Small Kotlin Multiplatform app built to learn KMP, with shared UI and logic across Android, Web, and the server. (done with the Claude help)

ReceiptsArchiver

A receipt archiver for Slovak eKasa fiscal receipts. Scan the QR code printed on a shop receipt, and the app looks it up via the eKasa API, saves it, and shows it in a searchable list with itemized detail — from Android or a browser.

Modules

• core — shared API DTOs and the Ktor HTTP client used by both frontends.
• app/shared — the Compose Multiplatform UI (list, detail, scanner screens) shared between Android and Web.
• app/androidApp — Android entry point; the only target with the QR scanner.
• app/webApp — Kotlin/Wasm entry point, compiled to a static web bundle.
• server — Ktor backend: REST API, eKasa client, SQLite persistence via Exposed, and static hosting of the web bundle.

Running locally

• Server: ./gradlew :server:run (port 8081)
• Web app: ./gradlew :app:webApp:wasmJsBrowserDevelopmentRun (port 8080)
• Android app: ./gradlew :app:androidApp:assembleDebug (or run from Android Studio; point API_BASE_URL in MainActivity.kt at your server's address,

Server configuration

The server reads its configuration from environment variables:

Variable	Default	Description
PORT	8081	HTTP port
HOST	0.0.0.0	Bind address
DB_PATH	/data/receipts.db	SQLite database file
EKASA_BASE_URL	https://ekasa.financnasprava.sk	eKasa API base URL
WEB_DIR	/app/web	Static web bundle directory served at /

The API and the web UI are served on the same port — /api/* routes handle the REST API, and everything else falls back to the static web bundle (with SPA-style fallback to index.html).

Docker

Build and run as a single container:

docker build -t receipts .
docker run -p 8080:8080 -v receipts-data:/data receipts

The image bundles both the server and the pre-built web app; receipts persist in the /data volume.