The software I publish is written with the standard techniques of the profession : redux, KISS, DRY, modularisation, encapsulation, balanced between OOP and functional etc. It is also based on the modern tools of the industry in the cloud : continuous and automatic unit testing, integration, deployment, monitoring. A great care is taken to publish and maintain high-quality open-source components, to not only serve the astronomical community but the software developers one too.

APIs & services for astronomical data:

iObserve on macOS and iOS

open-source astro libraries

open-source components for macOS pro apps


My name is Cédric Foellmi, a.k.a @onekiloparsec. I am a former professional astronomer, with research subjects going from Wolf-Rayet stars, micro-quasars to quantum optics. Like many modern astronomers, I acquired a large experience at manipulating big telescopes and large datasets. I have been working 4 years for E.S.O. in Chile, spending a "year of nights" (about 360+) in the beautiful La Silla Observatory, hence the pictures of this site. I currently work as Head of Software in a tech startup focusing on Virtual Reality. 

Here you will find everything about the software I write. I am mostly located on the Internet during waking times. But on Earth I am located in the Alps, between France and Switzerland. 

The origin of this url, which became my signature, is to be found in the work I've done about a given black-hole in our galaxy.

Image Credits: P. Horálek/ESO (top) – myself (bottom)