diff --git a/CMakeLists.txt b/CMakeLists.txt
index 32620d82..71c3a1a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -55,7 +55,7 @@ set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
 FetchContent_MakeAvailable(googletest)
 include(GoogleTest)
 
-add_subdirectory(cmake/project_symlinks)
+add_subdirectory(au)
 
 # Configure how Au will be installed.
 #
diff --git a/au/BUILD.bazel b/au/BUILD.bazel
index c5ca484d..c17a37ca 100644
--- a/au/BUILD.bazel
+++ b/au/BUILD.bazel
@@ -19,7 +19,8 @@ load("@rules_cc//cc:defs.bzl", "cc_library", "cc_test")
 
 cc_library(
     name = "au",
-    hdrs = ["au.hh"],
+    hdrs = ["code/au/au.hh"],
+    includes = ["code"],
     visibility = ["//visibility:public"],
     deps = [
         ":chrono_interop",
@@ -31,7 +32,7 @@ cc_library(
 cc_test(
     name = "au_test",
     size = "small",
-    srcs = ["au_test.cc"],
+    srcs = ["code/au/au_test.cc"],
     deps = [
         ":au",
         ":testing",
@@ -41,7 +42,8 @@ cc_test(
 
 cc_library(
     name = "io",
-    hdrs = ["io.hh"],
+    hdrs = ["code/au/io.hh"],
+    includes = ["code"],
     visibility = ["//visibility:public"],
     deps = [
         ":quantity",
@@ -53,7 +55,7 @@ cc_library(
 cc_test(
     name = "io_test",
     size = "small",
-    srcs = ["io_test.cc"],
+    srcs = ["code/au/io_test.cc"],
     deps = [
         ":io",
         ":prefix",
@@ -64,7 +66,8 @@ cc_test(
 cc_library(
     name = "testing",
     testonly = True,
-    hdrs = ["testing.hh"],
+    hdrs = ["code/au/testing.hh"],
+    includes = ["code"],
     visibility = ["//visibility:public"],
     deps = [
         ":io",
@@ -77,7 +80,7 @@ cc_library(
 cc_test(
     name = "testing_test",
     size = "small",
-    srcs = ["testing_test.cc"],
+    srcs = ["code/au/testing_test.cc"],
     deps = [
         ":testing",
         "@com_google_googletest//:gtest_main",
@@ -86,7 +89,8 @@ cc_test(
 
 cc_library(
     name = "units",
-    hdrs = glob(["units/*.hh"]),
+    hdrs = glob(["code/au/units/*.hh"]),
+    includes = ["code"],
     visibility = ["//visibility:public"],
     deps = [
         ":prefix",
@@ -100,7 +104,7 @@ cc_library(
 cc_test(
     name = "units_test",
     size = "small",
-    srcs = glob(["units/test/*.cc"]),
+    srcs = glob(["code/au/units/test/*.cc"]),
     deps = [
         ":testing",
         ":units",
@@ -113,7 +117,8 @@ cc_test(
 
 cc_library(
     name = "apply_magnitude",
-    hdrs = ["apply_magnitude.hh"],
+    hdrs = ["code/au/apply_magnitude.hh"],
+    includes = ["code"],
     deps = [
         ":apply_rational_magnitude_to_integral",
         ":magnitude",
@@ -123,7 +128,7 @@ cc_library(
 cc_test(
     name = "apply_magnitude_test",
     size = "small",
-    srcs = ["apply_magnitude_test.cc"],
+    srcs = ["code/au/apply_magnitude_test.cc"],
     deps = [
         ":apply_magnitude",
         ":testing",
@@ -133,14 +138,15 @@ cc_test(
 
 cc_library(
     name = "apply_rational_magnitude_to_integral",
-    hdrs = ["apply_rational_magnitude_to_integral.hh"],
+    hdrs = ["code/au/apply_rational_magnitude_to_integral.hh"],
+    includes = ["code"],
     deps = [":magnitude"],
 )
 
 cc_test(
     name = "apply_rational_magnitude_to_integral_test",
     size = "small",
-    srcs = ["apply_rational_magnitude_to_integral_test.cc"],
+    srcs = ["code/au/apply_rational_magnitude_to_integral_test.cc"],
     deps = [
         ":apply_rational_magnitude_to_integral",
         ":testing",
@@ -150,7 +156,8 @@ cc_test(
 
 cc_library(
     name = "chrono_interop",
-    hdrs = ["chrono_interop.hh"],
+    hdrs = ["code/au/chrono_interop.hh"],
+    includes = ["code"],
     deps = [
         ":units",
     ],
@@ -159,7 +166,7 @@ cc_library(
 cc_test(
     name = "chrono_interop_test",
     size = "small",
-    srcs = ["chrono_interop_test.cc"],
+    srcs = ["code/au/chrono_interop_test.cc"],
     deps = [
         ":chrono_interop",
         ":prefix",
@@ -171,7 +178,8 @@ cc_test(
 cc_library(
     name = "chrono_policy_validation",
     testonly = True,
-    hdrs = ["chrono_policy_validation.hh"],
+    hdrs = ["code/au/chrono_policy_validation.hh"],
+    includes = ["code"],
     deps = [
         ":dimension",
         ":quantity",
@@ -184,7 +192,7 @@ cc_library(
 cc_test(
     name = "chrono_policy_validation_test",
     size = "small",
-    srcs = ["chrono_policy_validation_test.cc"],
+    srcs = ["code/au/chrono_policy_validation_test.cc"],
     deps = [
         ":chrono_policy_validation",
         ":prefix",
@@ -195,7 +203,8 @@ cc_test(
 
 cc_library(
     name = "constant",
-    hdrs = ["constant.hh"],
+    hdrs = ["code/au/constant.hh"],
+    includes = ["code"],
     deps = [
         ":quantity",
         ":unit_of_measure",
@@ -206,7 +215,7 @@ cc_library(
 cc_test(
     name = "constant_test",
     size = "small",
-    srcs = ["constant_test.cc"],
+    srcs = ["code/au/constant_test.cc"],
     deps = [
         ":chrono_interop",
         ":constant",
@@ -218,7 +227,8 @@ cc_test(
 
