diff --git a/.swiftpm/xcode/xcuserdata/holliday.xcuserdatad/xcschemes/xcschememanagement.plist b/.swiftpm/xcode/xcuserdata/holliday.xcuserdatad/xcschemes/xcschememanagement.plist
new file mode 100644
index 000000000..ac9ec027e
--- /dev/null
+++ b/.swiftpm/xcode/xcuserdata/holliday.xcuserdatad/xcschemes/xcschememanagement.plist
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>SchemeUserState</key>
+	<dict>
+		<key>manifold.xcscheme_^#shared#^_</key>
+		<dict>
+			<key>orderHint</key>
+			<integer>0</integer>
+		</dict>
+	</dict>
+</dict>
+</plist>
diff --git a/Package.resolved b/Package.resolved
new file mode 100644
index 000000000..be64744a6
--- /dev/null
+++ b/Package.resolved
@@ -0,0 +1,33 @@
+{
+  "originHash" : "3e2f64f29576d5c20d33a6b24091e7d829288ea5ac3d2f3c511a81a1b60bbab2",
+  "pins" : [
+    {
+      "identity" : "clipper2",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/audulus/Clipper2",
+      "state" : {
+        "branch" : "spm",
+        "revision" : "73a65374f4fec1682bf6af8855e177aa1b02ea3c"
+      }
+    },
+    {
+      "identity" : "glm",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/audulus/glm",
+      "state" : {
+        "branch" : "spm",
+        "revision" : "ad839f90fcd1e630ae134d12b0f21c1d80c58271"
+      }
+    },
+    {
+      "identity" : "tbb-spm",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/audulus/tbb-spm",
+      "state" : {
+        "branch" : "main",
+        "revision" : "3b7877905112736ef6143e990ac9f07434d0abdf"
+      }
+    }
+  ],
+  "version" : 3
+}
diff --git a/Package.swift b/Package.swift
new file mode 100644
index 000000000..8ef2d57fe
--- /dev/null
+++ b/Package.swift
@@ -0,0 +1,31 @@
+// swift-tools-version:5.10
+import PackageDescription
+
+let package = Package(
+    name: "manifold",
+    platforms: [
+        .macOS(.v11), .iOS(.v13)
+    ],
+    products: [
+        .library(
+            name: "manifold",
+            targets: ["manifold"])
+    ],
+    dependencies: [
+        .package(url: "https://github.com/audulus/glm", branch: "spm"),
+        .package(url: "https://github.com/audulus/Clipper2", branch: "spm"),
+        .package(url: "https://github.com/audulus/tbb-spm", branch: "main"),
+    ],
+    targets: [
+        .target(
+            name: "manifold",
+            dependencies: ["glm", "Clipper2", .product(name: "tbb", package: "tbb-spm")],
+            path: "src",
+            publicHeadersPath: "include",
+            cxxSettings: [
+                .define("MANIFOLD_PAR", to: "'T'"),
+            ]
+        )
+    ],
+    cxxLanguageStandard: .cxx20
+)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 52f079f5d..a67100b98 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -12,10 +12,70 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-add_subdirectory(utilities)
-add_subdirectory(collider)
-if(MANIFOLD_CROSS_SECTION)
-    add_subdirectory(cross_section)
+project(manifold)
+
+add_library(${PROJECT_NAME} INTERFACE)
+message("Parallel Backend: ${MANIFOLD_PAR}")
+
+include(FetchContent)
+if (TRACY_ENABLE)
+    include(FetchContent)
+    FetchContent_Declare(tracy
+        GIT_REPOSITORY https://github.com/wolfpld/tracy.git
+        GIT_TAG v0.10
+        GIT_SHALLOW TRUE
+        GIT_PROGRESS TRUE
+    )
+    FetchContent_MakeAvailable(tracy)
+    target_link_libraries(${PROJECT_NAME} INTERFACE TracyClient)
+endif()
+
+if(MANIFOLD_PAR STREQUAL "TBB")
+    target_compile_options(${PROJECT_NAME} INTERFACE -DMANIFOLD_PAR='T')
+    if(TARGET TBB::tbb)
+        target_link_libraries(${PROJECT_NAME} INTERFACE TBB::tbb)
+    else()
