diff --git a/core-writer/CMakeLists.txt b/core-writer/CMakeLists.txt
index 45a8b53..58fc515 100644
--- a/core-writer/CMakeLists.txt
+++ b/core-writer/CMakeLists.txt
@@ -1,14 +1,11 @@
-file(GLOB SOURCES
-        src/*.cpp
-        src/compression/*.cpp
-        src/compression/*.c)
+add_subdirectory(external/)
+
+file(GLOB SOURCES src/*.cpp)
 
 add_library(core-writer STATIC ${SOURCES})
 include_directories(core-writer external/)
 
-target_include_directories(core-writer PUBLIC
-        src/
-        src/compression)
+target_include_directories(core-writer PUBLIC src/)
 
 if(CMAKE_BUILD_TYPE STREQUAL "Debug")
     target_compile_definitions(core-writer PRIVATE DEBUG_OUTPUT)
diff --git a/core-writer/external/CMakeLists.txt b/core-writer/external/CMakeLists.txt
new file mode 100644
index 0000000..dc288a0
--- /dev/null
+++ b/core-writer/external/CMakeLists.txt
@@ -0,0 +1,5 @@
+file(GLOB SOURCES bitshuffle/*.c)
+
+add_library(external STATIC ${SOURCES})
+target_include_directories(external PUBLIC .)
+include_directories(/usr/include)
\ No newline at end of file