Let's succeed together

Based in Germany, I'm there for you wherever you are!

I would love to help you with my expertise around Ruby, JavaScript, Rails, Vue.js, Docker, Testing, CI... and of course: Matestack. You decide if you just need specific support or if I should build whole applications for you. Just Ruby/Rails or Matestack on top! If necessary, I team up with my partners providing you the ressources you need for your project!

Revenue will be reinvested to fund ongoing Matestack core development, documentation and maintanance.

A team full of mates ready to boost your productivity

Jonas Jabari
Senior Ruby/JavaScript developer, creator and founder of matestack

Nils Henning
Partner, Senior Ruby/JavaScript developer
Pascal Wengerter
Partner, Ruby developer
Andreas Eiselt
Partner, Data scientist and senior Ruby/JavaScript developer

My services around Rails and Matestack:


You'd like to start using Matestack in your business, but need help to get things going and bring your team up to speed? I'm there for you!

Support on demand

You're already using Matestack but need support on specific issues? Just hire me to help you out efficiently!

Development on demand

You want me to join your development team for some time? Great Idea! I'm happy to work on your projects! Just Ruby/Rails or Matestack on top. You decide!


You need me to refactor some bulky legacy views and turn them into future proof, maintainable Ruby code? I love this challenge!

Turnkey applications

Concept and fundig are there, and you "only" need developers/a development team to build the applications? I'm more than happy to do so! Both handover and ongoing support possible. If necessary I can team up with my partner in order to provide more ressources!

Some of Matestack's projects:

Booking system for ABC workspaces

Turnkey application, web app

In 2019, we we're asked to build a booking system for ABC from scratch. Until then the client managed bookings manually. Hundreds of offices in three cities need to be bookable online. Furthermore the client wanted the booking system to be embedded in a unique homepage design, representing the quality of ABC's services.

Due to individual booking constraint, we've created a custom Rails app and implemented all business logic required managing online bookings together with Stripe payment integration. Additionally we've built a member login enabling the customers of ABC to manage their bookings. Furthermore we've implemented an Admin UI, enabling ABC to manage all bookings and offices. The UI layer was built with matestack-ui-core based on the screendesigns coming from our partner W11 GmbH.

Progressive web app for WORKEY

Turnkey application, progressive web app

In 2020, we've created a PWA for WORKEY. Within this app, the user is asked for some feedback concerning the current work environment. The main goal: get to know how to improve the well being of an employee based on feedback.

As it's not to easy to get feedback from employees on a daily basis, the client wanted to offer the employees an installable and enjoyable app. Additionally it was important to remind the employee via push notification to complete the daily questionnaire. We've shipped a PWA based on a Rails application combined with matestack-ui-core.