The ESRF community has lost a pioneer, an outstanding scientist and engineer, and a colleague whose creativity, generosity, and technical vision have left a lasting mark on our facility.

Fabio joined the ESRF during its earliest years, when the laboratory was still under construction and every instrument, laboratory, and experimental capability had to be imagined before it could be built. He became one of the architects of the foundation that would establish the ESRF as an international reference in synchrotron science.

His career was defined by a rare blend of imagination, technical mastery, and determination. Together with colleagues including Salvador Ferrer, he established the ESRF Surface X-ray Science group and helped develop new experimental methods that opened entirely new possibilities for the study of surfaces and interfaces.

Fabio had a rare gift: he turned problems that seemed impossible into elegant, practical solutions. The hardest instrumentation challenges appeared to energise rather than discourage him. Throughout his career, he repeatedly demonstrated an extraordinary ability to design original systems, combining precision engineering, and deep physical understanding.

One contribution stands out. In 1992, he conceived and built the first ESRF X-ray monochromator based on a concept that would go on to inspire instruments here and at synchrotrons around the world. More than three decades later, that original design is still in operation and still evolving, a remarkable testament to the quality and foresight of his work.

Fabio also pioneered the use of hexapod positioning systems at the ESRF, showing that these versatile platforms could deliver sub-micrometre precision while handling objects ranging from a few grammes to several tonnes. Today the concept is standard practice in synchrotron beamlines and large-scale facilities worldwide, one more example of how Fabio's innovations quietly became part of the everyday toolbox of modern experimental science.

As Head of the Scientific Infrastructure group, he continued to take on the most demanding technical challenges, often those that others considered too difficult, and found workable solutions where none seemed to exist. His work reached far beyond any single beamline, helping to shape the technological capabilities that have supported thousands of experiments over the years.

Fabio made many scientific contributions and coordinated numerous European instrumentation projects. Yet those who worked with him will remember something even more enduring than these achievements: his curiosity, his enthusiasm, his willingness to share ideas, and the sheer joy he found in talking about science long after the working day was over.

Top image: Fabio Comin in 2013.