Project Structure

Every Fe project follows a standard structure with a manifest file and source directory.

Directory Layout

A minimal Fe project looks like this:

my-project/
├── fe.toml
└── src/
    └── lib.fe

As your project grows:

my-project/
├── fe.toml
└── src/
    ├── lib.fe           # Entrypoint
    ├── token.fe         # Additional modules
    ├── utils.fe
    └── messages/
        ├── mod.fe       # Submodule entrypoint
        └── transfer.fe

The fe.toml Manifest

The fe.toml file defines your ingot’s metadata and dependencies:

[ingot]
name = "my_project"
version = "1.0.0"

[dependencies]
# Dependencies go here

The [ingot] Section

Every fe.toml requires an [ingot] section with:

Field	Required	Description
name	Yes	The ingot name (used for imports)
version	Yes	Semantic version string

[ingot]
name = "token_library"
version = "0.1.0"

The name must be a valid identifier. Use underscores instead of hyphens:

# Good
name = "my_token"

# Bad - hyphens not allowed
name = "my-token"

The src/ Directory

All Fe source files live in the src/ directory. The compiler discovers files matching the pattern src/**/*.fe.

The Entrypoint: src/lib.fe

Every ingot must have a src/lib.fe file. This is the entrypoint that defines what the ingot exports:

src/lib.fe

// Re-export items from other modules
pub use token::Token
pub use messages::Transfer

// Define items directly
pub struct Config {
    pub max_supply: u256
}

Organizing with Modules

Split code across multiple files for better organization:

src/lib.fe

pub use token::Token
pub use utils::calculate_fee

// src/token.fe
pub contract Token {
    // ...
}

// src/utils.fe
pub fn calculate_fee(amount: u256) -> u256 {
    amount / 100
}

Submodules

Create subdirectories with mod.fe files for deeper organization:

src/
├── lib.fe
└── messages/
    ├── mod.fe        # Required for submodule
    ├── transfer.fe
    └── approval.fe

src/messages/mod.fe

pub use transfer::Transfer
pub use approval::Approval

Creating a New Project

To create a new Fe project:

1. Create the project directory:

   mkdir my_project
   cd my_project

2. Create fe.toml:

   [ingot]
   name = "my_project"
   version = "0.1.0"

3. Create the source directory and entrypoint:

   mkdir src
   touch src/lib.fe

4. Add your code to src/lib.fe:

   pub contract MyContract {
       // ...
   }

Summary

Component	Purpose
fe.toml	Manifest with name, version, dependencies
[ingot]	Required section with name and version
src/	Contains all source files
src/lib.fe	Required entrypoint
src/**/*.fe	Additional source files