diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index df0a4a77..6d7a612d 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -27,48 +27,33 @@ jobs:
           sudo apt -y --allow-downgrades install g++-10-multilib linux-libc-dev binutils-arm-none-eabi p7zip-full pkg-config libpugixml-dev ppa-purge
           sudo ppa-purge -y ppa:ubuntu-toolchain-r/test || true
           sudo dpkg --add-architecture i386
-          sudo mkdir -pm755 /etc/apt/keyrings
-          sudo wget -O /etc/apt/keyrings/winehq-archive.key https://dl.winehq.org/wine-builds/winehq.key
-          sudo add-apt-repository ppa:cybermax-dexter/sdl2-backport
-          sudo wget -NP /etc/apt/sources.list.d/ https://dl.winehq.org/wine-builds/ubuntu/dists/$(lsb_release -cs)/winehq-$(lsb_release -cs).sources
           sudo apt update
-          sudo apt -y --allow-downgrades install --install-recommends winehq-stable
+          sudo apt -y --allow-downgrades install libc6:i386
 
       - name: Checkout repo
         uses: actions/checkout@v4
 
       - name: Set up repo
         run: |
-          mkdir -p ~/download
-          cd ~/download
-          wget https://github.com/pret/pmd-sky/raw/workflows/assets/mwccarm.zip
-          wget https://github.com/pret/pmd-sky/raw/workflows/assets/NitroSDK-4_2-071210-jp.7z
-          unzip mwccarm.zip
-          mv mwccarm $GITHUB_WORKSPACE/tools
-          7z x NitroSDK-4_2-071210-jp.7z
-          mv tools/bin $GITHUB_WORKSPACE/tools
-          mv include/nitro/specfiles/ARM7-TS.lcf.template $GITHUB_WORKSPACE/sub/
-          mv include/nitro/specfiles/ARM9-TS.lcf.template $GITHUB_WORKSPACE/
-          mv include/nitro/specfiles/mwldarm.response.template $GITHUB_WORKSPACE/
-        working-directory: ~
+          make install_toolchain install_wibo install_metroskrew
 
       - name: Build North America
         env:
           GAME_LANGUAGE: NORTH_AMERICA
           GAME_REVISION: 0
-        run: make -j${nproc}
+        run: make -j${nproc} USE_WIBO=1 USE_METROSKREW=1
 
       - name: Build Europe
         env:
           GAME_LANGUAGE: EUROPE
           GAME_REVISION: 0
-        run: make -j${nproc}
+        run: make -j${nproc} USE_WIBO=1 USE_METROSKREW=1
 
       - name: Build Japan
         env:
           GAME_LANGUAGE: JAPAN
           GAME_REVISION: 0
-        run: make -j${nproc}
+        run: make -j${nproc} USE_WIBO=1 USE_METROSKREW=1
 
       - name: Webhook
         if: ${{ github.event_name == 'push' && env.CALCROM_WEBHOOK_URL != '' }}
diff --git a/.gitignore b/.gitignore
index 2ea2503c..f354f18f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,12 @@ tools/bin/**
 *.lcf.template
 *.response.template
 
+# wibo
+tools/wibo/**
+
+# metroskrew
+tools/metroskrew/**
+
 # Build folder
 build/**
 sub/build/**
diff --git a/INSTALL.md b/INSTALL.md
index fe5dd65a..de7859c9 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -104,6 +104,45 @@ There are targets for building and testing changes to individual components with
 
 At the end of building each of these, there is a checksum verification step. This makes sure that the final product is byte-for-byte equivalent to the retail ROM. To disable this, append `COMPARE=0` to your command.
 
+### Building with wibo and Metroskrew instead of wine
+
+**[wibo](https://github.com/decompals/wibo)** is a minimal and fast Win32 loader for decompilation work specifically. You can use it instead of wine on Linux (and x86 macOS, though untested).
+
+```shell
+make install_wibo   # download wibo into tools/wibo/
+make USE_WIBO=1     # build
+```
+
+To use wibo already on your `PATH`, pass `WIBO=wibo`:
+
+```shell
+make USE_WIBO=1 WIBO=wibo
+```
+
+Likewise, to use your own build, replace that with `WIBO=<path to your wibo binary>`.
+
+If the Nitro SDK tools (`makerom`, `makelcf`, `makebanner`) cause issues under wibo, you can use wine for those while keeping wibo on the Metrowerks binaries:
+
+```shell
+make USE_WIBO=1 NITROWINE=wine
+```
+
+**[Metroskrew](https://github.com/mid-kid/metroskrew)** is a port of the Metrowerks ARM compiler to Linux by relinking, which means that you can run the compilers directly as native Linux binaries using it.
+
+You will still need either Wine or Wibo for the SDK tools (which are separate from the compiler).
+
+In addition, Metroskrew's binaries are 32-bit x86, so you will need 32-bit glibc installed. That's:
+
+* libc6-i386 on Debian/Ubuntu
+* lib32-glibc on Arch (multilib)
+* glibc.i686 on Fedora
+
+```shell
+make install_metroskrew                  # download Metroskrew into tools/metroskrew/
+#make install_wibo                       # download wibo into tools/wibo/, from earlier
+make USE_WIBO=1 USE_METROSKREW=1         # build
+```
+
 ### Windows
 
