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Web Development

I specialize in developing custom websites and web applications using, but not limited to, the stack listed below.
Most applications can be build and run as SaaS Software-as-a-Service that can be leased by clients.

(Technical)
Content Editing & Management

I offer content management and editing services for websites, including formatting and custom CMS Content Management Systems support for platforms such as:

  •  Typo3
  •  WordPress
  •  Joomla
  •  Drupal
  •  Wix
  •  Shopify
Scientific Programming

I use Julia and other scientific programming languages to create specialized tools and software for scientific applications. These tools can be provided as a CLI Command Line Interface or e.g. as Jupyter notebooks.
Note: clients can choose whether the software is published as Open Source or not.

System Administration

I can help you with system administration, such as: 

  • server administration, 
  • fully automatic (client) installation (FAI), 
  • cluster management,
  • kubernetes,
  • high performance computing, 
  • parallel computing,
  • and more.
Online Surveys & Data Analysis

I can create and host online surveys using LimeSurvey and provide statistical analysis of the results. Most analysis can be done in Microsoft Excel, which makes it easy for clients to access the results.
Note: for more complex analysis of mostly numeric data, I can provide a custom solution e.g. using Julia.

IT-Support & Consulting

I offer IT support and consulting services to help clients with a range of IT-related issues, including troubleshooting, webhosting and server setup, and finding solutions that meet their specific needs.

(Web) Design

I offer simple design services for both print and web projects.

And More

Upon request, I can provide additional related services in the areas of IT, physics, or general problem solving.

About me

I develope (web-)applications that mostly run as SaaS (Software-as-a-Service).
To create my software I usually use a subset of the stack listed below:

Front End

  • html5 HTML5
  • css3 CSS3
  • javascript JavaScript
  • jquery jQuery

Back End

  • php PHP
  • julia Julia
  • python Python
  • java Java

Database

  • mysql MySQL

DevOps

  • nginx NGINX
  • lamp LAMP Linux-Apache-MySQL-PHP
  • docker Docker
  • kubernetes Kubernetes
  • FAI FAI Fully Automatic Installation

Mobile

  • pwa PWA Progressive Web App
  • android Android
  • flutter Flutter

Other

  • linux Linux
  • bash bash
  • macOS macOS
  • Windows Windows

CONTACT

Use the contact form or write me at 

 info [at] xefli.de

Address

Friedrich-Karl-Str. 91
Köln 50735