>2U Postal
A sealed time-capsule postal platform to compose heartfelt messages to your future self, protected by AES-256-GCM client-side encryption and delivered via automated cron jobs.
// specifications
Technical Architecture Matrix
// blueprint
Detailed Engineering Breakdown
2U Postal is a digital time-capsule postal platform that allows users to compose heartfelt letters to their future selves. Letters remain locked, encrypted, and unreadable until a chosen future delivery date—whether six months, a year, or a decade later.
//Core Features:
▸Distraction-Free Letter Studio: Compose rich personal reflections or upload scanned photos of handwritten notes.
▸AES-256-GCM Privacy Encryption: All letter contents, titles, and scanned image URLs are cryptographically encrypted before being stored in the database, ensuring zero plaintext access.
▸Sealed Time Capsules: Letters remain locked until their scheduled delivery date, featuring live countdown timers and custom wax seal monograms.
▸Automated Email Dispatch: Integrated with Vercel Cron (/api/cron) to dispatch unlocked letters directly to the author's inbox via Resend or Gmail SMTP.
▸Authentication & Quotas: Managed user authentication via Clerk with in-transit quota management.
▸Editorial Aesthetics: Minimalist postal design system built with DM Serif Display, vintage postmarks, and paper-lined textareas.
//Security & Architecture:
▸Zero Clear-Text Storage: Every encrypted record utilizes a fresh 12-byte initialization vector (IV) and 16-byte authentication tag for tamper resistance.
▸Server-Side Decryption: Decryption only occurs during scheduled cron delivery or authenticated user requests via TanStack Start server functions.
// stack