Where is the .mli files for Core installed by opam. It is under ~/.opam/4.00.1/lib/core where 4.00.1 is the version of OCaml used. For example, date.mli is under ~/.opam/4.00.1/lib/core/date.mli. Read more: Deploying ASP.NET Core 2.0 MVC application to Azure Web apps using Visual Studio 2017 NET Core 2.1 Release: Feature To Expect in 2018 Where are the backup files of my iPhone by iTune and how to get the real files from them? How to make ctags recognize specific files with certain extensions as C source files? How to make taglist recognize specific files with certain extensions as C source files? How to get files without certain strings in their files names (reverse of *string*) on Linux? Converting Movie Files to wav and mp3 Files Using MPlayer and LAME How to view .mbox files on Linux?