How to organize large projects in Zig language

Question

I used to break down my large c/c++ projects with CMake and then add each part to main project using add_submodule command (the smaller parts were static or dynamic libraries). Also I used the same solution to use third-party libraries in my project.

But I have trouble with doing the same in my zig projects. I had a hard time to search and try to find a reliable and reusable project structure just like CMake projects.

Is there any solution that make me be able to create smaller libraries (with a build.zig inside each) and use those parts in my projects? for example something like this structure:

|-- projectA
|-----| src
|-----|----| main.zig
|-----| libs
|-----|----| projectB
|-----|----------| src
|-----|---------------| hello.zig
|-----|----------| build.zig
|-----|----| projectC
|-----|----------| src
|-----|---------------| bye.zig
|-----|----------| build.zig
|-----| build.zig

I tried to use build.zig file to build each dependency but was not successful, also it's not a straightforward solution, I searched to find a solution but I found nothing.

I found something like exe.addModule but there is not such a function called addModule() in added executable structure.

Answer 1

You can add a dependency as a local package.

Let's say you have this folder structure:

|-- foo
|-----| src
|-----|----| root.zig
|-----| build.zig
|-- project
|-----| src
|-----|----| main.zig
|-----| build.zig
|-----| build.zig.zon

In foo, in build.zig:

_ = b.addModule("foo", .{
    .root_source_file = b.path("src/root.zig"),
    .target = target,
    .optimize = optimize,
});

In the project, in build.zig.zon:

.dependencies = .{
    .foo = .{
        .path = "../foo/",
    },
},

And, in build.zig:

const foo = b.dependency("foo", .{
    .target = target,
    .optimize = optimize,
});
exe.root_module.addImport("foo", foo.module("foo"));

So, in main.zig you can just do:

const foo = @import("foo");

I believe this code works in 0.12 and 0.13.