 cc_library(
     name = "conversion_policy",
-    hdrs = ["conversion_policy.hh"],
+    hdrs = ["code/au/conversion_policy.hh"],
+    includes = ["code"],
     deps = [
         ":magnitude",
         ":stdx",
@@ -229,7 +239,7 @@ cc_library(
 cc_test(
     name = "conversion_policy_test",
     size = "small",
-    srcs = ["conversion_policy_test.cc"],
+    srcs = ["code/au/conversion_policy_test.cc"],
     deps = [
         ":conversion_policy",
         ":unit_of_measure",
@@ -239,7 +249,8 @@ cc_test(
 
 cc_library(
     name = "dimension",
-    hdrs = ["dimension.hh"],
+    hdrs = ["code/au/dimension.hh"],
+    includes = ["code"],
     deps = [
         ":packs",
         ":power_aliases",
@@ -249,7 +260,7 @@ cc_library(
 cc_test(
     name = "dimension_test",
     size = "small",
-    srcs = ["dimension_test.cc"],
+    srcs = ["code/au/dimension_test.cc"],
     deps = [
         ":dimension",
         ":testing",
@@ -260,7 +271,8 @@ cc_test(
 
 cc_library(
     name = "magnitude",
-    hdrs = ["magnitude.hh"],
+    hdrs = ["code/au/magnitude.hh"],
+    includes = ["code"],
     deps = [
         ":packs",
         ":power_aliases",
@@ -273,7 +285,7 @@ cc_library(
 cc_test(
     name = "magnitude_test",
     size = "small",
-    srcs = ["magnitude_test.cc"],
+    srcs = ["code/au/magnitude_test.cc"],
     deps = [
         ":magnitude",
         ":testing",
@@ -283,7 +295,8 @@ cc_test(
 
 cc_library(
     name = "math",
-    hdrs = ["math.hh"],
+    hdrs = ["code/au/math.hh"],
+    includes = ["code"],
     deps = [
         ":constant",
         ":quantity",
@@ -295,7 +308,7 @@ cc_library(
 cc_test(
     name = "math_test",
     size = "small",
-    srcs = ["math_test.cc"],
+    srcs = ["code/au/math_test.cc"],
     deps = [
         ":math",
         ":testing",
@@ -306,7 +319,7 @@ cc_test(
 cc_test(
     name = "no_wconversion_test",
     size = "small",
-    srcs = ["no_wconversion_test.cc"],
+    srcs = ["code/au/no_wconversion_test.cc"],
     deps = [
         ":quantity",
         ":testing",
@@ -317,13 +330,14 @@ cc_test(
 
 cc_library(
     name = "operators",
-    hdrs = ["operators.hh"],
+    hdrs = ["code/au/operators.hh"],
+    includes = ["code"],
 )
 
 cc_test(
     name = "operators_test",
     size = "small",
-    srcs = ["operators_test.cc"],
+    srcs = ["code/au/operators_test.cc"],
     deps = [
         ":operators",
         ":testing",
@@ -333,7 +347,8 @@ cc_test(
 
 cc_library(
     name = "packs",
-    hdrs = ["packs.hh"],
+    hdrs = ["code/au/packs.hh"],
+    includes = ["code"],
     deps = [
         ":stdx",
         ":utility",
@@ -343,7 +358,7 @@ cc_library(
 cc_test(
     name = "packs_test",
     size = "small",
-    srcs = ["packs_test.cc"],
+    srcs = ["code/au/packs_test.cc"],
     deps = [
         ":packs",
         "@com_google_googletest//:gtest_main",
@@ -352,13 +367,14 @@ cc_test(
 
 cc_library(
     name = "power_aliases",
-    hdrs = ["power_aliases.hh"],
+    hdrs = ["code/au/power_aliases.hh"],
+    includes = ["code"],
 )
 
 cc_test(
     name = "power_aliases_test",
     size = "small",
-    srcs = ["power_aliases_test.cc"],
+    srcs = ["code/au/power_aliases_test.cc"],
     deps = [
         ":packs",
         ":power_aliases",
@@ -368,7 +384,8 @@ cc_test(
 
 cc_library(
     name = "prefix",
-    hdrs = ["prefix.hh"],
+    hdrs = ["code/au/prefix.hh"],
+    includes = ["code"],
     deps = [
         ":quantity",
         ":quantity_point",
@@ -380,7 +397,7 @@ cc_library(
 cc_test(
     name = "prefix_test",
     size = "small",
-    srcs = ["prefix_test.cc"],
+    srcs = ["code/au/prefix_test.cc"],
     deps = [
         ":prefix",
         ":testing",
@@ -390,7 +407,8 @@ cc_test(
 
 cc_library(
     name = "quantity",
-    hdrs = ["quantity.hh"],
+    hdrs = ["code/au/quantity.hh"],
+    includes = ["code"],
     deps = [
         ":apply_magnitude",
         ":conversion_policy",
@@ -405,8 +423,8 @@ cc_test(
     name = "quantity_test",
     size = "small",
     srcs = [
-        "quantity_chrono_policy_correspondence_test.cc",
-        "quantity_test.cc",
+        "code/au/quantity_chrono_policy_correspondence_test.cc",
+        "code/au/quantity_test.cc",
     ],
     deps = [
         ":chrono_policy_validation",
@@ -419,7 +437,8 @@ cc_test(
 
 cc_library(
     name = "quantity_point",
-    hdrs = ["quantity_point.hh"],
+    hdrs = ["code/au/quantity_point.hh"],
+    includes = ["code"],
     deps = [
         ":quantity",
         ":stdx",
@@ -430,7 +449,7 @@ cc_library(
 cc_test(
     name = "quantity_point_test",
     size = "small",
-    srcs = ["quantity_point_test.cc"],
+    srcs = ["code/au/quantity_point_test.cc"],
     deps = [
         ":prefix",
         ":quantity_point",
@@ -441,14 +460,15 @@ cc_test(
 
 cc_library(
     name = "rep",
-    hdrs = ["rep.hh"],
+    hdrs = ["code/au/rep.hh"],
+    includes = ["code"],
     deps = [":stdx"],
 )
 
 cc_test(
     name = "rep_test",
     size = "small",
-    srcs = ["rep_test.cc"],
+    srcs = ["code/au/rep_test.cc"],
     deps = [
         ":chrono_interop",
         ":constant",
@@ -466,19 +486,20 @@ cc_test(
 cc_library(
     name = "stdx",
     srcs = glob([
-        "stdx/*.cc",
-        "stdx/experimental/*.cc",
+        "code/au/stdx/*.cc",
+        "code/au/stdx/experimental/*.cc",
     ]),
     hdrs = glob([
-        "stdx/*.hh",
-        "stdx/experimental/*.hh",
+        "code/au/stdx/*.hh",
+        "code/au/stdx/experimental/*.hh",
     ]),
+    includes = ["code"],
 )
 
