> For clean Markdown content of this page, append .md to this URL. For the complete documentation index, see https://buildwithfern.com/learn/llms.txt. ## 0.41.0-rc0 **`(break):`** Every fern folder that is using OpenAPI must configure an explicit location to the OpenAPI spec. The location can be configured in your `generators.yml`: ```yml api: path: path/to/openapi.yml ``` If you run **fern upgrade**, the CLI will automatically run a migration for you to ensure that you are compliant! ## 0.40.4 **`(fix):`** `fern check` allows the service base-path to be a slash. For example, the following would be valid: ```yml service: base-path: "/" ``` ## 0.40.3 **`(fix):`** Now `fern generator upgrade` respects the `--group` flag and only upgrades generators within a particular group.