enable cpphs for conditional compilations

package.yaml

@@ -34,6 +34,9 @@ dependencies:
 - http-types
 - warp
 
+build-tools:
+- cpphs
+
 executables:
   tickLeisteServer:
     main:                Main.hs
@@ -42,6 +45,9 @@ executables:
     - -threaded
     - -rtsopts
     - -with-rtsopts=-N
+    - -cpp
+    - -pgmP cpphs
+    - -optP --cpp
 
 tests:
   tickLeisteServer-test: