diff --git a/.efrocachemap b/.efrocachemap
index ffc0ab54..8453c7ce 100644
--- a/.efrocachemap
+++ b/.efrocachemap
@@ -3933,8 +3933,6 @@
   "assets/build/windows/Win32/vc_redist.x86.exe": "https://files.ballistica.net/cache/ba1/1c/e1/4a1a2eddda2f4aebd5f8b64ab08e",
   "assets/build/windows/Win32/vcruntime140d.dll": "https://files.ballistica.net/cache/ba1/50/8d/bc2600ac9491f1b14d659709451f",
   "ballisticacore-windows/Generic/BallisticaCore.ico": "https://files.ballistica.net/cache/ba1/89/c0/e32c7d2a35dc9aef57cc73b0911a",
-  "ballisticacore-windows/build/Debug_Win32/BallisticaCoreGenericInternal.lib": "https://files.ballistica.net/cache/ba1/bb/ef/cbbb2871d6951c4178c51b9168ee",
-  "ballisticacore-windows/build/Debug_Win32/BallisticaCoreGenericInternal.pdb": "https://files.ballistica.net/cache/ba1/d4/4e/8f19b93f504faf01ab6110076482",
   "build/prefab/full/linux_arm64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/e8/15/872df30172235c867eda63d89589",
   "build/prefab/full/linux_arm64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/74/1d/fc9e33e565475daaac80da5252f0",
   "build/prefab/full/linux_arm64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/78/4f/3c6279192f18688bd84bb6a4411b",
@@ -3970,5 +3968,7 @@
   "build/prefab/lib/mac_x86_64_gui/debug/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/fc/09/e9e374f8ff007abd68731bd3ddb9",
   "build/prefab/lib/mac_x86_64_gui/release/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/21/3f/116ca7d820d2e9722ac2505471f4",
   "build/prefab/lib/mac_x86_64_server/debug/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/86/9f/c6610a0006b255768a74d73ce77b",
-  "build/prefab/lib/mac_x86_64_server/release/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/a1/6e/c4b8e6499dd2404c010eb25fc55e"
+  "build/prefab/lib/mac_x86_64_server/release/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/a1/6e/c4b8e6499dd2404c010eb25fc55e",
+  "build/prefab/lib/windows/Debug_Win32/BallisticaCoreGenericInternal.lib": "https://files.ballistica.net/cache/ba1/f2/05/7ce635c1c407a4182b75b316c36e",
+  "build/prefab/lib/windows/Debug_Win32/BallisticaCoreGenericInternal.pdb": "https://files.ballistica.net/cache/ba1/06/63/ee6a0047fdcc7eac67ad99622ecc"
 }
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 631444f3..b54ae17c 100644
--- a/Makefile
+++ b/Makefile
@@ -486,29 +486,29 @@ build/prefab/full/windows_x86_server/release/dist/BallisticaCoreHeadless.exe: .e
 
 # Windows visual-studio-compiled debug
 
-ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.lib: .efrocachemap
+build/prefab/lib/windows/Debug_%/BallisticaCoreGenericInternal.lib: .efrocachemap
 	@tools/pcommand efrocache_get $@
 
-ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.pdb: .efrocachemap
+build/prefab/lib/windows/Debug_%/BallisticaCoreGenericInternal.pdb: .efrocachemap
 	@tools/pcommand efrocache_get $@
 
 ballisticacore-windows/Generic/BallisticaCore.ico: .efrocachemap
 	@tools/pcommand efrocache_get $@
 
-ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.exe: \
-   ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.lib \
-   ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.pdb \
-   ballisticacore-windows/Generic/BallisticaCore.ico \
-   prereqs code resources
+windows-wsl-debug-build: \
+   prereqs code resources \
+   build/prefab/lib/windows/Debug_Win32/BallisticaCoreGenericInternal.lib \
+   build/prefab/lib/windows/Debug_Win32/BallisticaCoreGenericInternal.pdb \
+   ballisticacore-windows/Generic/BallisticaCore.ico
 	WINDOWS_PROJECT=Generic WINDOWS_CONFIGURATION=Debug WINDOWS_PLATFORM=$* \
-      ${MAKE} _windows-wsl-build
+  ${MAKE} _windows-wsl-build
 
 # These are 'intermediate' files and will get deleted implicitly by make
 # if we don't do this.
 # See: https://www.gnu.org/software/make/manual/make.html#Special-Targets
-.PRECIOUS: \
-   ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.lib \
-   ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.pdb
+# .PRECIOUS: \
+#    ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.lib \
+#    ballisticacore-windows/build/Debug_%/BallisticaCoreGenericInternal.pdb
 
 # Tell make which of these targets don't represent files.
 .PHONY: prefab-debug prefab-release prefab-debug-build prefab-release-build \
@@ -755,6 +755,30 @@ WINDOWS_PLATFORM ?= Win32
 # Can be Debug or Release
 WINDOWS_CONFIGURATION ?= Debug
 