+        target_include_directories(${PROJECT_NAME} INTERFACE $<BUILD_INTERFACE:${TBB_INCLUDE_DIRS}>)
+        target_link_libraries(${PROJECT_NAME} INTERFACE ${TBB_LINK_LIBRARIES})
+    endif()
+    if(APPLE)
+        if(oneDPL_FOUND)
+            target_link_libraries(${PROJECT_NAME} INTERFACE oneDPL)
+        else()
+            message(WARNING "oneDPL not found, sequential implementation is used instead")
+        endif()
+    endif()
+elseif(MANIFOLD_PAR STREQUAL "NONE")
+    set(MANIFOLD_PAR "CPP")
+else()
+    message(FATAL_ERROR "Invalid value for MANIFOLD_PAR: ${MANIFOLD_PAR}. "
+        "Should be \"TBB\" or \"NONE\"")
 endif()
-add_subdirectory(polygon)
-add_subdirectory(manifold)
+
+target_include_directories(${PROJECT_NAME} INTERFACE
+    $<INSTALL_INTERFACE:include>
+    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
+target_link_libraries(${PROJECT_NAME} INTERFACE glm::glm)
+
+if(MANIFOLD_EXCEPTIONS)
+    target_compile_options(${PROJECT_NAME} INTERFACE
+        -DMANIFOLD_EXCEPTIONS=1
+    )
+endif()
+
+if(MANIFOLD_DEBUG)
+    target_compile_options(${PROJECT_NAME}
+        INTERFACE -DMANIFOLD_DEBUG)
+endif()
+
+target_compile_features(${PROJECT_NAME} INTERFACE cxx_std_17)
+
+install(TARGETS ${PROJECT_NAME} EXPORT manifoldTargets)
+install(FILES
+    include/manifold/common.h
+    include/manifold/vec_view.h
+    include/manifold/tri_dist.h
+    include/manifold/optional_assert.h
+    include/manifold/iters.h
+    include/manifold/parallel.h
+    DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_PROJECT_NAME})
diff --git a/src/manifold/src/boolean3.cpp b/src/boolean3.cpp
similarity index 100%
rename from src/manifold/src/boolean3.cpp
rename to src/boolean3.cpp
diff --git a/src/manifold/src/boolean3.h b/src/boolean3.h
similarity index 100%
rename from src/manifold/src/boolean3.h
rename to src/boolean3.h
diff --git a/src/manifold/src/boolean_result.cpp b/src/boolean_result.cpp
similarity index 100%
rename from src/manifold/src/boolean_result.cpp
rename to src/boolean_result.cpp
diff --git a/src/collider/CMakeLists.txt b/src/collider/CMakeLists.txt
deleted file mode 100644
index 2f5d20a25..000000000
--- a/src/collider/CMakeLists.txt
+++ /dev/null
@@ -1,23 +0,0 @@
-# Copyright 2020 The Manifold Authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     https://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-project (collider)
-
-add_library(${PROJECT_NAME} INTERFACE)
-target_include_directories(${PROJECT_NAME} INTERFACE
-    $<INSTALL_INTERFACE:include>
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
-target_link_libraries(${PROJECT_NAME} INTERFACE utilities)
-target_compile_options(${PROJECT_NAME} INTERFACE ${MANIFOLD_FLAGS})
-target_compile_features(${PROJECT_NAME} INTERFACE cxx_std_17)
diff --git a/src/manifold/src/constructors.cpp b/src/constructors.cpp
similarity index 100%
rename from src/manifold/src/constructors.cpp
rename to src/constructors.cpp
diff --git a/src/cross_section/src/cross_section.cpp b/src/cross_section.cpp
similarity index 100%
rename from src/cross_section/src/cross_section.cpp
rename to src/cross_section.cpp
diff --git a/src/cross_section/CMakeLists.txt b/src/cross_section/CMakeLists.txt
deleted file mode 100644
index 600a40b46..000000000
--- a/src/cross_section/CMakeLists.txt
+++ /dev/null
@@ -1,36 +0,0 @@
-# Copyright 2023 The Manifold Authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     https://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-project (cross_section)
-file(GLOB_RECURSE SOURCE_FILES CONFIGURE_DEPENDS *.cpp)
-add_library(${PROJECT_NAME} ${SOURCE_FILES})
