diff --git a/README/ReleaseNotes/v642/index.md b/README/ReleaseNotes/v642/index.md
index 61c80c9c5b822..c486699e02610 100644
--- a/README/ReleaseNotes/v642/index.md
+++ b/README/ReleaseNotes/v642/index.md
@@ -74,6 +74,7 @@ The `TMVA_SOFIE_GNN` tutorials have been migrated to this workflow and produce i
 * Including `RConfig.h` and `RVersion.h` is now deprecated and will be removed after ROOT 6.44, use instead `ROOT/RConfig.hxx` and `ROOT/RVersion.hxx`.
 * The header `Rpair.h` is deprecated and will be removed after ROOT 6.44, use `<utility>` instead.
 * The headers `Htypes.h` and `Gtypes.h` that were deprecated in ROOT 6.20 will now emit warnings and will be fully removed in ROOT 6.44. Use instead `Rtypes.h`.
+* The headers of the `bvh` library in `Geom` are no longer public in ROOT 6.42.
 * The header `GLConstants.h` is no longer part of ROOT installed headers.
 * The header `PosixThreadInc.h` is deprecated and will be removed after ROOT 6.44. Use instead `<ctime>` and `<cstdlib>`.
 * The header `RStringView.h` deprecated in ROOT 6.14  will now emit warnings and will be fully removed after ROOT 6.44. Use `ROOT/RStringView.hxx` instead.
diff --git a/builtins/bvh/LICENSE.txt b/builtins/bvh/LICENSE.txt
new file mode 100644
index 0000000000000..8fe2274ab8872
--- /dev/null
+++ b/builtins/bvh/LICENSE.txt
@@ -0,0 +1,16 @@
+Copyright 2022 Arsène Pérard-Gayot
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial
+portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
+OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/geom/geom/inc/bvh/v2/CMakeLists.txt b/builtins/bvh/v2/CMakeLists.txt
similarity index 100%
rename from geom/geom/inc/bvh/v2/CMakeLists.txt
rename to builtins/bvh/v2/CMakeLists.txt
diff --git a/geom/geom/inc/bvh/v2/README.md b/builtins/bvh/v2/README.md
similarity index 100%
rename from geom/geom/inc/bvh/v2/README.md
rename to builtins/bvh/v2/README.md
diff --git a/geom/geom/inc/bvh/v2/bbox.h b/builtins/bvh/v2/bbox.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/bbox.h
rename to builtins/bvh/v2/bbox.h
diff --git a/geom/geom/inc/bvh/v2/binned_sah_builder.h b/builtins/bvh/v2/binned_sah_builder.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/binned_sah_builder.h
rename to builtins/bvh/v2/binned_sah_builder.h
diff --git a/geom/geom/inc/bvh/v2/bvh.h b/builtins/bvh/v2/bvh.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/bvh.h
rename to builtins/bvh/v2/bvh.h
diff --git a/geom/geom/inc/bvh/v2/default_builder.h b/builtins/bvh/v2/default_builder.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/default_builder.h
rename to builtins/bvh/v2/default_builder.h
diff --git a/geom/geom/inc/bvh/v2/executor.h b/builtins/bvh/v2/executor.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/executor.h
rename to builtins/bvh/v2/executor.h
diff --git a/geom/geom/inc/bvh/v2/index.h b/builtins/bvh/v2/index.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/index.h
rename to builtins/bvh/v2/index.h
diff --git a/geom/geom/inc/bvh/v2/mini_tree_builder.h b/builtins/bvh/v2/mini_tree_builder.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/mini_tree_builder.h
rename to builtins/bvh/v2/mini_tree_builder.h
diff --git a/geom/geom/inc/bvh/v2/node.h b/builtins/bvh/v2/node.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/node.h
rename to builtins/bvh/v2/node.h
diff --git a/geom/geom/inc/bvh/v2/platform.h b/builtins/bvh/v2/platform.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/platform.h
rename to builtins/bvh/v2/platform.h
diff --git a/geom/geom/inc/bvh/v2/ray.h b/builtins/bvh/v2/ray.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/ray.h
rename to builtins/bvh/v2/ray.h
diff --git a/geom/geom/inc/bvh/v2/reinsertion_optimizer.h b/builtins/bvh/v2/reinsertion_optimizer.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/reinsertion_optimizer.h
rename to builtins/bvh/v2/reinsertion_optimizer.h
diff --git a/geom/geom/inc/bvh/v2/split_heuristic.h b/builtins/bvh/v2/split_heuristic.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/split_heuristic.h
rename to builtins/bvh/v2/split_heuristic.h
diff --git a/geom/geom/inc/bvh/v2/stack.h b/builtins/bvh/v2/stack.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/stack.h
rename to builtins/bvh/v2/stack.h
diff --git a/geom/geom/inc/bvh/v2/stream.h b/builtins/bvh/v2/stream.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/stream.h
rename to builtins/bvh/v2/stream.h
diff --git a/geom/geom/inc/bvh/v2/sweep_sah_builder.h b/builtins/bvh/v2/sweep_sah_builder.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/sweep_sah_builder.h
rename to builtins/bvh/v2/sweep_sah_builder.h
diff --git a/geom/geom/inc/bvh/v2/thread_pool.h b/builtins/bvh/v2/thread_pool.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/thread_pool.h
rename to builtins/bvh/v2/thread_pool.h
diff --git a/geom/geom/inc/bvh/v2/top_down_sah_builder.h b/builtins/bvh/v2/top_down_sah_builder.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/top_down_sah_builder.h
rename to builtins/bvh/v2/top_down_sah_builder.h
diff --git a/geom/geom/inc/bvh/v2/utils.h b/builtins/bvh/v2/utils.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/utils.h
rename to builtins/bvh/v2/utils.h
diff --git a/geom/geom/inc/bvh/v2/vec.h b/builtins/bvh/v2/vec.h
similarity index 100%
rename from geom/geom/inc/bvh/v2/vec.h
rename to builtins/bvh/v2/vec.h
diff --git a/geom/geom/CMakeLists.txt b/geom/geom/CMakeLists.txt
index 71d76e74fb8a1..8d186eb24b20d 100644
--- a/geom/geom/CMakeLists.txt
+++ b/geom/geom/CMakeLists.txt
@@ -130,6 +130,10 @@ ROOT_STANDARD_LIBRARY_PACKAGE(Geom
     Imt
 )
 
+target_include_directories(Geom PRIVATE res
+../../builtins/ # for bvh hard-coded builtin, forked from https://github.com/madmann91/bvh/commit/66e445b92f68801a6dd8ef943fe3038976ecb4ff
+# TODO: move this to a proper isolated builtin with find_package, and resync with upstream version, add ROOT builtin_bvh option 
+)
 # GCC has bugs with -O3 or -Ofast that break Geom
 if(CMAKE_COMPILER_IS_GNUCXX)
   if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5 OR CMAKE_SIZEOF_VOID_P LESS 8)
diff --git a/geom/geom/inc/bvh2_extra_kernels.h b/geom/geom/res/bvh2_extra_kernels.h
similarity index 100%
rename from geom/geom/inc/bvh2_extra_kernels.h
rename to geom/geom/res/bvh2_extra_kernels.h
diff --git a/geom/geom/inc/bvh2_third_party.h b/geom/geom/res/bvh2_third_party.h
similarity index 100%
rename from geom/geom/inc/bvh2_third_party.h
rename to geom/geom/res/bvh2_third_party.h