diff --git a/cmake/deps/abseil.cmake b/cmake/deps/abseil.cmake
index b1979b71036..0f89f076d7c 100644
--- a/cmake/deps/abseil.cmake
+++ b/cmake/deps/abseil.cmake
@@ -9,6 +9,9 @@ if(NOT TARGET absl::strings)
   block()
     set(BUILD_SHARED_LIBS 0)
     set(BUILD_TESTING 0)
+    # Abseil's .cc files have file-scope statics (kAsciiToInt, ...) that clash
+    # when batched, so it must not be unity-built.
+    set(CMAKE_UNITY_BUILD OFF)
     set(ABSL_BUILD_TESTING OFF CACHE INTERNAL "")
     set(ABSL_PROPAGATE_CXX_STD ON CACHE INTERNAL "")
     # Treat Abseil's headers as system headers so that re2 (and ossia) do not
diff --git a/src/ossia_features.cmake b/src/ossia_features.cmake
index 01026db10cf..be16f23a5fd 100644
--- a/src/ossia_features.cmake
+++ b/src/ossia_features.cmake
@@ -140,8 +140,7 @@ endif()
 
 if(OSSIA_PROTOCOL_WIIMOTE)
   target_sources(ossia PRIVATE ${OSSIA_WIIMOTE_SRCS} ${OSSIA_WIIMOTE_HEADERS})
-  ossia_use_system(use_sys wiiuse)
-  if(NOT use_sys)
+  if(WIIUSE_DIR)
     target_include_directories(ossia PRIVATE "${WIIUSE_DIR}/src")
   endif()
   target_link_libraries(ossia PRIVATE $<BUILD_INTERFACE:wiiuse>)