diff --git a/BUILD.bazel b/BUILD.bazel
index 8e75002..2049b33 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -1,6 +1,10 @@
 # Bazel build rules for Fuzzyc.
 load("@fuzzyc_deps//:requirements.bzl", "requirement")
 
+package(default_visibility = [
+    "//visibility:public",
+])
+
 genrule(
     name = "fuzzyc_cc_module_sources",
     srcs = [
@@ -19,7 +23,11 @@
         "ModuleBaseListener.cpp",
         "ModuleBaseListener.h",
     ],
-    cmd = "$(locations @fuzzyc_deps_antlr4_tools//:rules_python_wheel_entry_point_antlr4) -o $(@D) -Dlanguage=Cpp -package fuzzyc_cc_module $(SRCS)",
+    cmd = " ".join([
+      "$(locations @fuzzyc_deps_antlr4_tools//:rules_python_wheel_entry_point_antlr4) -o",
+      "$(RULEDIR) -Dlanguage=Cpp -package fuzzyc_cc_module $(SRCS);",
+      "find $(RULEDIR) \\( -name *.cpp -o -name *.h \\) -exec cp -n {} $(RULEDIR) \\;",
+    ]),
     tools = [
         requirement("antlr4-tools"),
         "@fuzzyc_deps_antlr4_tools//:rules_python_wheel_entry_point_antlr4",
@@ -44,7 +52,11 @@
         "FunctionBaseListener.cpp",
         "FunctionBaseListener.h",
     ],
-    cmd = "$(locations @fuzzyc_deps_antlr4_tools//:rules_python_wheel_entry_point_antlr4) -o $(@D) -Dlanguage=Cpp -package fuzzyc_cc_function $(SRCS)",
+    cmd = " ".join([
+      "$(locations @fuzzyc_deps_antlr4_tools//:rules_python_wheel_entry_point_antlr4) -o",
+      "$(RULEDIR) -Dlanguage=Cpp -package fuzzyc_cc_function $(SRCS);",
+      "find $(RULEDIR) \\( -name *.cpp -o -name *.h \\) -exec cp -n {} $(RULEDIR) \\;",
+    ]),
     tools = [
         requirement("antlr4-tools"),
         "@fuzzyc_deps_antlr4_tools//:rules_python_wheel_entry_point_antlr4",