 cc_test(
     name = "stdx_test",
     size = "small",
-    srcs = glob(["stdx/test/*.cc"]),
+    srcs = glob(["code/au/stdx/test/*.cc"]),
     deps = [
         ":stdx",
         "@com_google_googletest//:gtest_main",
@@ -487,7 +508,8 @@ cc_test(
 
 cc_library(
     name = "unit_of_measure",
-    hdrs = ["unit_of_measure.hh"],
+    hdrs = ["code/au/unit_of_measure.hh"],
+    includes = ["code"],
     deps = [
         ":dimension",
         ":magnitude",
@@ -501,7 +523,7 @@ cc_library(
 cc_test(
     name = "unit_of_measure_test",
     size = "small",
-    srcs = ["unit_of_measure_test.cc"],
+    srcs = ["code/au/unit_of_measure_test.cc"],
     deps = [
         ":prefix",
         ":testing",
@@ -513,14 +535,15 @@ cc_test(
 
 cc_library(
     name = "unit_symbol",
-    hdrs = ["unit_symbol.hh"],
+    hdrs = ["code/au/unit_symbol.hh"],
+    includes = ["code"],
     deps = [":wrapper_operations"],
 )
 
 cc_test(
     name = "unit_symbol_test",
     size = "small",
-    srcs = ["unit_symbol_test.cc"],
+    srcs = ["code/au/unit_symbol_test.cc"],
     deps = [
         ":testing",
         ":unit_symbol",
@@ -531,14 +554,15 @@ cc_test(
 
 cc_library(
     name = "utility",
-    hdrs = glob(["utility/*.hh"]),
+    hdrs = glob(["code/au/utility/*.hh"]),
+    includes = ["code"],
     deps = [":stdx"],
 )
 
 cc_test(
     name = "utility_test",
     size = "small",
-    srcs = glob(["utility/test/*.cc"]),
+    srcs = glob(["code/au/utility/test/*.cc"]),
     deps = [
         ":utility",
         "@com_google_googletest//:gtest_main",
@@ -547,7 +571,8 @@ cc_test(
 
 cc_library(
     name = "wrapper_operations",
-    hdrs = ["wrapper_operations.hh"],
+    hdrs = ["code/au/wrapper_operations.hh"],
+    includes = ["code"],
     deps = [
         ":quantity",
         ":stdx",
@@ -557,7 +582,7 @@ cc_library(
 cc_test(
     name = "wrapper_operations_test",
     size = "small",
-    srcs = ["wrapper_operations_test.cc"],
+    srcs = ["code/au/wrapper_operations_test.cc"],
     deps = [
         ":testing",
         ":units",
@@ -568,13 +593,14 @@ cc_test(
 
 cc_library(
     name = "zero",
-    hdrs = ["zero.hh"],
+    hdrs = ["code/au/zero.hh"],
+    includes = ["code"],
 )
 
 cc_test(
     name = "zero_test",
     size = "small",
-    srcs = ["zero_test.cc"],
+    srcs = ["code/au/zero_test.cc"],
     deps = [
         ":zero",
         "@com_google_googletest//:gtest_main",
@@ -586,7 +612,7 @@ cc_test(
 
 filegroup(
     name = "headers",
-    srcs = glob(["**/*.hh"]),
+    srcs = glob(["code/au/**/*.hh"]),
     visibility = ["//:__pkg__"],
 )
 
