diff --git a/build_as_lib.py b/build_as_lib.py
index da4337c0..43e06fdd 100644
--- a/build_as_lib.py
+++ b/build_as_lib.py
@@ -6,11 +6,13 @@ menv=env # type: ignore
 src_filter = [
   '+<*.cpp>',
   '+<helpers/*.cpp>',
-  '+<helpers/sensors>'
+  '+<helpers/sensors>',
   '+<helpers/radiolib/*.cpp>',
   '+<helpers/ui/MomentaryButton.cpp>',
 ]
 
+use_display = False
+
 # add build and include dirs according to CPPDEFINES
 for item in menv.get("CPPDEFINES", []):
  
@@ -38,12 +40,25 @@ for item in menv.get("CPPDEFINES", []):
         menv.Append(BUILD_FLAGS=["-I src/helpers/rp2040"])
         src_filter.append("+<helpers/rp2040/*>")
     
+    # DISPLAY HANDLING
+    elif isinstance(item, tuple) and item[0] == "DISPLAY_CLASS":
+        display_class = item[1]
+        use_display = True
+        src_filter.append(f"+<helpers/ui/{display_class}.cpp>")
+        if (display_class == "ST7789Display") :
+            src_filter.append(f"+<helpers/ui/OLEDDisplay.cpp>")
+            src_filter.append(f"+<helpers/ui/OLEDDisplayFonts.cpp>")
+
     # VARIANTS HANDLING
     elif isinstance(item, tuple) and item[0] == "MC_VARIANT":
         variant_name = item[1]
         menv.Append(BUILD_FLAGS=[f"-I variants/{variant_name}"])
         src_filter.append(f"+<../variants/{variant_name}>")
 
+if use_display :
+    menv.Append(CPPPATH=[realpath("src/helpers/ui")])
+    menv.Append(BUILD_FLAGS=["-I src/helpers/ui"])
+
 menv.Replace(SRC_FILTER=src_filter)
 
 #print (menv.Dump())