# CHIP CENTER Architecture

The portal uses server-rendered Vinext/React on Cloudflare Workers, D1 for relational operational data and R2 for private ECU/TCU binaries. Authentication is delegated to the hosting sign-in layer; authorization remains server-side and checks the user's database role plus resource ownership on every protected action.

Core boundaries are UI components, route/server actions, service rules (credits, assignment, workflow), repositories, and platform adapters (D1, R2, email, payment and realtime). File downloads are never public: an authenticated route validates owner/assigned tuner/admin access, records an audit event, then streams from R2.

Critical credit operations use optimistic wallet versioning inside an atomic batch. A request reserves credit before creation, consumes it on completion, and refunds it on approved cancellation. File metadata stores SHA-256, byte size, MIME, extension, original filename, randomized storage key and version.