---
title: env
description: Reference for the env config scope, which defines environment variables that are exported into the environment where tasks are executed.
---

# `env`

The `env` scope defines environment variables that are exported into the environment where tasks are executed.

Prefix each variable name with the `env` scope or surround them by curly brackets, as shown below:

```groovy
env.ALPHA = 'some value'
env.BETA = "$HOME/some/path"

env {
     DELTA = 'one more'
     GAMMA = "/my/path:$PATH"
}
```

:::note
In the above example, variables like `$HOME` and `$PATH` are evaluated when the workflow is launched. If you want these variables to be evaluated during task execution, escape them with `\$`. This difference is important for variables like `$PATH`, which may be different in the workflow environment versus the task environment.
:::

:::warning
The `env` scope provides environment variables to *tasks*, not Nextflow itself. Nextflow environment variables such as `NXF_VER` should be set in the environment in which Nextflow is launched.
:::
