hx add

Add dependencies to your project.

Synopsis

hx add <PACKAGES>... [OPTIONS]

Description

The add command adds one or more package dependencies to your project. It updates your .cabal file and optionally updates the lockfile.

Arguments

PACKAGES...             Package names (with optional version constraints)

Options

    --dev               Add as development dependency (test/bench only)
    --lib               Add to library dependencies
    --exe <NAME>        Add to specific executable
    --test <NAME>       Add to specific test suite
    --bench <NAME>      Add to specific benchmark
    --no-lock           Don't update lockfile
-v, --verbose           Show detailed output

Examples

Add Single Package

hx add text

Add Multiple Packages

hx add text containers aeson bytestring

Add with Version Constraint

# Exact version
hx add "aeson ==2.1.0.0"

# Version range
hx add "aeson >=2.0 && <2.2"

# Major version bound
hx add "aeson ^>=2.1"

Add as Dev Dependency

# Added to test-suite dependencies only
hx add --dev hspec QuickCheck

# Added to benchmark dependencies only
hx add --bench criterion

Add to Specific Component

# Add to library
hx add --lib text

# Add to specific executable
hx add --exe my-cli optparse-applicative

# Add to specific test suite
hx add --test unit-tests hspec

Version Constraints

hx supports Cabal version constraint syntax:

What It Does

1. Parses package specifications
2. Validates package exists on Hackage
3. Updates .cabal file with new dependencies
4. Updates lockfile (unless --no-lock)

Before

library
  build-depends:
    , base ^>=4.18

After hx add text containers

library
  build-depends:
    , base ^>=4.18
    , containers
    , text

Development Dependencies

Development dependencies are only needed for testing or benchmarking:

# Test dependencies
hx add --dev hspec QuickCheck hedgehog tasty

# Benchmark dependencies
hx add --dev criterion gauge tasty-bench

These are added to the appropriate component:

test-suite my-tests
  build-depends:
    , base
    , my-lib
    , hspec        -- Added by --dev
    , QuickCheck   -- Added by --dev

Package Discovery

If you’re not sure of the exact package name:

# Search on Hackage
hx search json

# Or browse https://hackage.haskell.org

Common Packages

Lockfile Behavior

By default, hx add updates the lockfile:

# Add and update lockfile
hx add text

# Add without updating lockfile
hx add text --no-lock

To update the lockfile later:

hx lock

See Also

• hx remove — Remove dependencies
• hx update — Update dependencies
• hx lock — Update lockfile