 If you get an error in saving configuration settings when specifying the license file, you need to add a system environment variable called `LM_LICENSE_FILE` and point it to the `license.dat` file. Alternatively, run `mwccarm.exe` from an Administrator command prompt, PowerShell, or WSL session.
diff --git a/Makefile b/Makefile
index 567a9a7d..16f94dac 100644
--- a/Makefile
+++ b/Makefile
@@ -56,14 +56,14 @@ $(BUILD_DIR)/component.files: main ;
 $(HEADER_TEMPLATE): ;
 
 $(ROM): $(ROMSPEC) tools filesystem main sub $(BANNER)
-	$(WINE) $(MAKEROM) $(MAKEROM_FLAGS) -DBUILD_DIR=$(BUILD_DIR) -M$(NITROFS_FILES_FILE) -DTITLE_NAME="$(TITLE_NAME)" -DBNR="$(BANNER)" -DHEADER_TEMPLATE="$(HEADER_TEMPLATE)" $< $@
+	$(NITROWINE) $(MAKEROM) $(MAKEROM_FLAGS) -DBUILD_DIR=$(BUILD_DIR) -M$(NITROFS_FILES_FILE) -DTITLE_NAME="$(TITLE_NAME)" -DBNR="$(BANNER)" -DHEADER_TEMPLATE="$(HEADER_TEMPLATE)" $< $@
 	$(FIXROM) $@ --secure-crc $(SECURE_CRC) --game-code $(GAME_CODE)
 ifeq ($(COMPARE),1)
 	$(SHA1SUM) -c $(buildname)/rom.sha1
 endif
 
 $(BANNER): $(BANNER_SPEC) $(ICON_PNG:%.png=%.nbfp) $(ICON_PNG:%.png=%.nbfc)
-	$(WINE) $(MAKEBNR) $< $@
+	$(NITROWINE) $(MAKEBNR) $< $@
 
 us: ; @$(MAKE) GAME_LANGUAGE=NORTH_AMERICA
 eu: ; @$(MAKE) GAME_LANGUAGE=EUROPE
@@ -88,4 +88,25 @@ install_toolchain:
 	mv toolchain_tmp/nitro_sdk/include/nitro/specfiles/mwldarm.response.template .
 	rm -r toolchain_tmp
 
-.PHONY: compare install_toolchain
+WIBO_VERSION := 1.2.0
+WIBO_ARCH    := $(if $(filter aarch64 arm64,$(shell uname -m)),,$(if $(filter Darwin,$(shell uname -s)),macos,x86_64))
+
+install_wibo:
+ifeq ($(WIBO_ARCH),)
+	$(error No prebuilt wibo binaries are available for $(shell uname -s)/$(shell uname -m), build it from https://github.com/decompals/wibo and install it manually)
+endif
+	rm -rf tools/wibo
+	mkdir -p tools/wibo
+	wget -O tools/wibo/wibo https://github.com/decompals/wibo/releases/download/$(WIBO_VERSION)/wibo-$(WIBO_ARCH)
+	chmod +x tools/wibo/wibo
+	tools/wibo/wibo --version
+
+METROSKREW_VER ?= 0.1.3
+METROSKREW_URL := https://github.com/mid-kid/metroskrew/releases/download/$(METROSKREW_VER)/metroskrew-linux.tar.xz
+
+install_metroskrew:
+	rm -rf tools/metroskrew
+	mkdir -p tools/metroskrew
+	wget -O- $(METROSKREW_URL) | tar -xJ -C tools/metroskrew --strip-components=1
+
+.PHONY: compare install_toolchain install_wibo install_metroskrew
diff --git a/common.mk b/common.mk
index 79b2dff0..10e6f205 100644
--- a/common.mk
+++ b/common.mk
@@ -31,9 +31,19 @@ include $(WORK_DIR)/platform.mk
 include $(WORK_DIR)/binutils.mk
 
