| NC_TOOL_DIR | App directory to keep metadata and app related files | Defaults to current working directory. In docker maps to `/usr/app/data/` for mounting volume. |
| NC_PUBLIC_URL | Used for sending Email invitations | Best guess from http request params |
| NC_JWT_EXPIRES_IN | JWT token expiry time | `10h` |
| NC_INVITE_ONLY_SIGNUP | Removed since version 0.99.0 and now it's recommended to use [super admin settings menu](/setup-and-usages/account-settings#enable--disable-signup). Allow users to signup only via invite url, value should be any non-empty string. | |
| NUXT_PUBLIC_NC_BACKEND_URL | Custom Backend URL | ``http://localhost:8080`` will be used |
| NC_REQUEST_BODY_SIZE | Request body size [limit](https://expressjs.com/en/resources/middleware/body-parser.html#limit) | `1048576` |
| NC_EXPORT_MAX_TIMEOUT | After NC_EXPORT_MAX_TIMEOUT csv gets downloaded in batches | Default value 5000(in millisecond) will be used |
| NC_DISABLE_CACHE | To be used only while debugging. On setting this to `true` - meta data be fetched from db instead of redis/cache. | `false` |
| AWS_ACCESS_KEY_ID | For Litestream - S3 access key id | If Litestream is configured and `NC_DB` is not present. SQLite gets backed up to S3 |
| AWS_SECRET_ACCESS_KEY | For Litestream - S3 secret access key | If Litestream is configured and `NC_DB` is not present. SQLite gets backed up to S3 |
| AWS_BUCKET | For Litestream - S3 bucket | If Litestream is configured and `NC_DB` is not present. SQLite gets backed up to S3 |
| AWS_BUCKET_PATH | For Litestream - S3 bucket path (like folder within S3 bucket) | If Litestream is configured and `NC_DB` is not present. SQLite gets backed up to S3 |
| NC_SMTP_HOST | For SMTP plugin - SMTP host value | |
| NC_SMTP_PORT | For SMTP plugin - SMTP port value | |
| NC_SMTP_USERNAME | For SMTP plugin (Optional) - SMTP username value for authentication | |
| NC_SMTP_PASSWORD | For SMTP plugin (Optional) - SMTP password value for authentication | |
| NC_SMTP_SECURE | For SMTP plugin (Optional) - To enable secure set value as `true` any other value treated as false | |
| NC_SMTP_IGNORE_TLS | For SMTP plugin (Optional) - To ignore tls set value as `true` any other value treated as false. For more info visit https://nodemailer.com/smtp/ | |
| NC_S3_BUCKET_NAME | For S3 storage plugin - AWS S3 bucket name | |
| NC_S3_REGION | For S3 storage plugin - AWS S3 region | |
| NC_S3_ACCESS_KEY | For S3 storage plugin - AWS access key credential for accessing resource | |
| NC_S3_ACCESS_SECRET | For S3 storage plugin - AWS access secret credential for accessing resource | |
| NC_ADMIN_EMAIL | For updating/creating super admin with provided email and password | |
| NC_ATTACHMENT_FIELD_SIZE | For setting the attachment field size(in Bytes) | Defaults to 20MB |
| NC_ADMIN_PASSWORD | For updating/creating super admin with provided email and password. Your password should have at least 8 letters with one uppercase, one number and one special letter(Allowed special chars $&+,:;=?@#\|'.^*()%!_-" ) | |
| NODE_OPTIONS | For passing Node.js [options](https://nodejs.org/api/cli.html#node_optionsoptions) to instance | |
| NC_MINIMAL_DBS | Create a new SQLite file for each project. All the db files are stored in `nc_minimal_dbs` folder in current working directory. (This option restricts project creation on external sources) | |
| NC_AUTOMATION_LOG_LEVEL | Possible Values: `OFF`, `ERROR`, `ALL`. See [Webhooks](/developer-resources/webhooks#call-log) for details. | `OFF` |
| NC_SECURE_ATTACHMENTS | Allow accessing attachments only through presigned urls. To enable secure set value as `true` any other value treated as false. (⚠ this will make existing links inaccessible ⚠) | `false` |
| NC_ATTACHMENT_EXPIRE_SECONDS | How many seconds before expiring presigned attachment urls. (Attachments will expire in at least set seconds and at most 10mins after set time) | 7200 (2 hours) |
