Florian Rubel

Senior Fullstack Developer

Cologne, Germany
Experience
Aug 2024 - Sep 2024
2 months

Senior Fullstack Developer

Ivii GmbH

  • Two-month modernization of a management UI for AI-powered cameras monitoring production processes, migrating from React to Vue.js 3 (freelance).
  • Ivii GmbH sells AI-powered camera systems for monitoring production processes.
  • Data sets can be trained with image series and optimized for various components.
  • This project focused on a two-month improvement of the existing user interface.
  • A designer provided the new design.
  • The base was a complex React application to be rewritten in Vue 3 with SFC.
  • The backend consisted of several microservices in C# and Python.
  • My tasks included building the central architecture and configuration of the Vue app.
  • We used Vite as the builder.
  • We also used Pinia, Router, I18n, ESLint, and Prettier.
  • A special feature was using Leaflet.
  • Leaflet is normally for maps but here it drew and displayed detection zones on images.
  • Since no working Vue implementation existed, I wrote a custom integration.
  • I also helped extend the backend, including updating authentication to meet new requirements.
  • Technologies: TypeScript, React, Vue 3, C#, Python, HTML, SVG, Docker, Vite, ESLint, vue-router, vue-i18n, Pinia, Leaflet, SignalR, gRPC
May 2024 - Present
1 year 3 months

Lead Fullstack-Developer

Own commercial project

  • Developing a management project for cinema operators using Vue.js 3 frontend and C# backend.
  • I can share code from this project.
  • I’m still working on this commercial project; I can’t describe its content but can discuss technical details.
  • The backend is C# with .NET 8 MVC, using inheritance and generics to standardize API endpoints and cut code volume.
  • Every controller has a base set of actions and can be extended or restricted.
  • We use Entity Framework.
  • For authentication and authorization, we use Microsoft Identity with a role- and claim-based system applicable to any endpoint.
  • Other features include data shaping, over-posting protection, and data model validation.
  • The frontend is built in Vue.js 3 with TypeScript and mirrors the API’s abstractions in its service layer using classes and generics to easily match standardized endpoints.
  • We may switch to .NET Blazor Pages.
  • Parts of the code and functionality can be presented.
Nov 2023 - Jun 2024
8 months

Lead Frontend Developer

bezahl.de by NX-Technologies

  • Modernizing a fintech product from Vue.js 2 to Vue.js 3 and coaching developers (freelance).
  • The fintech company offers complex payment management for the automotive industry via the bezahl.de platform.
  • We modernized the dealer and customer interface from Vue 2 to Vue 3 with TypeScript.
  • I led the technical architecture and supported the team building the new project.
  • A simple Vue 2 to Vue 3 conversion wasn’t possible due to incompatible dependencies like Buefy.
  • We had to rewrite almost the entire application.
  • We chose SFC for components.
  • We used Vuetify.js and extended it with custom components and styling.
  • At the client’s request we used Pug instead of HTML in templates.
  • The app’s complexity and size required deep familiarization with the existing solution.
  • One of the hardest parts was integrating and correctly typing the existing Node.js/Express REST API.
  • We created themed TypeScript service modules for each API endpoint.
  • We also made API adjustments and extensions.
  • Technologies: TypeScript, JavaScript, Vue 2, Vue 3, Node.js, Express, SCSS, Pug, HTML, SVG, Docker
Jul 2023 - Nov 2023
5 months

Senior Frontend Developer

Rohde & Schwarz Cybersecurity

  • Extending and modernizing a Vue.js-based product for managing and configuring encryption servers (freelance).
  • Rohde & Schwarz Cybersecurity develops hardware solutions to encrypt traffic between corporate networks.
  • I supported the management software’s development and migrated Vue 2 class-based components to Vue 3 setup pattern with TypeScript.
  • The project’s challenge was its immense size; every modernization or refactor required deciding whether to update or rewrite components.
  • The most complex solution I built was centralized form and wizard validation mirroring the API.
  • This mechanism ran throughout the project and provided localized error messages before form submission.
  • All features and bug fixes were thoroughly tested with Vitest.
  • Technologies: Vue.js 3, TypeScript, Vite, SCSS, Node.js, WebSockets, Vitest
Dec 2022 - May 2023
6 months

Lead Senior Fullstack Developer

Talkevent GmbH

  • Modernizing existing front- and backend based on Vue.js and Node.js/Express and switching from JavaScript to TypeScript (freelance).
  • Leading and training developers in new technologies.
  • Talkevent creates chat solutions for banks, insurance companies, and savings banks, offering text, audio, and video chat, co-browsing, whiteboards, screen sharing, and file sharing.
  • All conversations can be archived with personal data removed.
  • I modernized the frontend and backend.
  • The backend in Node.js/Express and MongoDB/Mongoose was migrated to TypeScript and updated to the latest dependencies, with interfaces auto-generated for Mongoose models.
  • The Vue 2 frontend was migrated to Vue 3 with TypeScript and setup pattern, and dependencies were updated.
  • The project’s size required automated scripts for code conversion.
  • Technologies: Vue.js 3, TypeScript, Vite, SCSS, Node.js, Express, Mongoose, MongoDB, Vitest, WebSockets
Dec 2021 - Nov 2022
1 year