diff --git a/au/CMakeLists.txt b/au/CMakeLists.txt
index 35492412..a3656289 100644
--- a/au/CMakeLists.txt
+++ b/au/CMakeLists.txt
@@ -12,494 +12,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-include("${PROJECT_SOURCE_DIR}/cmake/HeaderOnlyLibrary.cmake")
-
-#
-# Publicly exported targets
-#
-
-header_only_library(
-  NAME au
-  HEADERS
-    au.hh
-  DEPS
-    chrono_interop
-    constant
-    math
-  GTEST_SRCS
-    au_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME chrono_interop
-  HEADERS
-    chrono_interop.hh
-  DEPS
-    quantity
-    units
-  GTEST_SRCS
-    chrono_interop_test.cc
-  GTEST_EXTRA_DEPS
-    prefix
-    testing
-)
-
-header_only_library(
-  NAME constant
-  HEADERS
-    constant.hh
-  DEPS
-    quantity
-    unit_of_measure
-    wrapper_operations
-  GTEST_SRCS
-    constant_test.cc
-  GTEST_EXTRA_DEPS
-    chrono_interop
-    testing
-    units
-)
-
-header_only_library(
-  NAME io
-  HEADERS
-    io.hh
-  DEPS
-    quantity
-    quantity_point
-    zero
-  GTEST_SRCS
-    io_test.cc
-  GTEST_EXTRA_DEPS
-    prefix
-)
-
-header_only_library(
-  NAME math
-  HEADERS
-    math.hh
-  DEPS
-    constant
-    quantity
-    quantity_point
-    units
-  GTEST_SRCS
-    math_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME prefix
-  HEADERS
-    prefix.hh
-  DEPS
-    quantity
-    quantity_point
-    unit_of_measure
-    unit_symbol
-  GTEST_SRCS
-    prefix_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME quantity
-  HEADERS
-    quantity.hh
-  DEPS
-    apply_magnitude
-    conversion_policy
-    operators
-    rep
-    unit_of_measure
-    zero
-  GTEST_SRCS
-    quantity_chrono_policy_correspondence_test.cc
-    quantity_test.cc
-  GTEST_EXTRA_DEPS
-    chrono_policy_validation
-    prefix
-    testing
-)
-
-header_only_library(
-  NAME quantity_point
-  HEADERS
-    quantity_point.hh
-  DEPS
-    quantity
-    stdx
-    utility
-  GTEST_SRCS
-    quantity_point_test.cc
-  GTEST_EXTRA_DEPS
-    prefix
-    testing
-)
-
-header_only_library(
-  NAME testing
-  HEADERS
-    testing.hh
-  DEPS
-    io
-    stdx
-    unit_of_measure
-    GTest::gmock
-  GTEST_SRCS
-    testing_test.cc
-)
-
-header_only_library(
-  NAME units
-  HEADERS
-    units/amperes.hh
-    units/bars.hh
-    units/becquerel.hh
-    units/bits.hh
-    units/bytes.hh
-    units/candelas.hh
-    units/celsius.hh
-    units/coulombs.hh
-    units/days.hh
-    units/degrees.hh
-    units/fahrenheit.hh
-    units/farads.hh
-    units/fathoms.hh
-    units/feet.hh
-    units/furlongs.hh
-    units/grams.hh
-    units/grays.hh
-    units/henries.hh
-    units/hertz.hh
-    units/hours.hh
-    units/inches.hh
-    units/joules.hh
-    units/katals.hh
-    units/kelvins.hh
-    units/knots.hh
-    units/liters.hh
-    units/lumens.hh
-    units/lux.hh
-    units/meters.hh
-    units/miles.hh
-    units/minutes.hh
-    units/moles.hh
-    units/nautical_miles.hh
-    units/newtons.hh
-    units/ohms.hh
-    units/pascals.hh
-    units/percent.hh
-    units/pounds_force.hh
-    units/pounds_mass.hh
-    units/radians.hh
-    units/revolutions.hh
-    units/seconds.hh
-    units/siemens.hh
-    units/slugs.hh
-    units/standard_gravity.hh
-    units/steradians.hh
-    units/tesla.hh
-    units/unos.hh
-    units/volts.hh
-    units/watts.hh
-    units/webers.hh
-    units/yards.hh
-  DEPS
-    prefix
-    quantity
-    quantity_point
-    unit_of_measure
-    unit_symbol
-  GTEST_SRCS
-    units/test/amperes_test.cc
-    units/test/bars_test.cc
-    units/test/becquerel_test.cc
-    units/test/bits_test.cc
-    units/test/bytes_test.cc
-    units/test/candelas_test.cc
-    units/test/celsius_test.cc
-    units/test/coulombs_test.cc
-    units/test/days_test.cc
-    units/test/degrees_test.cc
-    units/test/fahrenheit_test.cc
-    units/test/farads_test.cc
-    units/test/fathoms_test.cc
-    units/test/feet_test.cc
-    units/test/furlongs_test.cc
-    units/test/grams_test.cc
-    units/test/grays_test.cc
-    units/test/henries_test.cc
-    units/test/hertz_test.cc
-    units/test/hours_test.cc
-    units/test/inches_test.cc
-    units/test/joules_test.cc
-    units/test/katals_test.cc
-    units/test/kelvins_test.cc
-    units/test/knots_test.cc
-    units/test/liters_test.cc
-    units/test/lumens_test.cc
-    units/test/lux_test.cc
-    units/test/meters_test.cc
-    units/test/miles_test.cc
-    units/test/minutes_test.cc
-    units/test/moles_test.cc
-    units/test/nautical_miles_test.cc
-    units/test/newtons_test.cc
-    units/test/ohms_test.cc
-    units/test/pascals_test.cc
-    units/test/percent_test.cc
-    units/test/pounds_force_test.cc
-    units/test/pounds_mass_test.cc
-    units/test/radians_test.cc
-    units/test/revolutions_test.cc
-    units/test/seconds_test.cc
-    units/test/siemens_test.cc
-    units/test/slugs_test.cc
-    units/test/standard_gravity_test.cc
-    units/test/steradians_test.cc
-    units/test/tesla_test.cc
-    units/test/unos_test.cc
-    units/test/volts_test.cc
-    units/test/watts_test.cc
-    units/test/webers_test.cc
-    units/test/yards_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME unit_symbol
-  HEADERS
-    unit_symbol.hh
-  DEPS
-    wrapper_operations
-  GTEST_SRCS
-    unit_symbol_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-    units
-)
-
-#
-# Private implementation detail targets
-#
-
-header_only_library(
-  NAME apply_magnitude
-  INTERNAL_ONLY
-  HEADERS
-    apply_magnitude.hh
-  DEPS
-    apply_rational_magnitude_to_integral
-  GTEST_SRCS
-    apply_magnitude_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME apply_rational_magnitude_to_integral
-  INTERNAL_ONLY
