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ocaml-webmachine is a layer on top of cohttp that implements a state-machine-based HTTP request processor. It's particularly well-suited for writing RESTful APIs. As the name suggests, this is an OCaml port of the webmachine project.

Build Status


Install the library and its depenencies via OPAM:

opam install webmachine

Getting Started

webmachine implements this decision diagram to determine how an HTTP request should be handled. This includes validation, authentication, content negotiation, and caching. A resource specifies the decision that should be made at each node in the diagram by defining the appropriate method in a resource subclass. The correspondence is suggested by the name of the method for now. This will be better-documented in the future.


To build the examples in the examples/ subdirectory:

dune build examples/hello_lwt.exe
dune build examples/crud_lwt.exe
dune build examples/hello_async.exe


To install development dependencies, pin the package from the root of the repository:

opam pin add -n webmachine .
opam install --deps-only webmachine

After this, you may install a development version of the library using the install command as usual.

For building and running the tests during development, you will need to install the oUnit package and run tests:

opam install oUnit
dune runtest


BSD3, see LICENSE file for its text.