nv is a lightweight utility to load context specific environment variables from either a single or multiple .env files before executing a command or command line program, along with its parameters.

As of version 2, the environment is cleared-out before loading context specific variables, except for $PATH.

~> brew update
~> brew tap jcouture/nv
~> brew install nv

~> mkdir nv
~> cd nv
~> set -x GOPATH $PWD
~> go get -u github.com/jcouture/nv

You create a .env file as follows:

PORT=4200
SECRET_KEY_BASE=3b4476c0f6793b575050a1241438c32de8cbd3b7dec67910369657e1c4c41785
# Comments are supported
DATABASE_URL=postgres://dbuser:@localhost:5432/playground_dev?pool=10

You are ready to use nv to load your context specific environment variables

~> nv .env rails server -p 2808

It is possible to load multiple .env files by separating each filenames with a comma. If a variable exists in more than one file, its value will simply be overriden as parsing goes.

~> nv .env,.env.dev rails server -p 2808

You might need to have global environment variables, overriding context specific ones. Create a file named ~/.nv at the root of your home directory. It has the same format, and will be loaded last.

nv is released under the MIT license. See LICENSE for details.