Full-Stack Engineer (Frontend-Leaning) at Rim universe in Irvine, CA

Rim Universe is building an AI-native platform for animated and serialized video content creation. Our platform helps creators transform ideas and scripts into structured production workflows, including story development, character creation, episode and shot planning, AI image/video generation, and editing.

We are currently expanding our engineering team and looking for a Full-Stack Engineer to help build our platform. If you're passionate about AI video creation, we'd love to have you join our team and help turn more great stories into amazing videos!

About the Role

Your main focus is the Next.js frontend and the product experience, but you'll also work in the Python backend and the video generation pipeline yourself, so a feature ships end to end, from UI to API.

This is a core role on an early team. You'll take over an existing codebase, help get us through launch and post-launch stability, and have a real say in technical decisions.

Responsibilities

Frontend (60%)

• Design and build the core creator experiences: the AI agent chat and composer, the project pipeline from story to render, the character workspace, and the storyboard and video editing tools.
• Make the node-based generation canvas a joy to use: dragging, connecting, grouping, undo and redo, autosave, and live progress on image and video generation.
• Maintain the Next.js BFF layer: sign-in flows (email code, OAuth, Apple), session cookies and the API proxy.

Backend (40%)

• Maintain and improve the design and versioning of the prompt templates behind our video models, covering shot beats, camera direction, dialogue, sound design and reference-image binding, along with the segmentation logic.
• Review generated videos and agent replies with a critical eye, and turn what you see into better prompts, defaults and validation rules.
• Add the Python / FastAPI endpoints your features need, working with the backend engineer.

Requirements

• Experience with complex, stateful UI, such as editors, canvases, chat or real-time dashboards: optimistic updates, undo history, autosave, streaming data.
• You can take over an existing codebase. You're comfortable reading a large TypeScript monorepo, learning its conventions quickly and making it your own.
• LLM agent and prompt experience. You've written system prompts, tool definitions or structured-output schemas for a production LLM feature, and improved them against real output.
• Hands-on AI video and image generation. You've used models like Seedance, Kling, Runway, Veo or Hailuo and know how to prompt them well.
• Python backend skills. Comfortable writing FastAPI (or similar) endpoints and debugging across the browser, BFF and API.

Nice to Have

• Strong visual taste. You care about layout, type, color and motion, and can explain why one design works better than another. Your portfolio shows it.
• Figma and design-system work.

Rim Universe is moving quickly, so we value engineers who can work independently, solve problems proactively, and communicate clearly with the team. If you're passionate about AI video creation, welcome to join us!

Pay: $30.00 - $40.00 per hour

Benefits:

• 401(k)
• Employee discount
• Flexible schedule

Language:

• Mandarin (Preferred)

Work Location: In person