GitHub/benruehl
Visit my GitHub profile for more projects, contributions and experiments.
- C# 37.0%
- Astro 18.0%
- Kotlin 15.0%
- Java 13.0%
- JavaScript 8.0%
- TypeScript 5.0%
- CSS 2.0%
- Svelte 1.0%
Building Software, Front to Back
With 10+ years of experience building software across industries such as e-commerce, energy, and project management, I thrive in both frontend and backend development. My current focus lies in Kotlin, Spring Boot, TypeScript, and React, but I adapt flexibly to the needs of each project.
Along the way, I’ve mentored junior developers, contributed to architectural decisions, and emphasized testing and clean practices as the foundation for sustainable, collaborative development.
Highlights
Professional Experience
- Kotlin TypeScript—
Senior Fullstack Engineer at idealo
Owned the idealo homepage, serving 2M requests per day. Launched 30 A/B tests, vastly overhauling the homepage's user experience. Monitored and optimised application performance and resilience, e.g. by implementing caching strategies and handling bot traffic. Managed technical infrastructure on AWS via Infrastructure as Code using AWS CDK, ECS, and GitHub Actions.
- Kotlin—
Software Engineer at Bringmeister (acq. Rohlik Group)
Contributed to expansion efforts of going from regional to nationwide delivery. Built event-based microservices for aggregating product data from internal and external partners, providing the data base for the online shop and other departments.
- C# TypeScript—
Fullstack Developer at IT&I
Worked with customers directly, giving technical advice, estimates and feature presentations. Created and owned several content management modules and applications for customers' websites and intranet. Created an in-house release management tool now used by multiple engineering teams. Conducted several technical interviews, helped to on-board new hires as a Buddy and mentored working students.
- C# JavaScript—
Fullstack Developer at microTOOL
Created the RESTful API, an add-on system, role-based access control UI, glossary management, and other features for an Application Lifecycle Management product line. Mentored several working students, providing guidance on company-related projects.
Personal Projects
I am passionate about building beautiful and engaging user interfaces.
Personal projects are a way for me to channel my creativity and to explore new realms of design and technology.
2018 — 2021
Adonis UI
Lightweight yet comprehensive UI toolkit for WPF applications. It introduces features such as dark mode, flexible spacing and layering systems, customizable windows, and a modernized look and feel, while staying highly customizable.
As one of my biggest personal projects, it taught me valuable lessons in handling community feedback, publishing packages, creating accessible documentation, and exploring WPF’s technical internals.
1,853
120k
2024 — 2025
Benjamin's Bowls
My personal recipe collection. It combines the clarity of a cookbook with the playful visuals of a trading card game, creating a unique and memorable experience. All illustrations are hand-drawn by me.
2023 — 2024
Steffis Krümelkiste
Business website for a child daycare facility. Formerly built with Gatsby, now rebuilt with Astro in its third iteration. The site consistently receives positive feedback from visiting parents.
2014 — 2016
Musicate
Educational tool designed for music teachers and pupils. Introduced and used by classes in two elementary schools.
2025
Portfolio
The software engineering portfolio you’re exploring right now. Built with Astro's static site generation, htmx for interactivity, and plain SCSS for styling. Achieving perfect 100 / 100 scores in every Lighthouse metric.
What Shapes My Work
My approach to software engineering is built on precision, adaptability, and collaboration. I thrive on tackling diverse challenges, moving seamlessly between technologies while helping others succeed.
Striving for Excellence
I hold myself to high standards, paying close attention to details that make solutions both maintainable in code and seamless for users.
Growing with Challenges
Versatility lets me move confidently between stacks and problems, always discovering smarter ways to build and improve.
Building Together
I thrive in teams that share, support, and celebrate success together. My focus is on helping others excel while strengthening how we work.
When Benjamin joined our team, I was truly impressed by his exceptional commitment and how thoroughly he’s grasped both the technical and functional aspects of our work. His deep understanding and high personal standards have led him to continually challenge both the team’s status quo and himself.– Jan-Hendrik Peters, Team Lead at idealo
I find it particularly remarkable how Benjamin manages to evoke emotion through his work. With great attention to detail, coupled with his ability to bring web front-ends to life with well-balanced animations, he is able to create a wonderful user experience.– Philipp Thomas, Senior Fullstack Engineer at idealo
Beyond his technical skills, Benjamin has exceptional problem-solving abilities. He doesn't just settle for the obvious or initial proposed solutions. Instead, he takes the time to understand the problem and often comes up with more efficient and elegant solutions that are better suited for the specific challenge, always with performance and maintainability in mind.– Naseem Shawarba, Fullstack Developer at idealo
When we introduced new initiatives for the upcoming quarter, he immediately engaged, showing genuine excitement to drive these forward. His proactive approach and commitment has both advanced our work and inspired the team to aim higher together.– Frederic von Vlahovits, Product Owner at idealo
Broad Hands-on Experience — Tech I Used in Real Projects
JS
- TypeScript
- React
- Next.js
- Vue.js
- Svelte
- Astro
- CSS / SCSS
- Node.js
- Vite
- Jest / Vitest
JVM
- Kotlin
- Spring Boot
- Webflux / Reactor
- Vaadin
- Gradle
- JUnit
.NET
- C#
- .NET Core
- .NET Framework
- ASP.NET
- WPF
- EF Core
- NHibernate
- MSTest
Infrastructure
- MongoDB
- Amazon DynamoDB
- SQL Server
- Kafka
- Amazon Kinesis
- Amazon ECS
- Docker
- AWS CDK
- Terraform
Testing
- Playwright
- Cypress
- Wiremock
- Pactflow
Tooling
- GitHub Actions
- Azure DevOps
- Bitbucket Pipelines
- GrowthBook
- Storybook
- Snowplow
- Algolia
- Grafana
- Datadog
- Git
Today I Learned
Standout lessons I've picked up recently, both from hands-on experience and fresh ideas I've encountered.