on execution, designing reliable systems that enable teams to create, validate, and improve sophisticated coding datasets.

This is an opportunity to shape foundational infrastructure at the intersection of software development and AI. You’ll operate with significant ownership, collaborate closely with engineers and technical program leaders, and help establish the standards and tools that support our fastest-growing AI initiatives.

What You'll Do

• Design, build, and operate scalable software systems for coding evaluation, data generation, and agentic development workflows.
• Develop tools and services that analyze, validate, and improve AI-generated code.
• Build reliable pipelines for code execution, testing, benchmarking, and quality measurement.
• Partner with engineering, research, operations, and customer-facing teams to translate complex requirements into practical systems.
• Drive technical decisions across architecture, APIs, data models, observability, and operational excellence.
• Improve engineering velocity through reusable frameworks, automation, and developer tooling.
• Lead projects from ambiguous problem definition through design, implementation, launch, and iteration.
• Mentor engineers through design reviews, code reviews, and day-to-day collaboration.
• Establish high standards for maintainability, correctness, security, and reliability.

Desired Capabilities

• 6+ years of professional software engineering experience.
• Strong proficiency in Python, JavaScript/TypeScript, Go, or another modern programming language.
• Experience designing and operating production systems with meaningful scale, reliability, and performance requirements.
• Strong understanding of software engineering fundamentals, including testing, APIs, data structures, distributed systems, and observability.
• Experience building developer tools, infrastructure, data pipelines, evaluation systems, or other technically complex products.
• Ability to work effectively in ambiguous environments and break large problems into clear, executable plans.
• Excellent written and verbal communication skills, with the ability to explain technical tradeoffs to both technical and non-technical partners.
• A track record of taking ownership and delivering high-quality results in collaboration with

Bonus Points

• Experience with AI/ML evaluation, coding agents, LLM applications, or developer productivity tools.
• Familiarity with code execution sandboxes, GitHub workflows, CI/CD systems, or benchmark infrastructure.
• Experience working with containerization, cloud platforms, databases, and distributed job orchestration.
• Contributions to open-source software or a demonstrated passion for improving developer tools.
• Experience partnering with research teams or customers to deliver technically rigorous solutions.

Perks

Handshake delivers benefits that help you feel supported—and thrive at work and in life.
The below benefits are for full-time US employees.

🎯 Ownership: Equity in a fast-growing company
💰 Financial Wellness: 401(k) match, competitive compensation, financial coaching
🍼 Family Support: Paid parental leave, fertility benefits, parental coaching
💝 Wellbeing: Medical, dental, and vision, mental health support, wellness stipend
📚 Growth: Learning stipend, ongoing development
💻 Remote & Office: Internet, commuting, and free lunch/gym in our SF office
🏝 Time Off: Flexible PTO, 15 holidays + 2 flex days
🤝 Connection: Team outings & referral bonuses