2D/3D Web & Mobile Character Developer: Interactive Animated Avatar (Rive / Spine / Canvas)

I am looking for an experienced interactive animator/developer to create an expressive, cartoon-like digital character for web and mobile platforms (similar in style and interactivity to Microsoft CoPilot's Mico or Duolingo's Lily). The character will act as an interactive conversational agent. It must feature real-time animation states (blinking, eyebrow movement, lip-sync/speaking visuals) and integrate with audio output to interact dynamically with users. Core Responsibilities Character Development & Rigging: Design or integrate a 2D/3D cartoon character with interactive facial blendshapes/rigs (eyes, eyebrows, mouth states). State & Lip-Sync Animation: Implement dynamic visual states (idle, listening, thinking, speaking) and sync mouth movements with text-to-speech (TTS) audio output (visemes or amplitude-based sync). Cross-Platform Integration: Build a performant runtime component for Web (React/HTML5 Canvas/Three.js/Rive) with architectural compatibility for future native mobile integration (React Native, Flutter, or iOS/Android native SDKs). Conversational Loop Logic: Connect the visual component to voice/text input (STT) and dynamic LLM/API responses for real-time visual feedback during user interactions. NOTE: this capability needs to be presented as a demo - with the animation character - for the project/milestone to be signed-off and closed. Technical Requirements Animation Runtimes: Experience with Rive, Spine 2D, Three.js / WebGL, or Lottie. (Rive preferred for lightweight vector performance and real-time state machines across Web/Mobile). Audio & Viseme Sync: Proficiency in driving facial animations via audio playback, Web Audio API, or viseme data markers (e.g., Azure Speech, ElevenLabs, Amazon Polly). Frontend Tech Stack: JavaScript/TypeScript, HTML5, React/Vue, CSS/Canvas. API Integration: Familiarity with integrating Web Speech APIs or third-party Speech-to-Text (STT) and Text-to-Speech (TTS) services. Preferred Qualifications Prior portfolio demonstrating interactive avatars, conversational UI, or web-based game characters. Experience deploying cross-platform animation assets via React Native or Flutter. Application Instructions To apply, please submit: Links to relevant portfolio pieces or live demos showing interactive web animations or rigged characters. Your recommended tech stack/tooling for handling cross-platform web and mobile character animation efficiently. Estimated timeline and milestone breakdown.