This is a plugin for rbenv that lets you set global and project-specific environment variables before spawning Ruby processes.

With Homebrew:

brew install rbenv-vars

Alternatively, with git:

git clone https://github.com/rbenv/rbenv-vars.git "$(rbenv root)"/plugins/rbenv-vars

Define environment variables in an .rbenv-vars file in your project, one variable per line, in the format VAR=value. For example:

RUBY_GC_MALLOC_LIMIT=50000000
RUBY_HEAP_MIN_SLOTS=15000
RUBY_FREE_MIN=4096

You can perform variable substitution with the traditional $ syntax. For example, to append to GEM_PATH:

GEM_PATH=$GEM_PATH:/u/shared/gems

You may also have conditional variable assignments, such that a variable will only be set if it is not already defined or is blank:

JAVA_OPTS?=-server -Xmx768m -Xms768m -Xmn128m -Xss20m

In the above case, JAVA_OPTS will only be set if $JAVA_OPTS is currently empty (i.e., if [ -z "$JAVA_OPTS" ] is true).

Spaces are allowed in values; quoting is not necessary. Expansion and command substitution are not allowed. Lines beginning with # or any lines not in the format VAR=value will be ignored.

Variables specified in the $(rbenv root)/vars file will be set first. Then variables specified in .rbenv-vars files in any parent directories of the current directory will be set. Variables from the .rbenv-vars file in the current directory are set last.

Use the rbenv vars command to print all environment variables in the order they'll be set.

1.2.0 (January 9, 2013)

• Fixed a bug where source files without a trailing newline could concatenate improperly with other source files on systems with GNU sed.
• Changed the output of rbenv vars to include the source file path in a comment above its variables, and an empty line between each source file, for easier debugging.
• Added support for rbenv help vars with rbenv 0.4.0.

1.1.0 (June 25, 2012)

• Added support for conditional variable assignments using ?=. Thanks to Scott Gonyea for the patch.

1.0.0 (September 27, 2011)

• Initial public release.

© 2012 Sam Stephenson. Released under the MIT license. See LICENSE for details.