Björn Ruberg

The project is an MVP for a data analysis dashboard built on a powerful architecture that provides a foundation for future growth. It utilizes the modern React framework, Remix, and operates without traditional servers. Instead, it is deployed serverlessly using AWS stack-based Lambda functions. This approach offers clients the advantage of minimal ramp-up costs while ensuring excellent scalability. Connecting a CloudFront CDN allows the dashboard to be delivered globally for optimized performance.

Data visualization was powered by a Cube.js instance, serving as a speedy replacement for a custom back end. The front-end styling utilized Tailwind with Tremor and Flowbite UI libraries. OAuth 2 authorization was implemented using AWS Cognito. I received a perfect customer rating of 10 out of 10 stars for my work.

During the COVID-19 pandemic, the authorities in Germany mandated the maintenance of attendance lists for all types of gatherings. However, managing these lists posed significant challenges for hosts and proved to be an inconvenience for attendees. The manual process of filling out paper lists was time-consuming, raised data protection concerns, and often hindered effective contact tracing due to illegible handwriting. Although digital solutions emerged, they often required the installation of apps and raised questions about data protection.

To address these shortcomings, I developed an open-source software called Pricora. The software was designed to be installed on self-hosted servers with minimal hardware requirements. Pricora implemented strong asymmetric encryption, utilizing the host's password to encrypt personal data before writing it to disk. This ensured the data remained encrypted and unreadable without the host's password.

Attendees were asked to scan a QR code, which opened a web page in their browser. They could then enter their personal data using the browser's form auto-completion feature. The data was encrypted using a pubkey. In case authorities required it, hosts had the ability to export guest lists.

As part of Planeus's production planning system, I assumed responsibility for implementing substantial components. A significant focus of my work involved reviving the interactive Gantt timeline chart, which played a pivotal role in providing a comprehensive overview of the production process. At that time, the original implementation of vis.js had been left unmaintained. To address this challenge, I took the initiative to fork vis.js and its timeline module, enabling me to effectively customize it and meet the project's specific requirements. Importantly, it is worth noting that the development of vis.js was later resumed after my involvement.

KEY ACHIEVEMENTS
• Seamlessly integrated the Gantt timeline into the React application by developing a robust bridge between React and vis.js.
• Optimized performance by streamlining the vis.js codebase, eliminating unnecessary features, and enhancing its speed.
• Implemented a sophisticated collision detection algorithm in the front-end, facilitating efficient task scheduling.
• Devised client-side algorithms that enabled smooth item movement and resizing.
• Introduced comprehensive styling mechanisms, significantly enhancing the system's visual appeal and usability.

As a senior developer for a video deployment service, I built a lightweight cross-browser video player to deliver our videos to browser users. Available video player solutions like "video.js" and "media elements" had limitations, including bloated code and browser bugs.

To address these issues, I chose Preact (a 3KB alternative for React) as the foundation for the player, ensuring a lightweight design while benefiting from front-end rendering. The resulting video player was only 23KB in size, enabling fast fetching by browsers within two TCP roundtrips.

The improved video player significantly enhanced the user experience. It reduced video startup time by approximately one second, providing a seamless viewing experience for over 99% of users. Furthermore, the player resolved issues with pausing, resuming, and full-screen toggling, resulting in a bug-free experience.

Overall, my work on the video player contributed to a better user experience, faster video startup, and resolved compatibility issues, making video playback more enjoyable for most users.

The Planeus Workbench serves as the front-end of the Planeus production planning software, specifically designed for use by production workers on their mobile devices. Its purpose is to provide an intuitive interface for workers to interact with the Planeus system, allowing them to report progress and receive task instructions seamlessly.

To cater to mobile devices and establish an interface with the Planeus production plan, the Workbench was developed as a separate front-end system. In terms of technology, I opted for a similar stack as used in the main Planeus application, including React, MaterialUI, and Redux.

Leveraging my senior engineering experience, the Workbench benefitted from a cleaner and more streamlined codebase. This not only facilitated faster development but also enabled the successful implementation of modern UX patterns, resulting in excellent user acceptance.

By building upon a solid foundation and incorporating modern technologies, the Planeus Workbench provided an efficient and user-friendly solution for production workers. Its development and implementation were characterized by faster iterations, improved user experience, and widespread user adoption.