Render is a Go library that provides a flexible rendering layer for web applications, supporting multiple output formats including JSON, XML, HTML, text, and binary data. It abstracts away the complexities of marshaling data, setting appropriate content types and headers, and executing HTML templates with support for layouts, partials, and custom template functions. The library is designed to work with any Go web framework by accepting an http.ResponseWriter. The architecture centers around a Render struct that holds configuration and compiled templates, with different renderer types (JSON, XML, HTML, etc.) implementing a common Engine interface. Notable features include automatic template recompilation in development mode, buffer pooling for efficient HTML rendering, streaming JSON output options, and a lock-free implementation by default with optional mutex locking for thread safety. The library also provides filesystem abstraction to support loading templates from disk, embedded files, or custom asset functions.