> ## Documentation Index
> Fetch the complete documentation index at: https://paper.brimble.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Manage environment variables
> Set, edit, and delete environment variables for a project.
Set, edit, and delete environment variables for a project. Variables are injected into both the builder and the running container.
## Prerequisites
* A project deployed on Brimble. If you haven't deployed yet, follow the [quickstart](../getting-started/quickstart).
## Add a variable
1. Open the project.
2. Go to **Environment** in the project sidebar.
3. Pick the environment (Production, Preview, or any custom one) from the dropdown.
4. Click **Add variable**.
5. Enter the name and value. Click **Save**.
The variable is stored encrypted at rest. The next deployment picks it up.
## Add many variables at once
For pasting in a `.env` file:
1. Open **Environment**.
2. Click **Bulk import**.
3. Paste the contents of your `.env` file. Lines starting with `#` are treated as comments.
4. Click **Import**.
Each line of the form `KEY=value` becomes a variable. Quoted values are unquoted. Values containing `=`, `#`, or whitespace should be wrapped in single or double quotes:
```bash theme={null}
KEY=value
QUOTED="value with spaces"
COMMENT_INSIDE='it=is#fine'
```
## Apply changes
Editing variables doesn't redeploy your project automatically. Changes apply on the next deployment:
* Push a new commit to pick them up automatically.
* Or click **Redeploy** on the latest deployment to apply them now.
This is intentional, environment changes are tied to a specific build, so you always know which version of your code is running with which config.
## Edit a variable
In **Environment**, click the variable name. Update the value and save.
## Delete a variable
In **Environment**, click the trash icon next to the variable. Confirm.
## Inherit variables from another environment
A child environment can inherit variables from a parent. Useful when Preview should share most of Production's config but override a few values.
1. Open **Environments** (the tab next to **Environment**).
2. Edit the environment you want to inherit into (e.g. `Preview`).
3. Set **Inherit from** to the parent (e.g. `Production`).
4. Save.
Only variables marked **inheritable** flow through. Toggle the inheritable flag on individual variables in the parent environment.
If a variable is set on both the child and the parent, the child's value wins.
## Reference shared or cross-project variables
A variable's value can include references to other variables, `{{shared.NAME}}` for a shared environment value, or `{{@project-slug.NAME}}` for a value from another project in the same workspace. Brimble resolves these at deploy time so the running container sees the final string.
```bash theme={null}
API_URL={{shared.BASE_URL}}/v1
DATABASE_URL={{@acme-pg-prod.CONNECTION_STRING}}
```
See [Reference shared and cross-project variables](/environments/env-references) for the full syntax, scoping rules, and chaining behavior.
## Build-time vs runtime
**Adding or changing a variable doesn't affect a running deployment.** Variables are injected at build and start time, so the new value takes effect on the next deploy. Click **Redeploy** on the latest deployment after changing env vars, otherwise your container keeps running with the old values.
Variables are injected into the builder and into the running container. Anything you set is available during `install`, `build`, and `start` commands, and your code at runtime reads them like any other process environment variable.
For private package registries, set the auth token as a variable and reference it in `.npmrc` or `pip.conf`:
```ini theme={null}
//registry.npmjs.org/:_authToken=${NPM_TOKEN}
```
## Troubleshooting
**Variable shows in dashboard but not in `process.env`.** You haven't redeployed since adding it. Click **Redeploy** on the latest deployment.
**Variable is set in Production but not in Preview.** Variables are scoped per environment. Either set it in Preview directly, or enable inheritance from Production and mark the variable inheritable.
**Special characters in value get mangled.** When pasting via bulk import, wrap values containing `=`, `#`, or whitespace in quotes: `KEY="value with spaces"`.
**Build fails reading a variable that's set.** If you're using inheritance, the variable might be missing the **inheritable** flag in the parent environment. Check the parent.
## Next steps
* [Environments concept](/environments/overview), how environments and inheritance work.
* [Reference shared and cross-project variables](/environments/env-references), the `{{shared.X}}` and `{{@slug.X}}` syntax.