Buck: ocaml_library()
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This is liable to change in the future.

A ocaml_library() rule builds a native and a bytecode libraries from the supplied set of OCaml source files and dependencies.

Note: Buck is currently tested with 4.X OCaml series.


  • name (required) #

    The short name for this build target.

  • srcs (required) #

    The set of source files to be compiled by this rule. It supports *.ml, *.mli, *.mly, *.mll, and *.c files. (see this test as C interop example and this test as parser and lexer example).

  • deps (defaults to []) #

    The set of dependencies of this rule. It could include references to ocaml_library and cxx_library rules.

  • platform_deps (defaults to []) #

    Platform specific dependencies. These should be specified as a list of pairs where the first element is an un-anchored regex (in java.util.regex.Pattern syntax) against which the platform name is matched, and the second element is a list of dependencies (same format as deps) that are exported if the platform matches the regex. See deps for more information.

  • compiler_flags (defaults to []) #

    The set of additional compiler flags to pass to ocaml compiler. It supports specifying ppx (see for example).

  • tests (defaults to []) #

    List of build targets that identify tests that exercise this target.

  • visibility (defaults to []) #

    List of build target patterns that identify the build rules that can include this rule as a dependency, for example, by listing it in their deps or exported_deps attributes. For more information, see visibility.

  • licenses (defaults to []) #

    Set of license files for this library. To get the list of license files for a given build rule and all of its dependencies, you can use buck query.

  • labels (defaults to []) #

    Set of arbitrary strings which allow you to annotate a build rule with tags that can be searched for over an entire dependency tree using buck query attrfilter().


For more examples, check out our integration tests.