Today I’m releasing Abendrot—the free, open-source Mac app for your circadian rhythm.
I’ve become deeply interested in health and wellness with a holistic, functional approach to maximizing health and live. The deeper I went into the research, the harder it became to ignore the role light plays in the body’s daily timing, especially the blue and cyan short-wavelength light emitted by screens at night.
I got tired of countless nights staring into a luminous computer screen blasting blue-rich light at my eyes long after sunset. Grounded in peer-reviewed light research, Abendrot is my first-principles response: reduce the specific melanopic light that tells your body clock it is still daytime.
What the research changed for me
Light is not only visual. The eye also contains melanopsin-sensitive cells that help synchronize the body clock and respond strongly to short-wavelength blue-cyan light2. Thew problem at hand: an evening screen is not just bright or uncomfortable; its spectrum is a signal.
A 2023 controlled display study1 made the design direction more concrete. In 72 healthy men ages 18–35, researchers changed melanopic irradiance while holding ordinary luminance and color appearance constant. Lower-melanopic evening light was associated with less melatonin suppression and earlier melatonin onset; at the brightest tested condition, participants also fell asleep faster. Expert consensus2 points in the same direction: reduce melanopic light in the hours before sleep, and remember that intensity still matters. The research also shows that people vary widely in their sensitivity to evening light3, which is why Abendrot is adjustable and why I think of it as a practical input-side tool—not a promise of a sleep outcome.
I wanted the product to feel as thoughtful as its premise. Abendrot is a native Mac app that warms built-in and external displays around sunset, lets you reveal true color when accuracy matters, and keeps its settings and stats local. The goal was not another utility you tolerate. It was beautiful software that can quietly become part of your evening.
A few months ago, I could not have moved from research and concept to product design, engineering, brand, website, distribution, and launch at this speed. With agent orchestration and AI tools such as Claude Code and Codex, I took Abendrot from idea to market in days.
That speed is the real magic of this release. AI did not replace taste, responsibility, research, or product judgment; it compressed the distance between them. I could stay close to every decision while coordinating specialized agents across the entire journey from zero to one.
Abendrot is available now. It is free forever and open source.
I plan to keep turning ideas into useful, beautiful software at this pace, with more apps and tools coming soon.