-target_include_directories(${PROJECT_NAME} PUBLIC
-    $<INSTALL_INTERFACE:include>
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
-
-if(TARGET Clipper2::Clipper2)
-    target_link_libraries(${PROJECT_NAME}
-        PUBLIC utilities
-        PRIVATE Clipper2::Clipper2)
-else()
-    target_link_libraries(${PROJECT_NAME}
-        PUBLIC utilities
-        PRIVATE Clipper2)
-endif()
-
-target_compile_options(${PROJECT_NAME} PRIVATE ${MANIFOLD_FLAGS})
-target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_17)
-
-install(TARGETS ${PROJECT_NAME} EXPORT manifoldTargets)
-install(FILES include/manifold/cross_section.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_PROJECT_NAME})
diff --git a/src/manifold/src/csg_tree.cpp b/src/csg_tree.cpp
similarity index 100%
rename from src/manifold/src/csg_tree.cpp
rename to src/csg_tree.cpp
diff --git a/src/manifold/src/csg_tree.h b/src/csg_tree.h
similarity index 100%
rename from src/manifold/src/csg_tree.h
rename to src/csg_tree.h
diff --git a/src/manifold/src/edge_op.cpp b/src/edge_op.cpp
similarity index 100%
rename from src/manifold/src/edge_op.cpp
rename to src/edge_op.cpp
diff --git a/src/manifold/src/face_op.cpp b/src/face_op.cpp
similarity index 100%
rename from src/manifold/src/face_op.cpp
rename to src/face_op.cpp
diff --git a/src/manifold/src/impl.cpp b/src/impl.cpp
similarity index 100%
rename from src/manifold/src/impl.cpp
rename to src/impl.cpp
diff --git a/src/manifold/src/impl.h b/src/impl.h
similarity index 100%
rename from src/manifold/src/impl.h
rename to src/impl.h
diff --git a/src/collider/include/manifold/collider.h b/src/include/manifold/collider.h
similarity index 100%
rename from src/collider/include/manifold/collider.h
rename to src/include/manifold/collider.h
diff --git a/src/utilities/include/manifold/common.h b/src/include/manifold/common.h
similarity index 100%
rename from src/utilities/include/manifold/common.h
rename to src/include/manifold/common.h
diff --git a/src/cross_section/include/manifold/cross_section.h b/src/include/manifold/cross_section.h
similarity index 100%
rename from src/cross_section/include/manifold/cross_section.h
rename to src/include/manifold/cross_section.h
diff --git a/src/utilities/include/manifold/hashtable.h b/src/include/manifold/hashtable.h
similarity index 100%
rename from src/utilities/include/manifold/hashtable.h
rename to src/include/manifold/hashtable.h
diff --git a/src/utilities/include/manifold/iters.h b/src/include/manifold/iters.h
similarity index 100%
rename from src/utilities/include/manifold/iters.h
rename to src/include/manifold/iters.h
diff --git a/src/manifold/include/manifold/manifold.h b/src/include/manifold/manifold.h
similarity index 100%
rename from src/manifold/include/manifold/manifold.h
rename to src/include/manifold/manifold.h
diff --git a/src/utilities/include/manifold/optional_assert.h b/src/include/manifold/optional_assert.h
similarity index 100%
rename from src/utilities/include/manifold/optional_assert.h
rename to src/include/manifold/optional_assert.h
diff --git a/src/utilities/include/manifold/parallel.h b/src/include/manifold/parallel.h
similarity index 100%
rename from src/utilities/include/manifold/parallel.h
rename to src/include/manifold/parallel.h
diff --git a/src/polygon/include/manifold/polygon.h b/src/include/manifold/polygon.h
similarity index 100%
rename from src/polygon/include/manifold/polygon.h
rename to src/include/manifold/polygon.h
diff --git a/src/utilities/include/manifold/sparse.h b/src/include/manifold/sparse.h
similarity index 100%
rename from src/utilities/include/manifold/sparse.h
rename to src/include/manifold/sparse.h
