Software

Alongside my research I work part-time as a software developer at Auto-Koch GmbH & Co. KG. Over the past years my main project there has been KoKi, an in-house system for managing customer and vehicle data that I designed, built and continuously expanded, and which is in daily production use across the dealership’s branches.

KoKi: Customer & Vehicle Management

KoKi is a web-based business application I have been developing since 2019 for the day-to-day operations of a car dealership group. It keeps customer and vehicle records together, supports the service workflow around inspections (TÜV) and maintenance, and automates the recurring communication and paperwork around them. The system is multi-tenant across the group’s five branches and is used in production every day.

Key Features

Combined customer and vehicle records, synchronised daily from the dealership management system
Vehicle inventory overview (days in stock, registration, status)
Appointment and service management with calendar view
Automated appointment reminders via SMS and email
Template-based PDF generation (e.g. customer letters)
Internal staff chat and direct SMS/email to customers
User management with role-based permissions and a full audit log
Statistics and dashboards computed from the database

Technical Highlights

Custom single-page application in vanilla JavaScript, no front-end framework
Real-time client-server architecture over WebSockets rather than a REST API, with all application logic server-side
Live updates pushed via PostgreSQL LISTEN/NOTIFY triggers
Daily automated synchronisation with the dealership management system
Standalone background services for data sync and automated reminders
Server-side PDF generation from templates using headless Chromium
JWT-based authentication, bcrypt password hashing and role-based access control
Parameterised SQL throughout (no ORM), guarding against SQL injection

Technologies

Frontend

HTML5

CSS3

JavaScript

Backend

Node.js

WebSocket

PostgreSQL

Tooling

Puppeteer

JWT & bcrypt