Documentation improvements

docs/index.md

@@ -0,0 +1,40 @@
+# Student Database – Developer Documentation
+
+The Student Database is a Java-based server application designed to
+manage and persist student-related data for educational institutions.
+
+It provides:
+- A database-backed backend for managing students, classes, subjects,
+  and related entities
+- A web interface for students and teachers
+- A command-line interface for administrative tasks
+
+This documentation is intended for developers who want to understand,
+maintain, or extend the backend system or the web interface.
+
+## Scope of this documentation
+
+This documentation focuses on:
+- Backend and frontend architecture and design decisions
+- Package responsibilities and boundaries
+- Extension points and integration guidelines
+
+End-user documentation (usage of the web interface or CLI commands)
+is maintained separately in the project Wiki.
+
+## Technology Stack
+
+- Java 17
+- Gradle
+- SQLite (via JDBC)
+- Custom HTTP server and templating
+
+## Getting Started
+
+- Backend Architecture Overview: architecture/backend-overview.md
+- Application Startup Flow: architecture/startup-lifecycle.md
+- Package Responsibilities: packages/
+
+## Presentation
+
+- [Presentation for teachers](presentation_april.pdf)

docs/packages/toplevel.md

@@ -1,5 +1,8 @@
 # Toplevel Package
 
+In the top level package `de.igslandstuhl.database`, you can find the entry point of 
+the application, and registries that are available everywhere on the backend.
+
 ## Application (Singleton)
 - Entry point for application startup
 - Prepares environment