Install Version

asdf install <name> <version>
# asdf install erlang 17.3

If a plugin supports downloading & compiling from source, you can specify ref:foo where foo is a specific branch, tag, or commit. You'll need to use the same name and reference when uninstalling too.

List Installed Versions

asdf list <name>
# asdf list erlang

List All Available Versions

asdf list-all <name>
# asdf list-all erlang

Set Current Version

asdf global <name> <version> [<version>...]
asdf local <name> <version> [<version>...]
# asdf global elixir 1.2.4

global writes the version to $HOME/.tool-versions.

local writes the version to $PWD/.tool-versions, creating it if needed.

See the .tool-versions file in the Configuration section for details.

?> Alternatively, if you want to set a version only for the current shell session or for executing just a command under a particular tool version, you can set an environment variable like ASDF_${TOOL}_VERSION.

The following example runs tests on an Elixir project with version 1.4.0. The version format is the same supported by the .tool-versions file.

ASDF_ELIXIR_VERSION=1.4.0 mix test

View Current Version

asdf current
# asdf current
# erlang 17.3 (set by /Users/kim/.tool-versions)
# nodejs 6.11.5 (set by /Users/kim/cool-node-project/.tool-versions)

asdf current <name>
# asdf current erlang
# 17.3 (set by /Users/kim/.tool-versions)

Uninstall Version

asdf uninstall <name> <version>
# asdf uninstall erlang 17.3

Shims

When asdf-vm installs a package it creates shims for every executable program in that package in a $ASDF_DATA_DIR/shims directory (default ~/.asdf/shims). This directory being on the $PATH (by means of asdf.sh or asdf.fish) is how the installed programs are made available in the environment.

The shims themselves are really simple wrappers that exec a helper program asdf-exec passing it the name of the plugin and path to the executable in the installed package that the shim is wrapping.

The asdf-exec helper determines the version of tha package to use (as specified in .tool-versions file, selected by asdf local ... or asdf global ...), the final path to the executable in the package installation directory (this can be manipulated by the exec-path callback in the plugin) and the environment to execute in (also provided by the plugin - exec-env script), and finally it executes it.

!> Note that because this system uses exec calls, any scripts in the package that are meant to be sourced by the shell instead of executed need to be accessed directly instead of via the shim wrapper. The two asdf-vm commands: which and where can help with this by returning the path to the installed package:

# returns path to main executable in current version
source $(asdf which ${PLUGIN})/../script.sh

# returns path to the package installation directory
source $(asdf where ${PLUGIN} $(asdf current ${PLUGIN}))/bin/script.sh