docs: document multiple override files support in generators.yml

fern/apis/generators-yml/definition/generators.yml

@@ -167,15 +167,22 @@ types:
       - v1
       - v2
 
+  OverridesSchema:
+    discriminated: false
+    docs: Paths to the overrides configuration. Can be a single path or an array of paths applied sequentially.
+    union:
+      - string
+      - list<string>
+
   APIDefinitionWithOverridesSchema:
     properties:
       path: APIDefinitionPathSchema
       origin:
         type: optional<string>
         docs: The URL of the API definition origin, from which the file should be polled.
       overrides:
-        type: optional<string>
-        docs: Path to the OpenAPI or AsyncAPI overrides
+        type: optional<OverridesSchema>
+        docs: Paths to the overrides configuration. Can be a single path or an array of paths applied sequentially.
       audiences:
         type: optional<list<string>>
         docs: Audiences that you would like to filter to
@@ -190,8 +197,8 @@ types:
         type: string
         docs: The path to the `.proto` directory root (e.g. `proto`).
       overrides:
-        type: optional<string>
-        docs: Path to the overrides configuration
+        type: optional<OverridesSchema>
+        docs: Paths to the overrides configuration. Can be a single path or an array of paths applied sequentially.
       local-generation:
         type: optional<boolean>
         docs: Whether to compile the `.proto` files locally. By default, we generate remotely.
@@ -324,14 +331,14 @@ types:
     properties:
       openapi: string
       origin: optional<string>
-      overrides: optional<string>
+      overrides: optional<OverridesSchema>
       namespace: optional<string>
       settings: optional<OpenAPISettingsSchema>
 
   OpenRPCSpecSchema: 
     properties:   
       openrpc: string
-      overrides: optional<string>
+      overrides: optional<OverridesSchema>
       namespace: optional<string>
 
   AsyncAPISettingsSchema:
@@ -346,7 +353,7 @@ types:
     properties:
       asyncapi: string
       origin: optional<string>
-      overrides: optional<string>
+      overrides: optional<OverridesSchema>
       namespace: optional<string>
       settings: optional<AsyncAPISettingsSchema>
 
@@ -367,4 +374,4 @@ types:
 
   ProtobufSpecSchema:
     properties:
-      proto: ProtobufDefinitionSchema
+      proto: ProtobufDefinitionSchema