+# Base dir for all windows asset staging, intermediate files, and builds.
+# Note: this value only applies to MSBuild compiles when launched through
+# this Makefile. If you build/debug directly from within Visual Studio,
+# its own project paths will be used instead. Those are set to line up
+# with the defaults here, but if you change one then you may need to
+# change the other. (or just always build via Makefile and things will
+# always line up).
+WINDOWS_BUILD_DIR ?= build/windows
+
+foof:
+	echo PTH $(shell tools/pcommand wsl_path_to_win --escape --create $(WOUTDIR))
+
+# Remove all non-git-managed files in windows subdir.
+windows-clean:
+	@${CHECK_CLEAN_SAFETY}
+	git clean -dfx ballisticacore-windows
+	rm -rf ${WINDOWS_BUILD_DIR} ${LAZYBUILDDIR}
+
+# Show what would be cleaned.
+windows-clean-list:
+	@${CHECK_CLEAN_SAFETY}
+	git clean -dnx ballisticacore-windows
+	echo would also remove ${WINDOWS_BUILD_DIR} ${LAZYBUILDDIR}
+
 
 ################################################################################
 #                                                                              #
@@ -884,6 +908,8 @@ WIN_MSBUILD_EXE_B = "${_WMSBE_1B}${_WMSBE_2B}"
 WINPRJ = $(WINDOWS_PROJECT)
 WINPLT = $(WINDOWS_PLATFORM)
 WINCFG = $(WINDOWS_CONFIGURATION)
+WOUTDIR = $(WINDOWS_BUILD_DIR)/$(WINCFG)_$(WINPLT)/
+WINTDIR = $(WINDOWS_BUILD_DIR)/obj/BallisticaCore$(WINPRJ)/$(WINCFG)_$(WINPLT)/
 
 # When using CLion, our cmake dir is root. Expose .clang-format there too.
 ballisticacore-cmake/.clang-format: .clang-format
@@ -918,17 +944,29 @@ _cmake-simple-ci-server-build:
 
 _windows-wsl-build:
 	${WIN_MSBUILD_EXE_B} \
-  ${shell tools/pcommand wsl_to_escaped_win_path \
-  ballisticacore-windows/${WINPRJ}/BallisticaCore${WINPRJ}.vcxproj} \
-  -target:Build -property:Configuration=${WINCFG} \
-  -property:Platform=${WINPLT} ${VISUAL_STUDIO_VERSION}
+  ${shell tools/pcommand wsl_path_to_win --escape \
+   ballisticacore-windows/${WINPRJ}/BallisticaCore${WINPRJ}.vcxproj} \
+  -target:Build \
+  -property:Configuration=${WINCFG} \
+  -property:Platform=${WINPLT} \
+  -property:IntDir=$(shell tools/pcommand wsl_path_to_win \
+   --escape --create $(WINTDIR)) \
+  -property:OutDir=$(shell tools/pcommand wsl_path_to_win \
+   --escape --create $(WOUTDIR)) \
+  ${VISUAL_STUDIO_VERSION}
 
 _windows-wsl-rebuild:
 	${WIN_MSBUILD_EXE_B} \
-  ${shell tools/pcommand wsl_to_escaped_win_path \
-  ballisticacore-windows/${WINPRJ}/BallisticaCore${WINPRJ}.vcxproj} \
-  -target:Rebuild -property:Configuration=${WINCFG} \
-  -property:Platform=${WINPLT} ${VISUAL_STUDIO_VERSION}
+  ${shell tools/pcommand wsl_path_to_win --escape \
+   ballisticacore-windows/${WINPRJ}/BallisticaCore${WINPRJ}.vcxproj} \
+  -target:Rebuild \
+  -property:Configuration=${WINCFG} \
+  -property:Platform=${WINPLT} \
+  -property:IntDir=$(shell tools/pcommand wsl_path_to_win \
+   --escape --create $(WINTDIR)) \
+  -property:OutDir=$(shell tools/pcommand wsl_path_to_win \
+   --escape --create $(WOUTDIR)) \
+  ${VISUAL_STUDIO_VERSION}
 
