Build multiple OCaml executables in one Dune Project

Create a dune project

Follow these steps to create a new dune project if you don't already have one.

• First, initiate the project structure.

    dune init project foo
  

• It will create a project structure like this

• 

  The bin folder contains the source file for the main executable main.ml

• the bin/dune file has the build instruction for the executable, it'll look something like this.

    (executable
     (public_name foo)
     (name main)
     (libraries foo))
  

Adding Support to build multiple executables

• Let's see how to add support to build another executable called bar, which we'll write in the file called bar.ml.

• First, create a file called bar.ml in the bin directory.

• Then you can update the bin/dune file support multiple executables like below.

    (executables
     (public_names foo bar)
     (name main bar)
     (libraries foo))
  

Build and run the different executable

You can use the following commands to run the different executables.

dune exec ./bin/main.exe
dune exec ./bin/bar.exe

To build you can run following

dune build ./bin/main.exe
dune build ./bin/bar.exe

To run the built executables

 ./_build/default/bin/main.exe
 ./_build/default/bin/bar.exe