Imagine you're building a Go application that needs a database connection string, an API key for a third-party service, and a secret for signing JSON Web Tokens (JWT). You could hardcode these values directly into your code. This is the first mistake most developers learn to avoid. Hardcoding secrets is a massive security risk, especially if you ever push your code to a public repository like GitHub.
: Different developers have different local setups. One might have a MySQL database on port 3306, while another uses PostgreSQL on port 5432. One might use a local API mock, and another might use a paid sandbox account. A shared, untracked .env.go.local file is non-existent. By each developer maintaining their own .env.go.local , everyone can work with their own credentials without constantly editing (and accidentally committing) a shared config file. Tools like swapenv , a Go CLI application, can even help you easily toggle between multiple .env files as you switch between branches or tasks. .env.go.local
files are often committed to version control to provide default values, files ending in are meant for your eyes only. Local Overrides Imagine you're building a Go application that needs