fern/products/api-def/pages/overrides.mdx

@@ -58,6 +58,17 @@ api:
     - openapi: spec-file.yml 
       overrides: ./overrides.yml
 ```
+
+You can also specify multiple override files. When multiple paths are provided, overrides are applied sequentially in the order listed:
+
+```yaml title="generators.yml"
+api:
+  specs:
+    - openapi: spec-file.yml 
+      overrides:
+        - ./base-overrides.yml
+        - ./sdk-overrides.yml
+```
 </Step>
 <Step title="Fern combines your spec and overrides">
 Now when you run `fern generate`, Fern combines your original API specification with the overrides file:
@@ -100,6 +111,25 @@ paths:
 </Step>
 </Steps>
 
+## Multiple override files
+
+The `overrides` field accepts a single path or a list of paths. When multiple paths are provided, overrides are applied sequentially in order, with later files taking precedence over earlier ones for conflicting keys. This is useful for:
+
+* Separating vendor-specific SDK customizations from shared API overrides
+* Layering team-specific overrides on top of base configurations
+* Keeping override files small and focused on specific concerns
+
+```yaml title="generators.yml"
+api:
+  specs:
+    - openapi: openapi.yml
+      overrides:
+        - ./base-overrides.yml     # Shared overrides (e.g., SDK method names)
+        - ./team-overrides.yml     # Team-specific customizations
+```
+
+Multiple override files are supported for all spec types: OpenAPI, AsyncAPI, OpenRPC, and Protobuf.
+
 ## Separate overrides for SDKs and docs
 
 <Markdown src="/snippets/separate-sdks-docs.mdx" type="overrides" />

fern/products/sdks/reference/generators-yml-reference.mdx

@@ -221,7 +221,7 @@ api:
   specs:
     - asyncapi: "./asyncapi.yml"
       origin: "https://api.example.com/asyncapi.json"
-      overrides: "./asyncapi-overrides.yml"
+      overrides: "./asyncapi-overrides.yml" # or a list of paths
       namespace: "events"
       settings:
         message-naming: "v2"
@@ -237,8 +237,18 @@ api:
   URL of the API definition origin for pulling updates.
 </ParamField>
 
-<ParamField path="overrides" type="string" toc={true}>
-  Path to AsyncAPI overrides file.
+<ParamField path="overrides" type="string | list of strings" toc={true}>
+  Path to an AsyncAPI [overrides](/learn/api-definitions/overview/overrides) file, or a list of paths to multiple override files applied sequentially.
+
+  ```yaml
+  # Single override file
+  overrides: ./asyncapi-overrides.yml
+
+  # Multiple override files (applied in order)
+  overrides:
+    - ./base-overrides.yml
+    - ./sdk-overrides.yml
+  ```
 </ParamField>
 
 <ParamField path="namespace" type="string" toc={true}>
@@ -287,8 +297,18 @@ api:
   Path to the OpenRPC specification file.
 </ParamField>
 
-<ParamField path="overrides" type="string" toc={true}>
-  Path to OpenRPC overrides file.
+<ParamField path="overrides" type="string | list of strings" toc={true}>
+  Path to an OpenRPC [overrides](/learn/api-definitions/overview/overrides) file, or a list of paths to multiple override files applied sequentially.
+
+  ```yaml
+  # Single override file
+  overrides: ./overrides.yml
+
+  # Multiple override files (applied in order)
+  overrides:
+    - ./base-overrides.yml
+    - ./sdk-overrides.yml
+  ```
 </ParamField>
 
 <ParamField path="namespace" type="string" toc={true}>

fern/snippets/grpc-specs.mdx

@@ -15,8 +15,18 @@ api:
   Path to the target `.proto` file (e.g., `proto/user/v1/user.proto`). Omit to generate docs for the entire root folder. 
 </ParamField>
 
-<ParamField path="overrides" type="string" toc={true}>
-  Path to the overrides configuration file. Used for SDK generation only, not for documentation generation.
+<ParamField path="overrides" type="string | list of strings" toc={true}>
+  Path to the overrides configuration file, or a list of paths to multiple override files applied sequentially. Used for SDK generation only, not for documentation generation.
+
+  ```yaml
+  # Single override file
+  overrides: ./overrides.yml
+
+  # Multiple override files (applied in order)
+  overrides:
+    - ./base-overrides.yml
+    - ./sdk-overrides.yml
+  ```
 </ParamField>
 
 <ParamField path="local-generation" type="boolean" default="false" toc={true}>

fern/snippets/openapi-specs.mdx

@@ -4,7 +4,7 @@ api:
     - openapi: "./openapi.yml"
       origin: "https://api.example.com/openapi.json"
       overlays: "./openapi-overlays.yml"
-      overrides: "./openapi-overrides.yml"
+      overrides: "./openapi-overrides.yml" # or a list of paths
       namespace: "v1"
       settings:
         title-as-schema-name: true
@@ -30,8 +30,18 @@ api:
   Path to an [OpenAPI Overlay](/learn/api-definitions/openapi/overlays) file. Overlays follow the [OpenAPI Overlay Specification](https://spec.openapis.org/overlay/v1.0.0.html) and are the recommended approach for customizing OpenAPI specifications.
 </ParamField>
 
-<ParamField path="overrides" type="string" toc={true}>
-  Path to OpenAPI overrides file. Consider using `overlays` instead for a standards-based approach.
+<ParamField path="overrides" type="string | list of strings" toc={true}>
+  Path to an OpenAPI [overrides](/learn/api-definitions/overview/overrides) file, or a list of paths to multiple override files applied sequentially. Consider using `overlays` instead for a standards-based approach.
+
+  ```yaml
+  # Single override file
+  overrides: ./overrides.yml
+
+  # Multiple override files (applied in order)
+  overrides:
+    - ./base-overrides.yml
+    - ./sdk-overrides.yml
+  ```
 </ParamField>
 
 <ParamField path="namespace" type="string" toc={true}>