Distributable {box} modules with 'carrier'

[joshuamarie]

For the past month I've been building carrier, a Rust-based package manager that makes {box} modules manageable and distributable across systems. Similar to pip or cargo, but for {box}.

It's early beta stage but functional, so I wanted to share it here before pushing toward a proper alpha.

What it does

carrier lets you bundle a {box} module into an archive, publish it (or share it via GitHub), and install it on another machine — with CRAN dependencies resolved automatically. Once installed, the module is importable through box::use() without any path fiddling.

Command-line Interface

Rust projects have their own command line interface (CLI), such as Posit's 'air', so I made one.

carrier init <name>         # scaffold a new module project
carrier bundle <path>       # compress the module into a .tar.gz archive
carrier install <source>    # install from a directory, archive, or gh:user/repo
carrier remove <name>       # uninstall a carrier package

How it hooks into {box}

I patched three files in the {box} source to teach it about carrier packages as a third module kind, alongside local modules and R packages:

• spec.r: 'carrier' packages are importable without . or .. prefixes, and submodule/name imports work exactly as they do for local modules.
• info.r: 'carrier' packages get their own class, and find_mod() is extended to locate them in the carrier library.
• paths.r: added crr_mod_search_path(), which resolves where 'carrier' packages are installed. spec.r depends on this.

Demo

Using the convert module (a unit conversion toolkit I bundled as a test case):

box::use(
    convert,
    convert/mass,
    tmp = convert/temp
)

convert$mass$basic_mass$g_to_kg(1000)
#> [1] 1

mass$basic_mass$g_to_kg(1000)
#> [1] 1

convert$temp$celsius_to_fahrenheit(100)
#> [1] 212

tmp$celsius_to_fahrenheit(100)
#> [1] 212

box::unload(convert)
box::unload(mass)
box::unload(tmp)

What's still missing

Note: 'carrier' is still on the early beta stage. It lacks the following:

• Unit tests
• Documentation

Why "carrier"?

I originally built this to distribute my own deep learning modules between machines. The name stuck.

Follow-up Question

Is it time now for {box} modules to become distributable?