-  HEADERS
-    apply_rational_magnitude_to_integral.hh
-  DEPS
-    magnitude
-  GTEST_SRCS
-    apply_rational_magnitude_to_integral_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME chrono_policy_validation
-  INTERNAL_ONLY
-  HEADERS
-    chrono_policy_validation.hh
-  DEPS
-    dimension
-    quantity
-    stdx
-    unit_of_measure
-    GTest::gtest
-  GTEST_SRCS
-    chrono_policy_validation_test.cc
-  GTEST_EXTRA_DEPS
-    prefix
-    testing
-)
-
-
-header_only_library(
-  NAME conversion_policy
-  INTERNAL_ONLY
-  HEADERS
-    conversion_policy.hh
-  DEPS
-    magnitude
-    stdx
-    unit_of_measure
-  GTEST_SRCS
-    conversion_policy_test.cc
-)
-
-header_only_library(
-  NAME dimension
-  INTERNAL_ONLY
-  HEADERS
-    dimension.hh
-  DEPS
-    packs
-    power_aliases
-  GTEST_SRCS
-    dimension_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-    units
-)
-
-header_only_library(
-  NAME magnitude
-  INTERNAL_ONLY
-  HEADERS
-    magnitude.hh
-  DEPS
-    packs
-    power_aliases
-    stdx
-    utility
-    zero
-  GTEST_SRCS
-    magnitude_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME operators
-  INTERNAL_ONLY
-  HEADERS
-    operators.hh
-  GTEST_SRCS
-    operators_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-)
-
-header_only_library(
-  NAME packs
-  INTERNAL_ONLY
-  HEADERS
-    packs.hh
-  DEPS
-    stdx
-    utility
-  GTEST_SRCS
-    packs_test.cc
-)
-
-header_only_library(
-  NAME power_aliases
-  INTERNAL_ONLY
-  HEADERS
-    power_aliases.hh
-  GTEST_SRCS
-    power_aliases_test.cc
-  GTEST_EXTRA_DEPS
-    packs
-)
-
-header_only_library(
-  NAME rep
-  INTERNAL_ONLY
-  HEADERS
-    rep.hh
-  DEPS
-    stdx
-  GTEST_SRCS
-    rep_test.cc
-  GTEST_EXTRA_DEPS
-    chrono_interop
-    constant
-    magnitude
-    prefix
-    quantity
-    quantity_point
-    unit_symbol
-    units
-)
-
-header_only_library(
-  NAME stdx
-  INTERNAL_ONLY
-  HEADERS
-    stdx/experimental/is_detected.hh
-    stdx/functional.hh
-    stdx/type_traits.hh
-    stdx/utility.hh
-  GTEST_SRCS
-    stdx/test/utility_test.cc
-)
-
-header_only_library(
-  NAME unit_of_measure
-  INTERNAL_ONLY
-  HEADERS
-    unit_of_measure.hh
-  DEPS
-    dimension
-    magnitude
-    power_aliases
-    stdx
-    utility
-    zero
-  GTEST_SRCS
-    unit_of_measure_test.cc
-  GTEST_EXTRA_DEPS
-    prefix
-    testing
-    units
-)
-
-header_only_library(
-  NAME utility
-  INTERNAL_ONLY
-  HEADERS
-    utility/factoring.hh
-    utility/string_constant.hh
-    utility/type_traits.hh
-  DEPS
-    stdx
-  GTEST_SRCS
-    utility/test/factoring_test.cc
-    utility/test/string_constant_test.cc
-    utility/test/type_traits_test.cc
-)
-
-header_only_library(
-  NAME wrapper_operations
-  INTERNAL_ONLY
-  HEADERS
-    wrapper_operations.hh
-  DEPS
-    quantity
-    stdx
-  GTEST_SRCS
-    wrapper_operations_test.cc
-  GTEST_EXTRA_DEPS
-    testing
-    units
-)
-
-header_only_library(
-  NAME zero
-  INTERNAL_ONLY
-  HEADERS
-    zero.hh
-  GTEST_SRCS
-    zero_test.cc
-)
+add_subdirectory(code)
diff --git a/cmake/project_symlinks/CMakeLists.txt b/au/code/CMakeLists.txt
similarity index 100%
rename from cmake/project_symlinks/CMakeLists.txt
rename to au/code/CMakeLists.txt
diff --git a/au/code/au/CMakeLists.txt b/au/code/au/CMakeLists.txt
new file mode 100644
index 00000000..35492412
--- /dev/null
+++ b/au/code/au/CMakeLists.txt
@@ -0,0 +1,505 @@
+# Copyright 2024 Aurora Operations, Inc.
+#
+# 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
+#
+#     http://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.
+
+include("${PROJECT_SOURCE_DIR}/cmake/HeaderOnlyLibrary.cmake")
+
+#
+# Publicly exported targets
+#
+
+header_only_library(
+  NAME au
+  HEADERS
+    au.hh
+  DEPS
+    chrono_interop
+    constant
+    math
+  GTEST_SRCS
+    au_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME chrono_interop
+  HEADERS
+    chrono_interop.hh
+  DEPS
+    quantity
+    units
+  GTEST_SRCS
+    chrono_interop_test.cc
+  GTEST_EXTRA_DEPS
+    prefix
+    testing
+)
+
+header_only_library(
+  NAME constant
+  HEADERS
+    constant.hh
+  DEPS
+    quantity
+    unit_of_measure
+    wrapper_operations
+  GTEST_SRCS
+    constant_test.cc
+  GTEST_EXTRA_DEPS
+    chrono_interop
+    testing
+    units
+)
+
+header_only_library(
+  NAME io
+  HEADERS
+    io.hh
+  DEPS
+    quantity
+    quantity_point
+    zero
+  GTEST_SRCS
+    io_test.cc
+  GTEST_EXTRA_DEPS
+    prefix
+)
+
+header_only_library(
+  NAME math
+  HEADERS
+    math.hh
+  DEPS
+    constant
+    quantity
+    quantity_point
+    units
+  GTEST_SRCS
+    math_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME prefix
+  HEADERS
+    prefix.hh
+  DEPS
+    quantity
+    quantity_point
+    unit_of_measure
+    unit_symbol
+  GTEST_SRCS
+    prefix_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME quantity
+  HEADERS
+    quantity.hh
+  DEPS
+    apply_magnitude
+    conversion_policy
+    operators
+    rep
+    unit_of_measure
+    zero
+  GTEST_SRCS
+    quantity_chrono_policy_correspondence_test.cc
+    quantity_test.cc
+  GTEST_EXTRA_DEPS
+    chrono_policy_validation
+    prefix
+    testing
+)
+
+header_only_library(
+  NAME quantity_point
+  HEADERS
+    quantity_point.hh
+  DEPS
+    quantity
+    stdx
+    utility
+  GTEST_SRCS
+    quantity_point_test.cc
+  GTEST_EXTRA_DEPS
+    prefix
+    testing
+)
+
+header_only_library(
+  NAME testing
+  HEADERS
+    testing.hh
+  DEPS
+    io
+    stdx
+    unit_of_measure
+    GTest::gmock
+  GTEST_SRCS
+    testing_test.cc
+)
+
+header_only_library(
+  NAME units
+  HEADERS
+    units/amperes.hh
+    units/bars.hh
+    units/becquerel.hh
