diff --git a/frontends/CMakeLists.txt b/frontends/CMakeLists.txt
index 6e6eda488..3972fd811 100644
--- a/frontends/CMakeLists.txt
+++ b/frontends/CMakeLists.txt
@@ -6,6 +6,8 @@ add_subdirectory(json)
 add_subdirectory(liberty)
 add_subdirectory(rpc)
 add_subdirectory(rtlil)
-add_subdirectory(slang)
+if (NOT (YOSYS_WITH_PKG_DEPS OR YOSYS_WITHOUT_SLANG))
+    add_subdirectory(slang)
+endif()
 add_subdirectory(verific)
 add_subdirectory(verilog)