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# SDK design

## Docs

- [SDK user features](https://buildwithfern.com/learn/sdks/deep-dives/sdk-user-features.md): Learn about SDK user features in Fern-generated client libraries including installation, error handling, webhook verification, and customization options.
- [Customize README](https://buildwithfern.com/learn/sdks/deep-dives/readme.md): Customize your SDK README with Fern's generators.yml configuration. Add custom sections, control example styles, and organize endpoints by feature.
- [Customize method names](https://buildwithfern.com/learn/sdks/deep-dives/customize-method-names.md): Learn how to customize SDK method names in Fern to create intuitive, user-friendly code. Configure group names and method structures for better API client design.
- [Filter your endpoints (audiences)](https://buildwithfern.com/learn/sdks/deep-dives/audiences.md): Learn how to filter API endpoints using audiences in Fern SDKs. Generate tailored client libraries for internal teams, beta testers, and customers.
- [Server URL templating](https://buildwithfern.com/learn/sdks/deep-dives/server-url-templating.md): Configure server URL templating in Fern SDKs to support dynamic base URLs with variables like region and environment.
- [SSE metadata access](https://buildwithfern.com/learn/sdks/deep-dives/sse-metadata.md): Access server-sent event metadata (event ID, event type, retry interval) in Fern-generated SDKs for stream resumption and protocol-level control.
- [WebSocket clients](https://buildwithfern.com/learn/sdks/deep-dives/websocket-clients.md): Generate typed WebSocket clients in your SDKs for bidirectional communication with connection management, typed messages, and automatic reconnection.
- [Webhook signature verification](https://buildwithfern.com/learn/sdks/deep-dives/webhook-signature-verification.md): Configure webhook signature verification in your Fern-generated SDKs to validate HMAC or asymmetric signatures, protect against replay attacks, and ensure webhook authenticity.
- [XML-encoded types](https://buildwithfern.com/learn/sdks/deep-dives/xml-encoded-types.md): Generate typed XML serializers, parsers, and fluent builders for object types that carry OpenAPI xml metadata, in every Fern SDK.