Front-End Developer at Braintrust

Job Description

Job Description

🚀 About Mini Studio AI

Mini Studio AI is an early-stage startup pioneering the future of animation. We’re building a

magical storytelling engine powered by generative AI to create deeply personalized, emotionally

resonant animated content for kids — think Pixar meets GPT. From personalized cartoons and

social-emotional learning stories to interactive kids’ content, we’re redefining what animation can

be.

We’re a small, fast-moving team of creatives and technologists with a big mission: to make

every child feel seen, understood, and inspired. Backed by a16z and other top investors, we’re

growing fast and looking for ambitious collaborators to help us build the next chapter of

storytelling.

🎯 What You’ll Do

As our Front-End Developer, you’ll play a central role in building and optimizing our

GenAI-powered video editing platform. You’ll work in a modern monorepo setup, integrating

real-time features, browser-level video optimization, and cutting-edge AI interfaces to deliver

magical user experiences.

Key Responsibilities

Firebase Specialist: Build scalable and performant services using Firestore,

Authentication, Cloud Functions, and Firebase PubSub. Optimize queries and manage

hotspot issues.

Media & Video Optimization: Improve browser-level video performance, handle media

metadata efficiently, and ensure seamless video playback.

Remotion / Video Editor Experience: Work on or contribute to web-based video editors

using tools like Remotion or equivalent.

State Management & Data Integration: Manage complex app state with XState or

Zustand, and use GraphQL for structured, high-performance data communication.

AI & GenAI Integrations: Build interfaces powered by Vercel AI SDK and other LLM

tools, including chat-based experiences and creative automation.

Monorepo Collaboration: Work confidently in a monorepo environment, managing

dependencies across shared packages and collaborating across teams.

Real-time & Local Performance: Implement strategies for real-time interactions and

local caching to boost responsiveness and efficiency.

🧠 What We’re Looking For

Strong background in modern JavaScript/TypeScript, React, and media-centric

front-end development.

Solid understanding of Firebase internals and real-world architecture.
Experience optimizing for video performance and media asset handling.
Ability to write modular, testable, maintainable code with a clear structure.
Strong collaboration skills and a proactive, problem-solving mindset.
Enthusiasm for working on ambitious, experimental products at the intersection of

creativity and AI.

🌟 Why Join Us

Help invent the future of creative storytelling and interactive video.
Collaborate in a nimble, mission-driven team backed by a16z.
Build a meaningful product that delights and inspires kids.
Take ownership in a startup where your work will directly shape the product.
Equity, early-stage upside, and creative input from day one.