Senior Fullstack Developer

Advellence GmbH

  • Building a product data search platform using Vue.js 3, Azure API Management, Azure Functions (C#), Azure Data Factory (freelance).
  • I was hired to build a Vue.js 3 interface for clinics to search items like an e-commerce platform.
  • The client was Advellence GmbH, commissioned by Sana Kliniken AG.
  • I joined as a frontend expert and quickly helped on the backend.
  • Initially the frontend used Vue.js 3 Options API, Vue CLI 4, Vue-I18n, Jest, SASS (BEM), Vue Router, and Vuex.
  • Later we refactored to Composition API with SFC setup pattern, replaced Vuex with Pinia, and moved from Vue CLI to Vite.
  • The design came from another agency and was implemented closely with the designer.
  • We later added GLUU authentication via OpenID.
  • All code was covered by Jest tests; components, services, helpers, views, and stores had high coverage, including simulated user interactions.
  • I researched migrating tests from Jest to Vitest, but the budget wasn’t approved.
  • I also built CSV exports from the PIM via Azure Data Factory, modeling pipelines and dataflows.
  • For large downloads, I created an Azure Logic App to gather up to 500,000 IDs and trigger client downloads, since client-side lookup was too slow.
  • I supported the team extending an internal price-management tool—a Vue project with an Azure Functions (C#) backend—by expanding both frontend and backend.
  • Technologies: C# .NET 6.0, EF Core, Vue.js 3, TypeScript, Vite, SCSS, Jest, Azure Data Factory, Azure API Management, Azure Functions, Microsoft Cognitive Search
Sep 2021 - Jan 2023
1 year 5 months

Lead Fullstack-Developer

Starbase Nexus

  • Open Source community project with Vue.js 3 frontend and C# backend.
  • This is an open source community project on .NET 5 C# and Vue.js 3 with TypeScript.
  • I wrote all the code so far; others can contribute later.
  • The goal is to collaborate internationally and try new ideas.
  • The backend is cloud-ready and horizontally scalable.
  • We chose a database-friendly approach since scaling databases is costly and this is a non-profit project.
  • Technologies: C# .NET 5.0, EF Core, Vue.js 3, TypeScript, Vue CLI, SCSS, Augmented-UI
Jul 2021 - Feb 2022
8 months

Senior Frontend-Developer

Tivian (formerly Questback)

  • Developing a dashboard management/admin panel.
  • This is an admin interface for the Dashbo project, where admins configure dashboard projects and set data sources.
  • The frontend is similar to the above project: Vue.js 3 with TypeScript, plus Tailwind UI and Tailwind CSS.
  • The backend is Node.js/Express with TypeScript, and the REST API is documented with Swagger.
  • Due to an NDA, I can’t share more on other connected technologies.
  • Both frontend and backend are cloud-ready and run on AWS. Jest tests cover both, with a high coverage focus including negative tests and error handling.
  • Technologies: Vue.js 3, TypeScript, Node.js, Docker, Express, SCSS, Tailwind CSS, Tailwind UI
Dec 2020 - Nov 2022
2 years

Senior Fullstack-Developer

As Good as Pros

  • Developing an app for booking sports events during COVID-19, with Vue.js 3 frontend and C# backend (part-time).
  • For this startup, I built an app and backend to offer and book sports events digitally and on-site.
  • We needed to collect personal data per COVID regulations.
  • Features:
  • Create events (online & on-site)
  • Assign trainers/hosts
  • On-demand billing for events or subscriptions
  • Broadcast event updates
  • Transactional emails and push notifications
  • Social logins (SSO)
  • Tech stack:
  • Backend: C# .NET 5 REST API with EF Core connecting to MySQL 8
  • Frontend: Vue.js 3 with TypeScript as a PWA
  • Cloud-ready on AWS EC2, can move to container service with autoscaling
  • Push notifications via SignalR/WebSockets (action and time triggers)
  • Automated transactional email service
  • Technologies: C# .NET 5.0, EF Core, Vue.js 3, TypeScript, Vue CLI, SCSS, PWA, PayPal Checkout, PayPal Subscriptions, Stripe, Service Worker, SignalR, WebSockets
Nov 2019 - Sep 2021
1 year 11 months

Senior Frontend-Developer

Tivian (formerly Questback)

