What is Sekai?

Sekai is building the TikTok for interactive mini-apps. Users scroll a feed of playable content—and they can also create new mini-apps (games, quizzes, interactive stories, utilities) simply by describing what they want.

Why we’re hiring

We’re doubling down on creation quality and reliability. This is a key role with real ownership: the person will run the lane end-to-end and set the technical bar for agent-driven app generation.

Role: Senior AI Agent Engineer / Tech Lead (Coding Agent)

You will own

• Designing and owning the agent runtime and orchestration layer
• Building long-horizon agent workflows: prompt → plan → generate → run/validate → repair → publish
• Developing robust evaluation and quality loops including eval harnesses, regression testing, and failure taxonomy
• Designing model strategies including routing, benchmarking, reliability improvements, and cost/latency optimization
• Creating debuggable agent systems with tracing, metrics, alerts, and observability

We’re looking for

• have more than 5 year full-time working experience
• Have experience building agentic systems involving tool use, orchestration, retry/repair loops, and context management
• Are comfortable working with modern agent frameworks, such as
• LangChain, LangGraph, Google ADK, Pi-mono, or Vercel AI SDK
• Are strong engineers in Python or TypeScript
• Have experience shipping and operating production systems
• Have strong product instincts and can translate user experience goals into system design decisions

Bonus points

• Built a coding agent, devtool, IDE assistant, or code generation pipeline
• Experience building evaluation frameworks (automated scoring, regression suites, release gating)
• Experience designing MCP-style tool protocols or robust tool interfaces for LLM systems

Compensation & benefits

• Compensation: competitive base salary + equity
• Health coverage: we cover full health insurance