https://github.com/codeprofis/dymo-cups-drivers/commit/948abc3500f45578a386182c0d2a55bcfcbc2c66.patch

From 948abc3500f45578a386182c0d2a55bcfcbc2c66 Mon Sep 17 00:00:00 2001
From: Florian Knodt <adlerweb@adlerweb.info>
Date: Fri, 28 Feb 2020 23:26:34 +0100
Subject: [PATCH] Add missing backend header. Fixes #11.

---
 src/common/CupsPrintEnvironment.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/common/CupsPrintEnvironment.h b/src/common/CupsPrintEnvironment.h
index 23043d8..76ecefc 100644
--- a/src/common/CupsPrintEnvironment.h
+++ b/src/common/CupsPrintEnvironment.h
@@ -21,6 +21,8 @@
 #ifndef h952b1c81_8931_433a_8479_7ae6d8e85a86
 #define h952b1c81_8931_433a_8479_7ae6d8e85a86
 
+#include <cups/backend.h>
+#include <cups/sidechannel.h>
 #include "PrinterDriver.h"
 
 namespace DymoPrinterDriver