  • Building a dashboard application (Dashbo) (employed 2019-11 to 2021-02).
  • Dashbo is a product by Tivian (formerly Questback) showing employee feedback stats on simple dashboards.
  • We aimed to replace Tableau, which was too complex and costly for many cases.
  • The frontend used Vue.js 2 class-based components, all custom except Vue Tours.
  • We focused on UX with subtle animations and accessible color choices, plus a theming option for corporate identities.
  • The backend is Node.js/Express REST API in TypeScript.
  • We used Apache Kafka for fast data access from feedback databases.
  • The whole project is cloud-native without vendor lock-in for maximum flexibility.
  • Technologies: Vue.js 3, TypeScript, Node.js, Docker, Express, SCSS
Sep 2019 - Apr 2021
1 year 8 months

Lead Fullstack-Developer

Hyperion Headquarters

  • C# student project for a community website with over 7,000 active members.
  • This was my first large C# project to gain practical experience.
  • It served the community around the MMO Dual Universe, which had up to 10,000 simultaneous users.
  • The project had over 7,000 registered users.
  • I built services and tools to enhance the game experience, including:
  • CDN with file upload, image & video optimization
  • Media gallery
  • Crafting calculator (recursive resource calculation)
  • Ship catalog (product catalog)
  • Data comparison tools
  • JWT role-based authentication/authorization
  • SSO with Discord, GitLab, NodeBB
  • The backend is C# ASP.NET Core 3.1 with REST API and Swagger, using MySQL 8.
  • The frontend is Vue.js 2 Options API.
  • Styling with SASS (SCSS) and BEM for maintainability.
  • For media processing I used ImageMagick and FFmpeg in C#.
  • Hosted on a Hetzner Ubuntu 18.04 root server.
  • Technologies: C# ASP.NET Core 3.1, EF Core, Vue.js 3, TypeScript, Vue CLI, SCSS, ImageMagick, FFmpeg, GitLab, NodeBB, Discord OAuth2
Mar 2014 - May 2019
5 years 3 months

Senior Fullstack-Developer

CHRONEXT

  • Developing a shop system and fulfillment tool for a luxury watch online store and leading the shop team (employed).
  • At CHRONEXT I was the lead e-commerce developer until May 2019.
  • The backend was custom with Slim Framework, starting on PHP 5.6 and later upgraded to 7.1, using MySQL 5.7.
  • We integrated Algolia for high-performance search at scale, backed by Elasticsearch and MongoDB with AI support.
  • Since Nuxt and Next weren’t established, we server-rendered the frontend and used jQuery for dynamic parts.
  • Challenges included strict SEO requirements (meta-data, structured data, sitemaps) and integrating payment providers (PayPal, Finetrade, SOFORT).
  • We also built monitoring and admin tools: backend in Symfony 4 and Laravel, frontend in Vue.js 2 Options API.
  • Product data management also used these techs and was mainly my work.
  • Technologies: PHP 5.6–7.1, jQuery, Vue.js 2, Slim Framework, Symfony 4, Laravel, PayPal, Google Analytics, Facebook API, CrazyEgg, FineTrade, SOFORT, anti-fraud tools, SCSS, BEM, MySQL 5, Algolia
Jul 2013 - Mar 2014
9 months

Fullstack-Developer

inVentiv Health

  • Developing pharma websites on TYPO3 about drugs and treatments (employed).
  • Early in my career, I worked at two agencies building small to medium TYPO3 projects.
  • These projects used PHP, SCSS (SASS), JavaScript, jQuery, and MySQL, mainly for corporate or product websites.
  • Technologies: PHP 5, jQuery, SCSS (SASS), TYPO3, JavaScript
Oct 2010 - Jun 2013
2 years 9 months

Junior Fullstack-Developer

FH-Konzept

  • Developing websites for clients like Schwank, JG Gruppe, Sikkens Joinery, etc., on TYPO3 (employed).
  • Early in my career, I worked at two agencies on small to medium TYPO3 projects for various clients.
  • We used PHP, SCSS (SASS), JavaScript, jQuery, and MySQL for corporate and product websites.
  • Technologies: PHP 5, jQuery, SCSS (SASS), TYPO3, JavaScript
Summary

I am a Fullstack Developer with over 14 years of professional experience. Through my career and freelancing, I gained insights into many industries, companies, teams, and especially people. I worked not only as a front- and backend developer but also took on several leadership roles.

Languages
German
Native
English
Advanced
Certifications & licenses

Udemy Certificates in AWS Cloud

Udemy

Udemy Certificates in Adobe Illustrator

Udemy

Udemy Certificates in C# AspNetCore 3.1 - .NET 8

Udemy

Udemy Certificates in Docker

Udemy

Udemy Certificates in TypeScript

Udemy

Udemy Certificates in Vue.js 2 - 3

Udemy

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