diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 8b33d19..2f3bf8e 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -61,3 +61,23 @@ jobs:
         test -f build/libdmosi.a
         echo "✓ libdmosi.a created successfully with DMOSI_DONT_IMPLEMENT_DMOD_API=ON"
 
+    - name: Clean for module mode build
+      run: |
+        rm -rf build
+        
+    - name: Configure CMake (DMOD_MODULE mode)
+      run: |
+        mkdir -p build
+        cd build
+        cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -DDMOD_MODE=DMOD_MODULE ..
+        
+    - name: Build (DMOD_MODULE mode)
+      run: |
+        cd build
+        make -j$(nproc)
+        
+    - name: Verify module mode build (no static library)
+      run: |
+        test ! -f build/libdmosi.a
+        echo "✓ libdmosi.a not created in DMOD_MODULE mode (expected)"
+
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 60fc4a3..ff87bf1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -51,41 +51,55 @@ else()
     message(STATUS "dmod target already exists, skipping FetchContent")
 endif()
 
+include(${DMOD_DIR}/paths.cmake)
+
 # ======================================================================
-#               DMOD OSI Library
+#               DMOD OSI Interface Library
 # ======================================================================
 set(MODULE_NAME dmosi)
-add_library(${MODULE_NAME} STATIC
-    src/dmosi.c
-)
 
-target_compile_definitions(${MODULE_NAME} 
-    PRIVATE 
-        $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API}>:DMOSI_DONT_IMPLEMENT_DMOD_API>
-        $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_MUTEX}>:DMOSI_DONT_IMPLEMENT_DMOD_API_MUTEX>
-        $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_ENV}>:DMOSI_DONT_IMPLEMENT_DMOD_API_ENV>
-        $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_PROC}>:DMOSI_DONT_IMPLEMENT_DMOD_API_PROC>
-        $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_TIME}>:DMOSI_DONT_IMPLEMENT_DMOD_API_TIME>
-        DMOSI_VERSION="${PROJECT_VERSION}"
+add_library(dmosi_if INTERFACE)
+target_include_directories(dmosi_if
+    INTERFACE
+        ${CMAKE_CURRENT_SOURCE_DIR}/include
 )
 
-target_include_directories(${MODULE_NAME} 
-    PUBLIC 
-        ${CMAKE_CURRENT_SOURCE_DIR}/include
-)   
+# ======================================================================
+#               DMOD OSI Library (system mode only)
+# ======================================================================
+if(DMOD_SYSTEM)
+    add_library(${MODULE_NAME} STATIC
+        src/dmosi.c
+    )
 
-target_link_libraries(${MODULE_NAME} 
-    PRIVATE    
-        dmod_inc
+    target_compile_definitions(${MODULE_NAME} 
+        PRIVATE 
+            $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API}>:DMOSI_DONT_IMPLEMENT_DMOD_API>
+            $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_MUTEX}>:DMOSI_DONT_IMPLEMENT_DMOD_API_MUTEX>
+            $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_ENV}>:DMOSI_DONT_IMPLEMENT_DMOD_API_ENV>
+            $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_PROC}>:DMOSI_DONT_IMPLEMENT_DMOD_API_PROC>
+            $<$<BOOL:${DMOSI_DONT_IMPLEMENT_DMOD_API_TIME}>:DMOSI_DONT_IMPLEMENT_DMOD_API_TIME>
+            DMOSI_VERSION="${PROJECT_VERSION}"
     )
 
-# Enable coverage for dmosi library if requested
-if(ENABLE_COVERAGE)
-    target_compile_options(${MODULE_NAME} PRIVATE --coverage)
-    target_link_options(${MODULE_NAME} PRIVATE --coverage)
-endif()
+    target_include_directories(${MODULE_NAME} 
+        PUBLIC 
+            ${CMAKE_CURRENT_SOURCE_DIR}/include
+    )   
+
+    target_link_libraries(${MODULE_NAME} 
+        PRIVATE    
+            dmod_inc
+        )
+
+    # Enable coverage for dmosi library if requested
+    if(ENABLE_COVERAGE)
+        target_compile_options(${MODULE_NAME} PRIVATE --coverage)
+        target_link_options(${MODULE_NAME} PRIVATE --coverage)
+    endif()
 
-create_library_makefile(${MODULE_NAME})
+    create_library_makefile(${MODULE_NAME})
+endif()
 
 # ======================================================================
 #               Tests