code: func Error(ctx *neptulon.ReqCtx) error {
  	errored := false
  
  	if err := ctx.Next(); err != nil {
  		errored = true
  		log.Printf("mw: error: error handling response: %v", err)
  	}
  
  	if err := recover(); err != nil {
  		errored = true
  		const size = 64 << 10
  		buf := make([]byte, size)
  		buf = buf[:runtime.Stack(buf, false)]
  		log.Printf("mw: error: panic handling response: %v\nstack trace: %s", err, buf)
  	}
  
  	if errored {
  		if ctx.Err == nil {
  			ctx.Err = &neptulon.ResError{
  				Code:    500,
  				Message: "Internal server error.",
  			}
  		}
  
  		return ctx.Next()
  	}
  
  	return nil
  }
docs: // Error is an error/panic handler middleware.
  // Any error/panic is recovered and logged and the error response is returned to the user (auto-generated if none was set).