diff --git a/src/utilities/include/manifold/svd.h b/src/include/manifold/svd.h
similarity index 100%
rename from src/utilities/include/manifold/svd.h
rename to src/include/manifold/svd.h
diff --git a/src/utilities/include/manifold/tri_dist.h b/src/include/manifold/tri_dist.h
similarity index 100%
rename from src/utilities/include/manifold/tri_dist.h
rename to src/include/manifold/tri_dist.h
diff --git a/src/utilities/include/manifold/utils.h b/src/include/manifold/utils.h
similarity index 100%
rename from src/utilities/include/manifold/utils.h
rename to src/include/manifold/utils.h
diff --git a/src/utilities/include/manifold/vec.h b/src/include/manifold/vec.h
similarity index 100%
rename from src/utilities/include/manifold/vec.h
rename to src/include/manifold/vec.h
diff --git a/src/utilities/include/manifold/vec_view.h b/src/include/manifold/vec_view.h
similarity index 100%
rename from src/utilities/include/manifold/vec_view.h
rename to src/include/manifold/vec_view.h
diff --git a/src/manifold/src/manifold.cpp b/src/manifold.cpp
similarity index 100%
rename from src/manifold/src/manifold.cpp
rename to src/manifold.cpp
diff --git a/src/manifold/CMakeLists.txt b/src/manifold/CMakeLists.txt
deleted file mode 100644
index 00136b5da..000000000
--- a/src/manifold/CMakeLists.txt
+++ /dev/null
@@ -1,35 +0,0 @@
-# Copyright 2020 The Manifold Authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     https://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-project (manifold)
-
-file(GLOB_RECURSE SOURCE_FILES CONFIGURE_DEPENDS *.cpp)
-add_library(${PROJECT_NAME} ${SOURCE_FILES})
-
-target_include_directories(${PROJECT_NAME} PUBLIC
-    $<INSTALL_INTERFACE:include>
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
-target_link_libraries(${PROJECT_NAME}
-    PUBLIC utilities
-    PRIVATE $<BUILD_INTERFACE:collider> polygon ${MANIFOLD_INCLUDE}
-)
-
-target_compile_options(${PROJECT_NAME} PRIVATE ${MANIFOLD_FLAGS})
-
-target_compile_features(${PROJECT_NAME}
-    PUBLIC cxx_std_17
-)
-
-install(TARGETS ${PROJECT_NAME} EXPORT manifoldTargets)
-install(FILES include/manifold/manifold.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_PROJECT_NAME})
diff --git a/src/manifold/src/mesh_fixes.h b/src/mesh_fixes.h
similarity index 100%
rename from src/manifold/src/mesh_fixes.h
rename to src/mesh_fixes.h
diff --git a/src/polygon/src/polygon.cpp b/src/polygon.cpp
similarity index 100%
rename from src/polygon/src/polygon.cpp
rename to src/polygon.cpp
diff --git a/src/polygon/CMakeLists.txt b/src/polygon/CMakeLists.txt
deleted file mode 100644
index 44338336d..000000000
--- a/src/polygon/CMakeLists.txt
+++ /dev/null
@@ -1,31 +0,0 @@
-# Copyright 2020 The Manifold Authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     https://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-project (polygon)
-
-file(GLOB_RECURSE SOURCE_FILES CONFIGURE_DEPENDS *.cpp)
-add_library(${PROJECT_NAME} ${SOURCE_FILES})
-target_include_directories(${PROJECT_NAME} PUBLIC
-    $<INSTALL_INTERFACE:include>
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
-target_link_libraries(${PROJECT_NAME} 
-    PUBLIC utilities 
-    PRIVATE $<BUILD_INTERFACE:collider>
-)
-
-target_compile_options(${PROJECT_NAME} PRIVATE ${MANIFOLD_FLAGS})
-target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_17)
-
-install(TARGETS ${PROJECT_NAME} EXPORT manifoldTargets)
-install(FILES include/manifold/polygon.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_PROJECT_NAME})
diff --git a/src/manifold/src/properties.cpp b/src/properties.cpp
similarity index 100%
