How to: process.env in GO

Environment variables have become a standard for software development, for example popularised by the 12 factor app (3): Config to separate source code and configuration.

For local development we can utilise .env files, in production we usually rely on secrets and other settings to be supplied by our container host.

JavaScript

In Node.js you can read the process environment variables via process.env. Instead of using libraries like dotenv, you can as of node 22 use the --env-file flag to pass a .env file

MY_NAME="Jonathan"

console.log(process.env.MY_NAME)

Example of using the .env file:

node --env-file=.env index.ts

Example .env file:

MY_NAME="Jonathan"

GO

In GO you can read the environment via os.Getenv from the standard library.

MY_NAME=Jonathan go run main.go

package main

import (
  "fmt"
  "os"
)

func main() {
  fmt.Println("MY_NAME:", os.Getenv("MY_NAME"))
}