# Huff CLI

While most of the time you will be compiling your Huff contracts in a foundry project using the foundry-huff (opens new window) library, the compiler (opens new window)'s CLI offers some additional configuration options as well as some useful utilities.

# Options

huffc 0.3.0
Huff Language Compiler built in Pure Rust.


    <PATH>    The contract(s) to compile

    -a, --artifacts                       Whether to generate artifacts or not
    -b, --bytecode                        Generate and log bytecode
    -c, --constants <CONSTANTS>...        Override / set constants for the compilation environment
    -d, --output-directory <OUTPUTDIR>    The output directory [default: ./artifacts]
    -g, --interface [<INTERFACE>...]      Generate solidity interface for a Huff artifact
    -h, --help                            Print help information
    -i, --inputs <INPUTS>...              The input constructor arguments
    -n, --interactive                     Interactively input the constructor args
    -o, --output <OUTPUT>                 The output file path
    -r, --bin-runtime                     Generate and log runtime bytecode
    -s, --source-path <SOURCE>            The contracts source path [default: ./contracts]
    -v, --verbose                         Verbose output
    -V, --version                         Print version information
    -z, --optimize                        Optimize compilation [WIP]

    help    Print this message or the help of the given subcommand(s)
    test    Test subcommand

# -a Artifacts

Passing the -a flag will generate Artifact JSON file(s) in the ./artifacts directory or wherever the -d flag designates. The Artifact JSON contains the following information:

  • File
    • Path
    • Source
    • Dependencies
  • Bytecode
  • Runtime Bytecode
  • Contract ABI


huffc ./src/ERC20.huff -a

# -b Bytecode

Passing the -b flag will tell the compiler to log the bytecode generated during the compilation process to the console.


huffc ./src/ERC20.huff -b

# -c Constants

Arguments: [CONSTANTS]

Passing the -c flag allows you to override and set constants for the current compilation environment. Literals must be supplied in 0x format and be <= 32 bytes.


huffc ./Test.huff -c MY_CONST=0x01 MY_OTHER_CONST=0xa57b

# -d Output directory

Arguments: <OUTPUT_DIR>, Default: ./artifacts

Passing the -d flag allows you to designate the directory that the Artifact JSON file will be exported to.


huffc ./src/ERC20.huff -d ./my_artifacts

# -g Interface

Passing the -g flag will generate a Solidity interface for the Huff contract provided. This interface is generated based off of the function and event definitions within the contract.

The solidity file will always be named I<HUFF_FILE_NAME>.sol, and it will be saved in the same directory as the Huff contract itself.


huffc ./src/ERC20.huff -g

# -i Inputs


Passing the -i flag allows you to set the constructor arguments for the contract that is being compiled. All inputs should be separated by a comma. If you'd like to input the constructor arguments interactively instead, use the -n flag.

Example (assuming ERC20.huff's constructor accepts a String and a uint):

huffc ./src/ERC20.huff -i "TestToken", 18

# -n Interactive Inputs

Passing the -n flag allows you to input constructor arguments interactively through the CLI rather than via the -i flag.


huffc ./src/ERC20.huff -n

# -o Output

Arguments: <FILE_PATH>

Passing the -o flag allows you to export the artifact to a specific file rather than a folder.


huffc ./src/ERC20.huff -o ./artifact.json

# -s Source Path

Arguments: <CONTRACTS_FOLDER>, Default: ./contracts

Passing the -s flag allows you to change the directory that the compiler scans for Huff contracts.


huffc -s ./src/

# -r Runtime Bytecode

Passing the -r flag will tell the compiler to print the runtime bytecode of the compiled contract.

# -v Verbose Output

Passing the -v flag will tell the compiler to print verbose output during the compilation process. This output can be useful for debugging contract as well as compiler errors.


huffc ./src/ERC20.huff -v

# -z Optimize

Not yet implemented in the compiler (opens new window).

# Subcommands

# test

  • Format: huffc ./path/to/Contract.huff test [-f <list|table|json>] [-m <TEST_NAME>]

The test subcommand is the entry point to running tests within a Huff contract.

# Optional Flags

  • -f or --format: Formats the test report as a list, table, or JSON.
  • -m or --match: Runs a specific test with the name passed to this flag.