+    units/bits.hh
+    units/bytes.hh
+    units/candelas.hh
+    units/celsius.hh
+    units/coulombs.hh
+    units/days.hh
+    units/degrees.hh
+    units/fahrenheit.hh
+    units/farads.hh
+    units/fathoms.hh
+    units/feet.hh
+    units/furlongs.hh
+    units/grams.hh
+    units/grays.hh
+    units/henries.hh
+    units/hertz.hh
+    units/hours.hh
+    units/inches.hh
+    units/joules.hh
+    units/katals.hh
+    units/kelvins.hh
+    units/knots.hh
+    units/liters.hh
+    units/lumens.hh
+    units/lux.hh
+    units/meters.hh
+    units/miles.hh
+    units/minutes.hh
+    units/moles.hh
+    units/nautical_miles.hh
+    units/newtons.hh
+    units/ohms.hh
+    units/pascals.hh
+    units/percent.hh
+    units/pounds_force.hh
+    units/pounds_mass.hh
+    units/radians.hh
+    units/revolutions.hh
+    units/seconds.hh
+    units/siemens.hh
+    units/slugs.hh
+    units/standard_gravity.hh
+    units/steradians.hh
+    units/tesla.hh
+    units/unos.hh
+    units/volts.hh
+    units/watts.hh
+    units/webers.hh
+    units/yards.hh
+  DEPS
+    prefix
+    quantity
+    quantity_point
+    unit_of_measure
+    unit_symbol
+  GTEST_SRCS
+    units/test/amperes_test.cc
+    units/test/bars_test.cc
+    units/test/becquerel_test.cc
+    units/test/bits_test.cc
+    units/test/bytes_test.cc
+    units/test/candelas_test.cc
+    units/test/celsius_test.cc
+    units/test/coulombs_test.cc
+    units/test/days_test.cc
+    units/test/degrees_test.cc
+    units/test/fahrenheit_test.cc
+    units/test/farads_test.cc
+    units/test/fathoms_test.cc
+    units/test/feet_test.cc
+    units/test/furlongs_test.cc
+    units/test/grams_test.cc
+    units/test/grays_test.cc
+    units/test/henries_test.cc
+    units/test/hertz_test.cc
+    units/test/hours_test.cc
+    units/test/inches_test.cc
+    units/test/joules_test.cc
+    units/test/katals_test.cc
+    units/test/kelvins_test.cc
+    units/test/knots_test.cc
+    units/test/liters_test.cc
+    units/test/lumens_test.cc
+    units/test/lux_test.cc
+    units/test/meters_test.cc
+    units/test/miles_test.cc
+    units/test/minutes_test.cc
+    units/test/moles_test.cc
+    units/test/nautical_miles_test.cc
+    units/test/newtons_test.cc
+    units/test/ohms_test.cc
+    units/test/pascals_test.cc
+    units/test/percent_test.cc
+    units/test/pounds_force_test.cc
+    units/test/pounds_mass_test.cc
+    units/test/radians_test.cc
+    units/test/revolutions_test.cc
+    units/test/seconds_test.cc
+    units/test/siemens_test.cc
+    units/test/slugs_test.cc
+    units/test/standard_gravity_test.cc
+    units/test/steradians_test.cc
+    units/test/tesla_test.cc
+    units/test/unos_test.cc
+    units/test/volts_test.cc
+    units/test/watts_test.cc
+    units/test/webers_test.cc
+    units/test/yards_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME unit_symbol
+  HEADERS
+    unit_symbol.hh
+  DEPS
+    wrapper_operations
+  GTEST_SRCS
+    unit_symbol_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+    units
+)
+
+#
+# Private implementation detail targets
+#
+
+header_only_library(
+  NAME apply_magnitude
+  INTERNAL_ONLY
+  HEADERS
+    apply_magnitude.hh
+  DEPS
+    apply_rational_magnitude_to_integral
+  GTEST_SRCS
+    apply_magnitude_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME apply_rational_magnitude_to_integral
+  INTERNAL_ONLY
+  HEADERS
+    apply_rational_magnitude_to_integral.hh
+  DEPS
+    magnitude
+  GTEST_SRCS
+    apply_rational_magnitude_to_integral_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME chrono_policy_validation
+  INTERNAL_ONLY
+  HEADERS
+    chrono_policy_validation.hh
+  DEPS
+    dimension
+    quantity
+    stdx
+    unit_of_measure
+    GTest::gtest
+  GTEST_SRCS
+    chrono_policy_validation_test.cc
+  GTEST_EXTRA_DEPS
+    prefix
+    testing
+)
+
+
+header_only_library(
+  NAME conversion_policy
+  INTERNAL_ONLY
+  HEADERS
+    conversion_policy.hh
+  DEPS
+    magnitude
+    stdx
+    unit_of_measure
+  GTEST_SRCS
+    conversion_policy_test.cc
+)
+
+header_only_library(
+  NAME dimension
+  INTERNAL_ONLY
+  HEADERS
+    dimension.hh
+  DEPS
+    packs
+    power_aliases
+  GTEST_SRCS
+    dimension_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+    units
+)
+
+header_only_library(
+  NAME magnitude
+  INTERNAL_ONLY
+  HEADERS
+    magnitude.hh
+  DEPS
+    packs
+    power_aliases
+    stdx
+    utility
+    zero
+  GTEST_SRCS
+    magnitude_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME operators
+  INTERNAL_ONLY
+  HEADERS
+    operators.hh
+  GTEST_SRCS
+    operators_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+)
+
+header_only_library(
+  NAME packs
+  INTERNAL_ONLY
+  HEADERS
+    packs.hh
+  DEPS
+    stdx
+    utility
+  GTEST_SRCS
+    packs_test.cc
+)
+
+header_only_library(
+  NAME power_aliases
+  INTERNAL_ONLY
+  HEADERS
+    power_aliases.hh
+  GTEST_SRCS
+    power_aliases_test.cc
+  GTEST_EXTRA_DEPS
+    packs
+)
+
+header_only_library(
+  NAME rep
+  INTERNAL_ONLY
+  HEADERS
+    rep.hh
+  DEPS
+    stdx
+  GTEST_SRCS
+    rep_test.cc
+  GTEST_EXTRA_DEPS
+    chrono_interop
+    constant
+    magnitude
+    prefix
+    quantity
+    quantity_point
+    unit_symbol
+    units
+)
+
+header_only_library(
+  NAME stdx
+  INTERNAL_ONLY
+  HEADERS
+    stdx/experimental/is_detected.hh
+    stdx/functional.hh
+    stdx/type_traits.hh
+    stdx/utility.hh
+  GTEST_SRCS
+    stdx/test/utility_test.cc
+)
+
+header_only_library(
+  NAME unit_of_measure
+  INTERNAL_ONLY
+  HEADERS
+    unit_of_measure.hh
+  DEPS
+    dimension
+    magnitude
+    power_aliases
+    stdx
+    utility
+    zero
+  GTEST_SRCS
