Environment variable composition and activation layer for tools and processes.
envstack is what
.envfiles wish they were when they grew up.
- Hierarchical environment composition
- Explicit precedence and overrides
- Late-bound environment activation
- Shared, policy-driven environments
- Inspectable and deterministic behavior
envstack environments are layered explicitly. Stack files identify what is being configured, directories identify scope, and ordering determines precedence.
flowchart LR
default[default.env] --> prod[prod.env]
prod --> dev[dev.env]
prod --> test[test.env]
Later layers override earlier ones within the resolved stack. Across
directories, ENVPATH ordering defines precedence: earlier paths win when the
same stack exists in multiple locations. Use envstack -t VAR to trace where a
value comes from. envstack focuses on configuration and activation, not dependency
resolution.
For the core concepts, see docs/index.md.
The easiest way to install:
pip install -U envstackStart by getting the latest default.env example file:
curl -o \
default.env \
https://raw.githubusercontent.com/rsgalloway/envstack/master/examples/default/default.envRunning envstack will launch a new shell session with the resolved environment:
$ envstack
🚀 Launching envstack shell... (CTRL+D or "exit" to quit)
(prod) ~$ echo $ENV
prodTo inspect the unresolved environment (before variable expansion):
$ envstack -u
DEPLOY_ROOT=${ROOT}/${ENV}
ENV=prod
ENVPATH=${DEPLOY_ROOT}/env:${ENVPATH}
LOG_LEVEL=${LOG_LEVEL:=INFO}
PATH=${DEPLOY_ROOT}/bin:${PATH}
PS1=\[\e[32m\](${ENV})\[\e[0m\] \w\$
PYTHONPATH=${DEPLOY_ROOT}/lib/python:${PYTHONPATH}
ROOT=/mnt/pipe
STACK=default$ envstack -r DEPLOY_ROOT
DEPLOY_ROOT=/mnt/pipe/prodenvstack discovers environment definitions via the ENVPATH environment variable.
ENVPATH is to envstack what PATH is to executables:
ENVPATH=/path/to/dev/env:/path/to/prod/envENVPATH ordering defines precedence. Earlier paths win when the same stack
exists in multiple locations, so a stack found in /path/to/dev/env overrides
the same stack found in /path/to/prod/env.
As a rule of thumb:
Files identify stacks; directories identify scope;
ENVPATHdefines precedence.
Convert existing .env files to envstack by piping them into envstack:
cat .env | envstack --set -o out.envTo run any command line executable inside of an environment stack, where
[COMMAND] is the command to run:
$ envstack [STACK] -- [COMMAND]For example:
$ envstack -- echo {ENV}
prodExample of injecting environment into a subprocess:
$ echo "console.log('Hello ' + process.env.ENV)" > index.js
$ node index.js
Hello undefined
$ envstack -- node index.js
Hello prodenvstack supports optional encryption of environment values when writing environment files, allowing sensitive configuration to be safely stored, committed, or distributed.
Encryption protects values at rest and integrates with environment stacks and includes. envstack does not attempt to be a full secret management system.
See docs/secrets.md for details.