Environments

pm3 supports environment-specific configuration, letting you override environment variables per deployment target (e.g., production, staging).

Syntax

Define environment overrides as sub-tables named [process.env_<environment>]:

[api]
command = "node server.js"
env = { PORT = "3000", DATABASE_URL = "postgres://localhost/dev" }

[api.env_production]
DATABASE_URL = "postgres://prod-host/mydb"
NODE_ENV = "production"

[api.env_staging]
DATABASE_URL = "postgres://staging-host/mydb"
NODE_ENV = "staging"

Usage

Activate an environment with the --env flag:

pm3 start --env production

This starts all processes with their base env merged with the environment-specific overrides.

Merge Behavior

Environment-specific variables are merged with the base env table:

• Variables defined in the environment override override their base values.
• Variables in the base env that aren't overridden are preserved.
• New variables defined only in the environment override are added.

Using the example above, pm3 start --env production would result in:

Example

[web]
command = "npm start"
env = { PORT = "3000", API_URL = "http://localhost:8080" }

[web.env_production]
API_URL = "https://api.example.com"

[api]
command = "python app.py"
env = { PORT = "8080", DEBUG = "true" }

[api.env_production]
DEBUG = "false"
PORT = "80"

# Development (default)
pm3 start

# Production
pm3 start --env production