MultiApps (ucall.me) - Monorepo Overview

This repository hosts a multi-app platform under one domain. The backend is the central gateway for auth, access control, and app delivery. The landing UI is a Svelte app. Apps are organized under /apps and are served via /apps/<slug>.

Important rules:

Svelte only for apps (no SvelteKit, no TypeScript, no React).
Svelte views are presentational only; logic and validation are server-side.
Every change must be documented in AblaufProtokoll.md.

Architecture

Core components

Backend gateway: backend/server.js
- Central entrypoint for API and app delivery.
- Auth, app access checks, and routing live here.
Database: MongoDB
- Core collections: users, apps, translations, highscores, subscriptions.
- Translations live in DB (no translation folders in active code).
Landing UI: frontend-svelte
- Dynamic app listing (DB + registry).
- Presentational only; no client-side validation logic.
App registry (SSOT): appRegistry.js
- Slugs, names, embedded flags, dev ports.

Routing and app delivery

Apps are delivered under /apps/<slug>.
Short URL and QR redirects:
- /s/:slug -> short URL redirect
- /q/:slug -> QR code redirect
Dev proxy mapping is derived from the registry (backend/config/appDevProxy.js).

Tech stack

Node.js + Express (backend/)
Svelte (landing and active apps)
MongoDB (local dev default)
Vite for Svelte dev/build

Project structure

backend/           Central API + app gateway (Express)
frontend-svelte/   Landing UI (Svelte)
apps/              Individual apps and concepts
database/          Legacy routes/models (see notes below)
shared/            Shared utilities
scripts/           Dev orchestration

Apps in /apps

Registry entries (from `appRegistry.js`)

These are the active slugs and their current folder status:

Registry slug	Folder / source path	Notes	Migration status
`qrcode`	`apps/qrcode`	Svelte app (Vite)	Svelte-only
`shortener`	`apps/shortener`	Svelte app (Vite)	Svelte-only
`2048-plus`	`apps/2048-plus`	Svelte app (Vite)	Svelte-only
`wordle-plus`	`apps/wordle-plus`	Svelte app (Vite)	Svelte-only
`fruits-plus`	`apps/fruits-plus`	Svelte app (Vite)	Svelte-only
`blood`	`apps/blood/WebApp`	Svelte WebApp used in `scripts/dev.js`; `apps/blood` also contains a Next.js app (legacy)	Partial (legacy present)
`wasserreminder`	`apps/wasserReminder/WebApp`	Svelte WebApp used in `scripts/dev.js`; folder also includes server/json tools	Partial (non-Svelte assets/tools present)
`wordclock`	`apps/WordClock/WebApp`	Svelte WebApp used in `scripts/dev.js`; folder also includes static HTML/JS	Partial (legacy static app present)
`grammarai`	`apps/grammarAi/WebApp`	Svelte WebApp used in `scripts/dev.js`; `apps/grammarAi` also contains React/TypeScript (legacy)	Partial (legacy present)
`qrshortdoorbell`	`apps/QrShortDoorBell`	Documentation only (no Svelte app yet)	Not started
`games`	`apps/games`	Documentation only (no Svelte app yet)	Not started
`calculators`	`apps/calculators`	Static HTML/JS (no Svelte app yet)	Needs migration

Legacy / conceptual folders (not in registry or non-compliant stacks)

These folders exist but are not in the registry and/or use non-Svelte stacks. They must be migrated to Svelte.js (no SvelteKit, no TypeScript, no React):

apps/auction (React/Vite app in root; separate backend; Svelte frontend exists in apps/auction/frontend) - needs migration/cleanup
apps/grammarAi (React/TypeScript in root, separate from WebApp) - needs migration/cleanup
apps/taxiBayTreuhand (Next.js + TypeScript web app, React Native mobile app, plus separate API) - needs migration
apps/blood (Next.js app in root, separate from WebApp Svelte app) - needs migration/cleanup
apps/URL_shorter (Express/Mongoose service, no Svelte app) - needs migration
apps/MadeIn/Projekt (SvelteKit + TypeScript) - needs migration
apps/coffefinder (Svelte app with TypeScript files and SvelteKit-style routes like src/routes/+layout.svelte) - needs migration
apps/MemeCoinToken (static HTML/documents) - needs migration or archiving
apps/platform (documentation only) - needs migration or archiving
apps/naviQuiz (documentation only) - needs migration or archiving

Migration checklist (legacy -> Svelte.js)

Identify the target Svelte entrypoint and remove React/Next/SvelteKit dependencies.
Convert TypeScript files to plain JavaScript where required.
Ensure all client logic is moved server-side; keep Svelte views presentational.
Replace client-side auth/validation with backend APIs and access checks.
Hook translations into DB-only storage (no local translation folders).
Add/update registry entry in appRegistry.js and sync DB (npm run db:sync:apps).
Ensure dev server is added to scripts/dev.js if it needs a port.
Document the migration step in AblaufProtokoll.md.

Development

Prerequisites

Node.js
MongoDB running locally

Install

npm install

Dev start (recommended)

npm run dev

This runs scripts/dev.js which starts:

backend (backend/server.js)
landing (frontend-svelte)
app dev servers for registry apps with devPort (qrcode, shortener, 2048+, wordle+, fruits+, blood, wasserReminder, wordclock, grammarAi)

Logs are written to dev.log.

Useful scripts (root)

npm run dev - full dev orchestration
npm run dev:backend - backend only
npm run dev:frontend - landing only
npm run db:seed - seed apps from /apps
npm run db:seed:users - seed test/admin users
npm run db:sync:apps - sync registry to DB

URLs (dev)

Landing: http://localhost:5173/
API: http://localhost:3000/
Apps: http://localhost:3000/apps/<slug>

Data and access control

Auth uses JWT (httpOnly cookie supported).
App access is enforced server-side.
Admins are treated as full access.
Highscores and translations are stored in MongoDB.

Deployment (summary)

Use a reverse proxy (e.g. nginx) in front of the Node server with HTTPS.

Documentation

Rules and constraints: rules.md
Architecture and change log: AblaufProtokoll.md
Product requirements: PRD.md
Baseline plan: Plan.md

README