rename from src/manifold/src/properties.cpp
rename to src/properties.cpp
diff --git a/src/manifold/src/quickhull.cpp b/src/quickhull.cpp
similarity index 100%
rename from src/manifold/src/quickhull.cpp
rename to src/quickhull.cpp
diff --git a/src/manifold/src/quickhull.h b/src/quickhull.h
similarity index 100%
rename from src/manifold/src/quickhull.h
rename to src/quickhull.h
diff --git a/src/manifold/src/sdf.cpp b/src/sdf.cpp
similarity index 100%
rename from src/manifold/src/sdf.cpp
rename to src/sdf.cpp
diff --git a/src/manifold/src/shared.h b/src/shared.h
similarity index 100%
rename from src/manifold/src/shared.h
rename to src/shared.h
diff --git a/src/manifold/src/smoothing.cpp b/src/smoothing.cpp
similarity index 100%
rename from src/manifold/src/smoothing.cpp
rename to src/smoothing.cpp
diff --git a/src/manifold/src/sort.cpp b/src/sort.cpp
similarity index 100%
rename from src/manifold/src/sort.cpp
rename to src/sort.cpp
diff --git a/src/manifold/src/subdivision.cpp b/src/subdivision.cpp
similarity index 100%
rename from src/manifold/src/subdivision.cpp
rename to src/subdivision.cpp
diff --git a/src/utilities/CMakeLists.txt b/src/utilities/CMakeLists.txt
deleted file mode 100644
index c973f5352..000000000
--- a/src/utilities/CMakeLists.txt
+++ /dev/null
@@ -1,81 +0,0 @@
-# Copyright 2020 The Manifold Authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# https://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-project(utilities)
-
-add_library(${PROJECT_NAME} INTERFACE)
-message("Parallel Backend: ${MANIFOLD_PAR}")
-
-include(FetchContent)
-if (TRACY_ENABLE)
-    include(FetchContent)
-    FetchContent_Declare(tracy
-        GIT_REPOSITORY https://github.com/wolfpld/tracy.git
-        GIT_TAG v0.10
-        GIT_SHALLOW TRUE
-        GIT_PROGRESS TRUE
-    )
-    FetchContent_MakeAvailable(tracy)
-    target_link_libraries(${PROJECT_NAME} INTERFACE TracyClient)
-endif()
-
-if(MANIFOLD_PAR STREQUAL "TBB")
-    target_compile_options(${PROJECT_NAME} INTERFACE -DMANIFOLD_PAR='T')
-    if(TARGET TBB::tbb)
-        target_link_libraries(${PROJECT_NAME} INTERFACE TBB::tbb)
-    else()
-        target_include_directories(${PROJECT_NAME} INTERFACE $<BUILD_INTERFACE:${TBB_INCLUDE_DIRS}>)
-        target_link_libraries(${PROJECT_NAME} INTERFACE ${TBB_LINK_LIBRARIES})
-    endif()
-    if(APPLE)
-        if(oneDPL_FOUND)
-            target_link_libraries(${PROJECT_NAME} INTERFACE oneDPL)
-        else()
-            message(WARNING "oneDPL not found, sequential implementation is used instead")
-        endif()
-    endif()
-elseif(MANIFOLD_PAR STREQUAL "NONE")
-    set(MANIFOLD_PAR "CPP")
-else()
-    message(FATAL_ERROR "Invalid value for MANIFOLD_PAR: ${MANIFOLD_PAR}. "
-        "Should be \"TBB\" or \"NONE\"")
-endif()
-
-target_include_directories(${PROJECT_NAME} INTERFACE
-    $<INSTALL_INTERFACE:include>
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
-target_link_libraries(${PROJECT_NAME} INTERFACE glm::glm)
-
-if(MANIFOLD_EXCEPTIONS)
-    target_compile_options(${PROJECT_NAME} INTERFACE
-        -DMANIFOLD_EXCEPTIONS=1
-    )
-endif()
-
-if(MANIFOLD_DEBUG)
-    target_compile_options(${PROJECT_NAME}
-        INTERFACE -DMANIFOLD_DEBUG)
-endif()
-
-target_compile_features(${PROJECT_NAME} INTERFACE cxx_std_17)
-
-install(TARGETS ${PROJECT_NAME} EXPORT manifoldTargets)
-install(FILES
-    include/manifold/common.h
-    include/manifold/vec_view.h
-    include/manifold/tri_dist.h
-    include/manifold/optional_assert.h
-    include/manifold/iters.h
-    include/manifold/parallel.h
-    DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_PROJECT_NAME})