`std-rfc`, found in the [nushell Repository](https://github.com/nushell/nushell/tree/main/crates/nu-std/std-rfc), serves as a staging ground for possible Standard Library additions.

If you are interested in adding to the Standard Library, please submit your code via PR to the `std-rfc` module in that repository. We also encourage you to install this module and provide feedback on upcoming candidate commands.

::: details More details

Candidate commands for the Standard Library should, in general:

- Have broad appeal - Be useful to a large number of users or use cases
- Be well-written and clearly commented for future maintainers
- Implement help comments with example usage
- Have a description that explains why you feel the command should be a part of the standard library. Think of this as an "advertisement" of sorts to convince people to try the command and provide feedback so that it can be promoted in the future.

In order for a command to be graduated from RFC to the Standard Library, it must have:

- Positive feedback
- Few (or no) outstanding issues and, of course, no significant issues
- A PR author for the `std` submission. This does not necessarily have to be the original author of the command.
- Test cases as part of the `std` submission PR

Ultimately a member of the core team will decide when and if to merge the command into `std` based on these criteria.

Of course, if a candidate command in `std-rfc` no longer works or has too many issues, it may be removed from or disabled in `std-rfc`.

:::

## Disabling the Standard Library

To disable the standard library, you can start Nushell using:

```nu
nu --no-std-lib
```

This can be especially useful to minimize overhead when running a command in a subshell using `nu -c`. For example:

```nu
nu --no-std-lib -n -c "$nu.startup-time"
# => 1ms 125µs 10ns

nu -n -c "$nu.startup-time"
# => 4ms 889µs 576ns
```

You will not be able to import the library, any of its submodules, nor use any of its commands, when it is disabled in this way.

## Using `std/log` in Modules

::: warning Important!
`std/log` exports environment variables. To use the `std/log` module in your own module, please see [this caveat](./modules/creating_modules.md#export-env-runs-only-when-the-use-call-is-evaluated) in the "Creating Modules" Chapter.

:::

## Optimal Startup

If Nushell's startup time is important to your workflow, review your [startup configuration]([./configuration.md]) in `config.nu`, `env.nu`, and potentially others for inefficient use of the standard library. The following command should identify any problem areas:

```nu
view files
| enumerate | flatten
| where filename !~ '^std'
| where filename !~ '^entry'
| where {|file|
    (view span $file.start $file.end) =~ 'use\W+std[^\/]'
  }
```

Edit those files to use the recommended syntax in the [Importing Submodules](#importing-submodules) section above.

::: note
If a Nushell library (e.g., from [the `nu_scripts` repository](https://github.com/nushell/nu_scripts)), example, or doc is using this syntax, please report it via an issue or PR. These will be updated over time after Nushell 0.99.0 is released.

If a third-party module is using this syntax, please report it to the author/maintainers to update.
:::