Chosen Masters AI Mastering B2B API Demo (github.com)

This repo is a drop-in demo for Chosen Masters’ B2B mastering API that recreates the full production workflow: requesting a signed upload URL, submitting a mastering job, and streaming mastered preview “intensities” using the same stack that powers the production dashboard. It’s designed for integrators and ML engineers to validate end-to-end behavior (secure uploads, job orchestration, and preview delivery) and to serve as a reference implementation for embedding mastering into pipelines or dashboards. Technically, the app is a Next.js (App Router) project requiring Node.js 18+ and npm 9+. After npm install, you configure .env.local with your CM_API_KEY (server-side only), PARENT_BASE_URL (defaults to https://chosenmasters.com), and NEXT_PUBLIC_MASTERING_CLOUDFRONT_URL (the public CloudFront endpoint used for streaming previews). Run npm run dev and open http://localhost:3000; interactive docs at /mastering-docs mirror the production flow. The demo’s use of signed upload URLs and a public CDN for preview streaming demonstrates a secure, low-latency pattern for serving mastered outputs to clients while keeping sensitive credentials on the server—useful for teams building scalable, secure mastering pipelines.