Tesana is an AI game-building platform that lets anyone create high quality games through natural language.

We are building our own AI game engine called Atomos, that manages game building end-to-end and agents, tools, and infrastructure required to take a game from an idea to a working product. This includes code generation, worldbuilding, gameplay systems, visual creation, debugging, evaluation, and long-running autonomous build loops.

Joining Tesana means working at the edge of AI-assisted game development and helping define how games will be created in the future.

Role Description

As a Full-Stack Engineer at Tesana, you will build and improve the systems that power our AI game-building platform.

You will work across the stack, from polished creator-facing interfaces to backend infrastructure, model orchestration, agent systems, and real-time game-building workflows. You will ship product quickly, work directly with the founders, and take ownership of major features from idea to production.

You should be deeply familiar with the current AI development ecosystem. You use tools such as Cursor or Claude Code daily, understand how to build effective agent loops, and know how to work across different models and providers using platforms such as OpenRouter.

You will help us design systems where AI agents can plan work, write and modify code, inspect results, identify failures, and continue iterating autonomously over long-running tasks.

Daily responsibilities include:

• Building full-stack product features from concept to production
• Developing intuitive interfaces for creating, editing, and testing games
• Designing APIs, databases, and scalable backend services
• Building agentic workflows that plan, execute, evaluate, and iterate
• Integrating and routing between multiple AI models and providers
• Developing evaluation systems for code quality, visual output, and gameplay
• Improving the speed, reliability, and cost of AI-generated builds
• Debugging complex issues across models, agents, infrastructure, and product
• Working closely with product and design to ship improvements quickly
• Contributing to technical architecture and engineering standards

This is a full-time, hybrid role based in San Francisco, CA and/or remote.

Qualifications

• Strong full-stack engineering ability across frontend and backend development
• Previous startup experience
• Advanced proficiency with TypeScript and modern web frameworks such as React, Next.js, or similar
• Experience building reliable APIs, backend services, databases, and production infrastructure
• Strong product judgment and the ability to build polished user experiences
• Daily experience with AI coding tools such as Cursor, Claude Code, Codex, or similar
• Hands-on experience building agent loops, tool-calling systems, or autonomous workflows
• Familiarity with model APIs and routing platforms such as OpenAI, Anthropic, Gemini, and OpenRouter
• Understanding of prompt design, context management, structured outputs, tool use, and model evaluation
• Ability to choose models based on intelligence, speed, reliability, and cost
• Experience working with streaming responses, asynchronous jobs, queues, and long-running processes
• Ability to write clean, maintainable, secure, and well-tested code
• Comfortable moving quickly in an early-stage startup with limited structure
• High ownership and willingness to solve problems outside a narrowly defined role
• Strong written and verbal communication skills

Experience with game engines, procedural generation, multiplayer systems, WebGL, Three.js, or AI-generated visual content is a strong plus.

• A computer science degree is welcome but not required. We care more about what you have built, how quickly you learn, and how effectively you use modern AI tools to ship exceptional products.