+    unit_of_measure_test.cc
+  GTEST_EXTRA_DEPS
+    prefix
+    testing
+    units
+)
+
+header_only_library(
+  NAME utility
+  INTERNAL_ONLY
+  HEADERS
+    utility/factoring.hh
+    utility/string_constant.hh
+    utility/type_traits.hh
+  DEPS
+    stdx
+  GTEST_SRCS
+    utility/test/factoring_test.cc
+    utility/test/string_constant_test.cc
+    utility/test/type_traits_test.cc
+)
+
+header_only_library(
+  NAME wrapper_operations
+  INTERNAL_ONLY
+  HEADERS
+    wrapper_operations.hh
+  DEPS
+    quantity
+    stdx
+  GTEST_SRCS
+    wrapper_operations_test.cc
+  GTEST_EXTRA_DEPS
+    testing
+    units
+)
+
+header_only_library(
+  NAME zero
+  INTERNAL_ONLY
+  HEADERS
+    zero.hh
+  GTEST_SRCS
+    zero_test.cc
+)
diff --git a/au/apply_magnitude.hh b/au/code/au/apply_magnitude.hh
similarity index 100%
rename from au/apply_magnitude.hh
rename to au/code/au/apply_magnitude.hh
diff --git a/au/apply_magnitude_test.cc b/au/code/au/apply_magnitude_test.cc
similarity index 100%
rename from au/apply_magnitude_test.cc
rename to au/code/au/apply_magnitude_test.cc
diff --git a/au/apply_rational_magnitude_to_integral.hh b/au/code/au/apply_rational_magnitude_to_integral.hh
similarity index 100%
rename from au/apply_rational_magnitude_to_integral.hh
rename to au/code/au/apply_rational_magnitude_to_integral.hh
diff --git a/au/apply_rational_magnitude_to_integral_test.cc b/au/code/au/apply_rational_magnitude_to_integral_test.cc
similarity index 100%
rename from au/apply_rational_magnitude_to_integral_test.cc
rename to au/code/au/apply_rational_magnitude_to_integral_test.cc
diff --git a/au/au.hh b/au/code/au/au.hh
similarity index 100%
rename from au/au.hh
rename to au/code/au/au.hh
diff --git a/au/au_test.cc b/au/code/au/au_test.cc
similarity index 100%
rename from au/au_test.cc
rename to au/code/au/au_test.cc
diff --git a/au/chrono_interop.hh b/au/code/au/chrono_interop.hh
similarity index 100%
rename from au/chrono_interop.hh
rename to au/code/au/chrono_interop.hh
diff --git a/au/chrono_interop_test.cc b/au/code/au/chrono_interop_test.cc
similarity index 100%
rename from au/chrono_interop_test.cc
rename to au/code/au/chrono_interop_test.cc
diff --git a/au/chrono_policy_validation.hh b/au/code/au/chrono_policy_validation.hh
similarity index 100%
rename from au/chrono_policy_validation.hh
rename to au/code/au/chrono_policy_validation.hh
diff --git a/au/chrono_policy_validation_test.cc b/au/code/au/chrono_policy_validation_test.cc
similarity index 100%
rename from au/chrono_policy_validation_test.cc
rename to au/code/au/chrono_policy_validation_test.cc
diff --git a/au/constant.hh b/au/code/au/constant.hh
similarity index 100%
rename from au/constant.hh
rename to au/code/au/constant.hh
diff --git a/au/constant_test.cc b/au/code/au/constant_test.cc
similarity index 100%
rename from au/constant_test.cc
rename to au/code/au/constant_test.cc
diff --git a/au/conversion_policy.hh b/au/code/au/conversion_policy.hh
similarity index 100%
rename from au/conversion_policy.hh
rename to au/code/au/conversion_policy.hh
diff --git a/au/conversion_policy_test.cc b/au/code/au/conversion_policy_test.cc
similarity index 100%
rename from au/conversion_policy_test.cc
rename to au/code/au/conversion_policy_test.cc
diff --git a/au/dimension.hh b/au/code/au/dimension.hh
similarity index 100%
rename from au/dimension.hh
rename to au/code/au/dimension.hh
diff --git a/au/dimension_test.cc b/au/code/au/dimension_test.cc
similarity index 100%
rename from au/dimension_test.cc
rename to au/code/au/dimension_test.cc
diff --git a/au/io.hh b/au/code/au/io.hh
similarity index 100%
rename from au/io.hh
rename to au/code/au/io.hh
diff --git a/au/io_test.cc b/au/code/au/io_test.cc
similarity index 100%
rename from au/io_test.cc
rename to au/code/au/io_test.cc
diff --git a/au/magnitude.hh b/au/code/au/magnitude.hh
similarity index 100%
rename from au/magnitude.hh
rename to au/code/au/magnitude.hh
diff --git a/au/magnitude_test.cc b/au/code/au/magnitude_test.cc
similarity index 100%
rename from au/magnitude_test.cc
rename to au/code/au/magnitude_test.cc
diff --git a/au/math.hh b/au/code/au/math.hh
similarity index 100%
rename from au/math.hh
rename to au/code/au/math.hh
diff --git a/au/math_test.cc b/au/code/au/math_test.cc
similarity index 100%
rename from au/math_test.cc
rename to au/code/au/math_test.cc
diff --git a/au/no_wconversion_test.cc b/au/code/au/no_wconversion_test.cc
similarity index 100%
rename from au/no_wconversion_test.cc
rename to au/code/au/no_wconversion_test.cc
diff --git a/au/operators.hh b/au/code/au/operators.hh
similarity index 100%
rename from au/operators.hh
rename to au/code/au/operators.hh
diff --git a/au/operators_test.cc b/au/code/au/operators_test.cc
similarity index 100%
rename from au/operators_test.cc
rename to au/code/au/operators_test.cc
diff --git a/au/packs.hh b/au/code/au/packs.hh
similarity index 100%
rename from au/packs.hh
rename to au/code/au/packs.hh
diff --git a/au/packs_test.cc b/au/code/au/packs_test.cc
similarity index 100%
rename from au/packs_test.cc
rename to au/code/au/packs_test.cc
diff --git a/au/power_aliases.hh b/au/code/au/power_aliases.hh
similarity index 100%
rename from au/power_aliases.hh
rename to au/code/au/power_aliases.hh
diff --git a/au/power_aliases_test.cc b/au/code/au/power_aliases_test.cc
similarity index 100%
rename from au/power_aliases_test.cc
rename to au/code/au/power_aliases_test.cc
diff --git a/au/prefix.hh b/au/code/au/prefix.hh
similarity index 100%
rename from au/prefix.hh
rename to au/code/au/prefix.hh
diff --git a/au/prefix_test.cc b/au/code/au/prefix_test.cc
similarity index 100%
rename from au/prefix_test.cc
