A personal activity and health tracking app. Integrates with Strava to import fitness activities, matches and visualizes metrics over time (like performances on segments). Includes coach AI-agent for full structured workout planning. The backend is written in Go with PostgreSQL, the frontend in React with TypeScript.

A spelling practice app for German elementary school students. Words are read aloud via Google Cloud Text-to-Speech and the student types the spelling. Includes gamification with achievements, levels and streaks, multiple game modes, daily challenges and offline support as a Progressive Web App. The backend is written in Go, the frontend in vanilla JavaScript.

A macOS backup tool that uses restic for incremental folder backups to S3, scheduled automatically via launchd. Also supports ad-hoc single-file backups with GPG encryption. Includes an interactive setup wizard for configuring AWS credentials, backup folders and notifications.

App that reduces the number of news sources that I need to scan by sending RSS and Atom feeds to my email inbox. I wrote down some more details and lessons in this post. Written in Go, ships as a single binary.

CLI tool that allows adhoc creation of JSON objects via command line arguments and by reading files. The goal was to quicky create JSON objects that can be piped into other tools when massaging streams of JSON data. Written in Go, ships as a single binary.

Originally my goal was faster startup time than the tools that shipped with Apache Kafka and to allow more fine-grained specification of offsets when consuming streams. The project grew to also allow for producing messages and basic topic administration. Written in Go and heavily relies on shopify/sarama, ships as a single binary.

A small webapp to serve and share photo albums that are organized in a simple folder structure. It continuously polls a given folder recursively for changes and generates thumbnails and HTML files as it finds new images. Here is a demo with cats 😉. Written in Go, ships as a single binary.

Emacs package that leverages the built-in thing-at-point functionality to identify what to highlight and hi-lock to highlight it efficiently. I wanted a minor mode that works well on larger files and it turns out you just have to combine built-ins to achieve it. Can be installed via MELPA.