I am Samuel Gfeller

Application developer, certified by Swiss Federal VET Diploma


Mother tongues: German and French
Comfortable in English

Turnkey Solutions

Able to cover all steps of your projects from brainstorm to design to development and release

Web Development

Specialized in creating small to medium Web applications from A to Z

Working Methodology

A good program is one that users can handle with ease. 

My main focus while creating applications is to make them as simple as only possible for the end user to use. 

When working on the frontend, I put myself in the user’s shoes and try to make the elements that have to be interacted with, as intuitive as I can, free from any unnecessary thing.

Every thing that can be done by the backend of the application, is something that the user doesn’t have to do.

The more the repetitive tasks are taken over by the backend, the more people can focus on other things and free up time.

Frontend Creation

Frontend is the top layer of an application; the part you interact with. 

Its job is to interact with the user and present him the right functionality when he needs it. It will then transmit the inputs to the business logic of the application. 

Backend Development

The backend is the server-side part.

User inputs are being verified, actions triggered and communication is made with the database and other services.


I truly believe that web development is the future. Accessible anywhere with any device without any installation, the advantages are multiple.

PHP is my favourite backend language, and I use MySQL to handle the database.

For the frontend I use the standards HTML, CSS, and JavaScript.


Online portal to manage the process of selling meat and other farm products to customers. 

Customer management & online order system
The administrator can add customers to the system, after which they can order products online. They can only order as long as there is availability.

POS system with barcode scanning
Every second month, customers come buy the products, which are scanned via barcode. A printable invoice is generated.

Invoice creation and management
After the sale, QR bills can be edited, sent via email as an attachment in one click and marked as paid to keep track.

Slim example project

Complete Example Project with Front- and Backend, Automated Testing, Auth System, Permissions, Localization


  • Authentication (login) and authorization (permissions)
  • Account verification and password reset via email link and token
  • Protection against rapid fire and distributed brute force attacks (time throttling and captcha) – docs
  • Localization – English, German, and French
  • Template rendering with native PHP syntax
  • Flash messages
  • An intuitive method for editing values in the browser using “contenteditable”
  • Dark theme
  • Custom error handler – docs
  • Integration testing with fixtures and data providers docs
  • Database migrations and seeding docs

Using the beloved micro-framework
slim in combination of carefully chosen libraries following the Domain Driven Design concept.

Other projects

BrokerStar migrations

Brokerstar is an extensive tool for insurance brokers to handle customers, policies, premiums, claims and more; Gestass and others are competitors. 
I had migrated the content of the old program of the customer (like Gestass) into the BrokerStar database. Gestass and others have very different ways of storing data. The task was basically grabbing the information at the right places, group them, change them and insert into the BrokerStar database.

Merge two databases

Two instances of BrokerStar had to be merged.
Data should not be duplicate, but a lot of times things were partly present in both databases with different primary keys. Only the non-existent ones should be inserted, so all the premiums, policies, invoices etc. had to be relinked with existing data from the target db. 

Psychoanalyse basel

First design for a website that wasn’t for me, but for the psychoanalytical seminar of Basel.

The design had to be simplistic, clean and suiting the healthcare environment.

Quizlet audio converter

This project was made to help out Patricia Ryter for her matura. She has experimented if it is possible to learn a language while sleeping. 

The app extracts the audio files from a Quizlet learn set and converts them into one big file following the specified requirements

Since Quizlet doesn’t provide the audio in an API, I scrape the audio URL from the website. Audios are downloaded, re-encoded so that all have the same bitrate and then assembled following the specified requirements.  

For the media processing I used ffmpeg intensively. I made a detailed code documentation here.

Stream recorder (School project)

Small web app that can record YouTube live-streams while they are playing and save them as mp4 on your computer to watch them later. 

I learned to use ffmpeg as well as youtube-dl and how to display real-time console output to the client with PHP. 

About me.

Samuel Gfeller
Samuel Gfeller

My name is Samuel Gfeller. I’m 23 years old.

I finished my apprenticeship as a computer scientist specialized in application development in July 2020, but there were plenty of things that I still wanted to learn.

In order to focus on my personal development, I left my previous company and have been taking on freelance projects to support myself financially. 

My objective is to have the skills and knowledge necessary to create a highly optimized and efficient web application from start to finish. The example project is the result of my learning in the past 3 years.

Although I am still open for freelance work from time to time, my main focus is creating and marketing an own application in a sector where digitalization can be improved.3