Founding Engineer
Hybrid (San Francisco, CA, US)$150k - $200k + equityFull-timePosted 4mo ago
About the role
Founding engineer role at Klavis AI, a YC-backed startup building high-quality agentic and coding data for frontier AI post-training. Role involves building systems and datasets to enable training of coding agents and AI tools, with ownership from design to production in a founder-level startup environment.
Responsibilities
- Build high-quality long-horizon coding datasets for frontier AI post-training
- Create coding tasks, hidden tests, gold solutions, rubrics, dockerized environments, and agent trajectories
- Design realistic software engineering workflows across terminals, repos, APIs, databases, and developer tools
- Use LLMs and coding agents aggressively to accelerate engineering and data production
- Build infrastructure for data generation, environment orchestration, verification, evaluation, and QA
- Work with human experts to define difficult, realistic, and verifiable coding tasks
- Design agentic tool-use workflows across SaaS apps, APIs, MCP servers, and external tools where needed
- Turn ambiguous customer needs into reliable, scalable data products
Qualifications
- 3+ years of professional software engineering experience
- Extremely strong with LLMs, coding agents, and AI-assisted engineering workflows
- Build across Python, TypeScript, shell, Docker, Git, APIs, databases, and modern dev tools
- Strong taste for realistic long-horizon coding tasks, test design, agent workflows, evals, and edge cases
- Care deeply about correctness, verification, reproducibility, and data quality
- Move fast without accepting sloppy work
- Want ownership, ambiguity, and intensity of joining at the founding stage
Skills
Required:PythonMachine LearningLLMsAI AgentsShellDockerGitAPIsDatabases
Nice to have:TypeScript
Last updated Aug 26, 2026. Interested? Apply on the company site.
About Klavis AI
Open source MCP integration platform for reliably tool use at scale.
Klavis AI is Open source MCP integration platform that let AI agents use tools reliably at any scale. Our API provides hosted, secure MCP servers, eliminating auth management and client-side code. Co-founder Xiangkai Zeng co-authored the Gemini paper and pioneered the tool calling infrastructure for Gemini. https://www.klavis.ai/
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