rename to au/code/au/prefix_test.cc
diff --git a/au/quantity.hh b/au/code/au/quantity.hh
similarity index 100%
rename from au/quantity.hh
rename to au/code/au/quantity.hh
diff --git a/au/quantity_chrono_policy_correspondence_test.cc b/au/code/au/quantity_chrono_policy_correspondence_test.cc
similarity index 100%
rename from au/quantity_chrono_policy_correspondence_test.cc
rename to au/code/au/quantity_chrono_policy_correspondence_test.cc
diff --git a/au/quantity_point.hh b/au/code/au/quantity_point.hh
similarity index 100%
rename from au/quantity_point.hh
rename to au/code/au/quantity_point.hh
diff --git a/au/quantity_point_test.cc b/au/code/au/quantity_point_test.cc
similarity index 100%
rename from au/quantity_point_test.cc
rename to au/code/au/quantity_point_test.cc
diff --git a/au/quantity_test.cc b/au/code/au/quantity_test.cc
similarity index 100%
rename from au/quantity_test.cc
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rename from au/units/test/volts_test.cc
rename to au/code/au/units/test/volts_test.cc
diff --git a/au/units/test/watts_test.cc b/au/code/au/units/test/watts_test.cc
similarity index 100%
rename from au/units/test/watts_test.cc
rename to au/code/au/units/test/watts_test.cc
diff --git a/au/units/test/webers_test.cc b/au/code/au/units/test/webers_test.cc
similarity index 100%
rename from au/units/test/webers_test.cc
rename to au/code/au/units/test/webers_test.cc
diff --git a/au/units/test/yards_test.cc b/au/code/au/units/test/yards_test.cc
similarity index 100%
rename from au/units/test/yards_test.cc
rename to au/code/au/units/test/yards_test.cc
diff --git a/au/units/unos.hh b/au/code/au/units/unos.hh
similarity index 100%
rename from au/units/unos.hh
rename to au/code/au/units/unos.hh
diff --git a/au/units/volts.hh b/au/code/au/units/volts.hh
similarity index 100%
rename from au/units/volts.hh
rename to au/code/au/units/volts.hh
diff --git a/au/units/watts.hh b/au/code/au/units/watts.hh
similarity index 100%
rename from au/units/watts.hh
rename to au/code/au/units/watts.hh
diff --git a/au/units/webers.hh b/au/code/au/units/webers.hh
similarity index 100%
rename from au/units/webers.hh
rename to au/code/au/units/webers.hh
diff --git a/au/units/yards.hh b/au/code/au/units/yards.hh
similarity index 100%
rename from au/units/yards.hh
rename to au/code/au/units/yards.hh
diff --git a/au/utility/factoring.hh b/au/code/au/utility/factoring.hh
similarity index 100%
rename from au/utility/factoring.hh
rename to au/code/au/utility/factoring.hh
diff --git a/au/utility/string_constant.hh b/au/code/au/utility/string_constant.hh
similarity index 100%
rename from au/utility/string_constant.hh
rename to au/code/au/utility/string_constant.hh
diff --git a/au/utility/test/factoring_test.cc b/au/code/au/utility/test/factoring_test.cc
similarity index 100%
rename from au/utility/test/factoring_test.cc
rename to au/code/au/utility/test/factoring_test.cc
diff --git a/au/utility/test/string_constant_test.cc b/au/code/au/utility/test/string_constant_test.cc
similarity index 100%
rename from au/utility/test/string_constant_test.cc
rename to au/code/au/utility/test/string_constant_test.cc
diff --git a/au/utility/test/type_traits_test.cc b/au/code/au/utility/test/type_traits_test.cc
similarity index 100%
rename from au/utility/test/type_traits_test.cc
rename to au/code/au/utility/test/type_traits_test.cc
diff --git a/au/utility/type_traits.hh b/au/code/au/utility/type_traits.hh
similarity index 100%
rename from au/utility/type_traits.hh
rename to au/code/au/utility/type_traits.hh
diff --git a/au/wrapper_operations.hh b/au/code/au/wrapper_operations.hh
similarity index 100%
rename from au/wrapper_operations.hh
rename to au/code/au/wrapper_operations.hh
diff --git a/au/wrapper_operations_test.cc b/au/code/au/wrapper_operations_test.cc
similarity index 100%
rename from au/wrapper_operations_test.cc
rename to au/code/au/wrapper_operations_test.cc
diff --git a/au/zero.hh b/au/code/au/zero.hh
similarity index 100%
rename from au/zero.hh
rename to au/code/au/zero.hh
diff --git a/au/zero_test.cc b/au/code/au/zero_test.cc
similarity index 100%
rename from au/zero_test.cc
rename to au/code/au/zero_test.cc
diff --git a/cmake/HeaderOnlyLibrary.cmake b/cmake/HeaderOnlyLibrary.cmake
index aa1c7da0..28daf006 100644
--- a/cmake/HeaderOnlyLibrary.cmake
+++ b/cmake/HeaderOnlyLibrary.cmake
@@ -45,7 +45,7 @@ function(header_only_library)
     ${ARG_NAME}
     INTERFACE
     FILE_SET HEADERS
-    BASE_DIRS "${PROJECT_SOURCE_DIR}/cmake/project_symlinks"
+    BASE_DIRS "${PROJECT_SOURCE_DIR}/au/code"
     FILES ${ARG_HEADERS}
   )
   if (DEFINED ARG_DEPS)
diff --git a/cmake/project_symlinks/au b/cmake/project_symlinks/au
deleted file mode 120000
index d3a01f93..00000000
--- a/cmake/project_symlinks/au
+++ /dev/null
@@ -1 +0,0 @@
-../../au
\ No newline at end of file
diff --git a/tools/bin/make-single-file b/tools/bin/make-single-file
index ec054ec8..f9a0d78e 100755
--- a/tools/bin/make-single-file
+++ b/tools/bin/make-single-file
@@ -109,7 +109,7 @@ def enumerate_units(args):
     with every existing entry, and then delete `--all-units`.
     """
     if args.all_units:
-        args.units = [f[:-3] for f in os.listdir("au/units/") if f.endswith('.hh')]
+        args.units = [f[:-3] for f in os.listdir("au/code/au/units/") if f.endswith(".hh")]
 
     del args.all_units
     return args
@@ -147,7 +147,7 @@ class SourceFile:
         self.lines = []
 
         in_copyright_header = False
-        with open(filename) as f:
+        with open(os.path.join("au/code", filename)) as f:
             was_last_line_blank = False
             for line in f:
                 if line.startswith("#pragma once"):