Michel Mauny, 1959-2026

Community
1

Dear all,

It is with great sadness that we (the OCaml Software Foundation) are sharing the news of the death of Michel Mauny, a long-time member of the OCaml community. Michel passed away on September 17th 2026 (more information, in French).

During his career as INRIA research scientist, professor at ENSTA and CEO of Nomadic Labs, and among his many contributions, Michel:

  • co-authored in 1985 the paper that started Caml: “The Categorical Abstract Machine”, Cousineau, Curien, Mauny (PDF) ;
  • actively contributed in the late 80s to the “Heavy Caml” implementation that predated Caml Light and OCaml ( see https://ocaml.org/history for more details ) ;
  • introduced stream parsers with Daniel de Rauglaudre (1992 tech report), designed and co-maintained the camlp4 preprocessor ;
  • wrote with Guy Cousineau the first book in English about OCaml, “The functional approach to programming” (1998) ;
  • taught (O)Caml in French universities and engineering schools throughout his career (Paris 7, Polytechnique, ENSTA) ;
  • advised several PhD students, including several who remained active in the OCaml community: Grégoire Henry, Çağdaş Bozman, Benoît Vaugon and Pierrick Couderc ;
  • created in 2001 the Caml Consortium, an earlier structure for industrial users to participate in and fund the development of OCaml at INRIA ;
  • created in 2018 the OCaml Foundation, with the more ambitious goals of collecting more funds to also support the broader OCaml software ecosystem. Michel had to leave the OCaml Foundation when he moved from INRIA to Nomadic Labs, and we try our best to follow his vision.

This solemn moment is also an occasion to reflect on the rich history of our OCaml ecosystem, which grows by a collection of individual contributions. As we mark Michel’s passing, we celebrate and thank him, as well as the many individuals who dedicate their time and effort, often over decades, to building our programming commons.

63 Likes
2

For me, The Functional Approach to Programming was completely transformative. It and ML for the Working Programmer were the two texts that helped me to actually understand FP and ML.

I remember vividly reading Cousineau and Mauny, at our picnic table outside my house, beer in hand, and typing away at my ThinkPad. (It was always a ThinkPad, so that’s no memory but the book and picnic table and beer are.)

I guess I haven’t read it in years now–probably to my detriment. But I knew it was on our expansive bookshelves and found it immediately. It’s such a lovely book, worth at least a few minutes before going to sleep tonight.

IMG_0632
IMG_06323024×4032 1.5 MB

13 Likes
3

Every couple of years I pull it out because §5.1.1 has all the terminology and dimensions for tree traversal in one or two pagraphs.

4 Likes
4

This is terribly sad news, thank you for letting us know Gabriel. I found this on the French website (translated to English), which might be helpful for others who wish to express their sympathy:

In memory of Michel, the family wishes that people wishing to show their sympathy can, rather than by sending flowers, make a donation to the Cognacq-Jay Foundation, in support of its actions in favor of the most vulnerable https://donner.cognacq-jay.fr/

5 Likes
5

Me too, but for the excellent description of type synthesis with destructive unification in Chapter 13.

3 Likes