 # Tell make which of these targets don't represent files.
 .PHONY: _cmake-simple-ci-server-build _windows-wsl-build _windows-wsl-rebuild
diff --git a/ballisticacore-windows/Generic/BallisticaCoreGeneric.vcxproj b/ballisticacore-windows/Generic/BallisticaCoreGeneric.vcxproj
index 6011ac83..ab91419a 100644
--- a/ballisticacore-windows/Generic/BallisticaCoreGeneric.vcxproj
+++ b/ballisticacore-windows/Generic/BallisticaCoreGeneric.vcxproj
@@ -727,7 +727,7 @@
     <ResourceCompile Include="BallisticaCore.rc" />
   </ItemGroup>
   <ItemGroup>
-    <Library Include="..\build\$(Configuration)_$(Platform)\$(MSBuildProjectName)Internal.lib" />
+    <Library Include="..\..\build\prefab\lib\windows\$(Configuration)_$(Platform)\$(MSBuildProjectName)Internal.lib" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
diff --git a/ballisticacore-windows/Headless/BallisticaCoreHeadless.vcxproj b/ballisticacore-windows/Headless/BallisticaCoreHeadless.vcxproj
index fa22160c..cd4bac56 100644
--- a/ballisticacore-windows/Headless/BallisticaCoreHeadless.vcxproj
+++ b/ballisticacore-windows/Headless/BallisticaCoreHeadless.vcxproj
@@ -72,22 +72,22 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(ProjectDir)..\build\$(Configuration)_$(Platform)\</OutDir>
-    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Platform)_$(Configuration)\</IntDir>
+    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Configuration)_$(Platform)\</IntDir>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(ProjectDir)..\build\$(Configuration)_$(Platform)\</OutDir>
-    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Platform)_$(Configuration)\</IntDir>
+    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Configuration)_$(Platform)\</IntDir>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <OutDir>$(ProjectDir)..\build\$(Configuration)_$(Platform)\</OutDir>
-    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Platform)_$(Configuration)\</IntDir>
+    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Configuration)_$(Platform)\</IntDir>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
     <LinkIncremental>false</LinkIncremental>
     <OutDir>$(ProjectDir)..\build\$(Configuration)_$(Platform)\</OutDir>
-    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Platform)_$(Configuration)\</IntDir>
+    <IntDir>$(ProjectDir)..\build\obj\$(MSBuildProjectName)\$(Configuration)_$(Platform)\</IntDir>
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
@@ -181,7 +181,7 @@
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup>
-    <Library Include="..\build\$(Configuration)_$(Platform)\$(MSBuildProjectName)Internal.lib" />
+    <Library Include="..\..\build\prefab\lib\windows\$(Configuration)_$(Platform)\$(MSBuildProjectName)Internal.lib" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\src\ballistica\app\app.cc" />
diff --git a/tools/batools/pcommand.py b/tools/batools/pcommand.py
index 9282cbae..a1d874ac 100644
--- a/tools/batools/pcommand.py
+++ b/tools/batools/pcommand.py
@@ -474,23 +474,56 @@ def checkenv() -> None:
     batools.build.checkenv()
 
 
-def wsl_to_escaped_win_path() -> None:
+def wsl_path_to_win() -> None:
     """Forward escape slashes in a provided win path arg."""
     import subprocess
+    import logging
+    import os
     from efro.error import CleanError
-    if len(sys.argv) != 3:
-        raise CleanError('Expected 1 path arg.')
     try:
-        out = subprocess.run(['wslpath', '-w', '-a', sys.argv[2]],
-                             capture_output=True,
-                             check=True)
+        print('HELLO FROM WSL_PATH_TO_WIN', file=sys.stderr)
+        create = False
+        escape = False
+        if len(sys.argv) < 3:
+            raise CleanError('Expected at least 1 path arg.')
+        wsl_path: Optional[str] = None
+        for arg in sys.argv[2:]:
+            if arg == '--create':
+                create = True
+            elif arg == '--escape':
+                escape = True
+            else:
+                if wsl_path is not None:
+                    raise CleanError('More than one path provided.')
+                wsl_path = arg
+        if wsl_path is None:
+            raise CleanError('No path provided.')
+
+        # wslpath fails on nonexistent paths; make it clear when that happens.
+        if create:
+            os.makedirs(wsl_path, exist_ok=True)
+        if not os.path.exists(wsl_path):
+            raise CleanError(f'Path \'{wsl_path}\' does not exist.')
+
+        results = subprocess.run(['wslpath', '-w', '-a', wsl_path],
+                                 capture_output=True,
+                                 check=True)
     except Exception:
         # This gets used in a makefile so our returncode is ignored;
-        # try to convey failure in other ways.
+        # let's try to make our failure known in other ways.
+        logging.exception('wsl_to_escaped_win_path failed.')
         print('wsl_to_escaped_win_path_error_occurred', end='')
         return
 
-    print(out.stdout.decode().strip().replace('\\', '\\\\'), end='')
+    out = results.stdout.decode().strip()
+
+    # If our input ended with a slash, match in the output.
+    if wsl_path.endswith('/') and not out.endswith('\\'):
+        out += '\\'
+
+    if escape:
+        out = out.replace('\\', '\\\\')
+    print(out, end='')
 
 
 def ensure_build_platform() -> None:
diff --git a/tools/pcommand b/tools/pcommand
index 5e145b8b..b1e9e47d 100755
--- a/tools/pcommand
+++ b/tools/pcommand
@@ -38,7 +38,7 @@ from batools.pcommand import (
     make_prefab, update_makebob, lazybuild, android_archive_unstripped_libs,
     efro_gradle, stage_assets, update_assets_makefile, update_project,
     update_cmake_prefab_lib, cmake_prep_dir, gen_binding_code,
-    gen_flat_data_code, wsl_to_escaped_win_path)
+    gen_flat_data_code, wsl_path_to_win)
 # pylint: enable=unused-import
 
 if TYPE_CHECKING: