Automation, Software & Process Work · since MMXX

Justin Hennies

I automate, improve and build - so that the things your business needs to run keep running, without anyone pushing them. From small scripts to full web applications.

Start a project See the works
  • Backend & APIs
  • Web apps
  • Automation
  • Computer Vision
  • E-Commerce

Selected Works

I. Index
01

Automated invoicing & management

With FTP integration and price calculator

  • Invoice generation with sequential numbering and PDF export
  • Parameter-based price calculation and open-item management
  • Automated FTP upload to a target system
BackendPDFFTPAutomation
02

Inventory sync & order processing

Product and stock sync between shops and ERP

  • Keeps inventory, prices and variants in sync across shops and ERP
  • Order import and export via API, CSV and FTP with status updates
  • Resilient error handling with retry, monitoring and structured logs
ShopifyeBayWooCommerceETL
03

AI model training for e-commerce

Product classification and similarity search via custom models

  • Built a training-data pipeline for product information in text and image
  • Training and evaluation of classification and embedding models
  • Deployed as a microservice with REST API and batch inference mode
PythonDeep LearningE-CommerceREST API
04

Image database matching with VGG16

Similarity search across large image collections

  • Compare images against a large database with top-N matches
  • Feature extraction with VGG16, efficient indexing and ranking
  • Extensible with semantic filters and report generation
pic2search.com
Computer VisionVGG16Indexing
05

SkinFolio - CS2 skin portfolio tracker

Own product: real-time P&L, cost basis and multi-market pricing for CS2 inventories

  • Real-time P&L across the whole skin inventory, with per-purchase cost basis and sales tracking
  • Price aggregation across Steam, Skinport, CSFloat and SkinBaron via an hourly snapshot cron
  • Astro SSR on Cloudflare Workers, Firebase Functions and Firestore, KV caching for zero-read public pages
skinfolio.net
AstroFirebaseCloudflareOwn Product
06

Web monitoring & evidence capture

Data collection, matching, and automated reports

  • Scrapers to archive and version website content and search results
  • Database matching and notifications on hits
  • Automated report generation for internal review processes
ScrapingMonitoringAutomation

Some projects are confidential. Details and demos on request - I'd rather show how a solution actually looks than how it sounds.

The Workshop

II. Services
What I do

I write software for people who mean business - no demos, no half measures.

  • Process & automation

    • Automate recurring workflows, connect what's already there
    • Scraping, monitoring, reports on demand

  • Backend & APIs

    • REST APIs, auth, data persistence in Python
    • Integrations via FTP and external services

  • Web development

    • Fast, accessible websites and web apps
    • Clean implementation, SEO-friendly, maintainable

  • E-Commerce & AI

    • Shops, payment and shipping integrations
    • Model training, image search, data matching

Tools & Stack

III. Instruments

Frontend

  • Vanilla JS, semantic HTML
  • Performant CSS, progressive enhancement
  • Accessibility first

Backend

  • Python · FastAPI · Flask
  • REST, auth, background jobs
  • Test-driven development

Data

  • PostgreSQL, Redis caching
  • ETL pipelines and migrations
  • Clean schemas

Operations

  • CI/CD, containers, infrastructure as code
  • Observability: logs, metrics, tracing
  • No mystery, just craft

About me

IV. Principal

I have been building solutions that deliver real value for several years - from performant web apps to automation, AI-driven data matching and custom system integrations. Pragmatic, test-driven, maintainable.

Skills

  • Backend, REST APIs, databases
  • Frontend & UI integration
  • Scraping, automation, ETL
  • Computer vision, model training
  • E-commerce integrations

How we work

V. Method

i.

Intro

A short call. Clarify goals and scope, get a first assessment - no sales pressure.

ii.

Proposal

An outline of solution, scope, timeline and budget - pragmatic and realistic, no castles in the air.

iii.

Build

Iterative, test-driven and transparent. Regular checkpoints, no surprises at the end.

iv.

Handover

Documentation, handover and - if wanted - ongoing development or support afterwards.

Get in touch

VI. Correspondence

A good project
begins with a conversation.

Interested in working together, or have questions about a specific project? Drop me a line - a few sentences of context is all I need to get started.

Straight to my desk

info@justinhennies.de

Send email