 # NitroSDK tools
-MWCC          = $(TOOLSDIR)/mwccarm/$(MWCCVER)/mwccarm.exe
-MWAS          = $(TOOLSDIR)/mwccarm/$(MWCCVER)/mwasmarm.exe
-MWLD          = $(BACK_REL)/$(TOOLSDIR)/mwccarm/$(MWCCVER)/mwldarm.exe
+MWAS_EXE      = $(TOOLSDIR)/mwccarm/$(MWCCVER)/mwasmarm.exe
+ifneq ($(USE_METROSKREW),0)
+  SKREWRAP     := $(abspath $(TOOLSDIR)/metroskrew/bin/skrewrap)
+  SKREW_SDK     = $(TOOLSDIR)/metroskrew/share/metroskrew/sdk/ds/$(MWCCVER)
+  skrew_ver     = $(patsubst $(1)-%.exe,%,$(shell cat $(SKREW_SDK)/$(1).exe.txt))
+  MWCC          = $(SKREWRAP) mwccarm -wrap:ver $(call skrew_ver,mwccarm)
+  MWAS          = $(SKREWRAP) mwasmarm -wrap:ver $(call skrew_ver,mwasmarm)
+  MWLD          = $(SKREWRAP) mwldarm -wrap:ver $(call skrew_ver,mwldarm)
+else
+  MWCC          = $(WINE) $(TOOLSDIR)/mwccarm/$(MWCCVER)/mwccarm.exe
+  MWAS          = $(WINE) $(TOOLSDIR)/mwccarm/$(MWCCVER)/mwasmarm.exe
+  MWLD          = $(WINE) $(BACK_REL)/$(TOOLSDIR)/mwccarm/$(MWCCVER)/mwldarm.exe
+endif
 MAKEROM      := $(TOOLSDIR)/bin/makerom.exe
 MAKELCF      := $(TOOLSDIR)/bin/makelcf.exe
 MAKEBNR      := $(TOOLSDIR)/bin/makebanner.exe
@@ -146,11 +156,11 @@ LIBRARY_INCLUDE_FLAGS := -I$(WORK_DIR)/lib/msl/include/MSL_C $(foreach dname,$(L
 SRC_INCLUDE_FLAGS := -i ./include -i ./include/library -i $(WORK_DIR)/files $(LIBRARY_INCLUDE_FLAGS)
 SDK_INCLUDE_FLAGS := $(LIBRARY_INCLUDE_FLAGS)
 
-MW_COMPILE_SRC = $(WINE) $(MWCC) $(OPTFLAGS) $(MWCFLAGS) $(SRC_INCLUDE_FLAGS) -i $(PRECOMPILE_OBJ_DIR) -prefix $(PRECOMPILE_OBJ_BASENAME)
-MW_COMPILE_LIB = $(WINE) $(MWCC) $(OPTFLAGS_SDK) $(MWCFLAGS_LIB) $(SRC_INCLUDE_FLAGS) -i $(PRECOMPILE_OBJ_DIR) -prefix $(PRECOMPILE_OBJ_BASENAME)
-MW_COMPILE_SRC_PRECOMPILE = $(WINE) $(MWCC) $(MWCFLAGS) $(SRC_INCLUDE_FLAGS)
+MW_COMPILE_SRC = $(MWCC) $(OPTFLAGS) $(MWCFLAGS) $(SRC_INCLUDE_FLAGS) -i $(PRECOMPILE_OBJ_DIR) -prefix $(PRECOMPILE_OBJ_BASENAME)
+MW_COMPILE_LIB = $(MWCC) $(OPTFLAGS_SDK) $(MWCFLAGS_LIB) $(SRC_INCLUDE_FLAGS) -i $(PRECOMPILE_OBJ_DIR) -prefix $(PRECOMPILE_OBJ_BASENAME)
+MW_COMPILE_SRC_PRECOMPILE = $(MWCC) $(MWCFLAGS) $(SRC_INCLUDE_FLAGS)
 
-MW_ASSEMBLE = $(WINE) $(MWAS) $(MWASFLAGS)
+MW_ASSEMBLE = $(MWAS) $(MWASFLAGS)
 
 export MWCIncludes := lib/include
 
@@ -171,8 +181,8 @@ DUMMY := $(shell mkdir -p $(ALL_BUILDDIRS) $(PRECOMPILE_OBJ_DIR))
 .PRECIOUS: $(SBIN)
 .NOTPARALLEL:
 
-.PHONY: $(MWAS)
-$(MWAS):
+.PHONY: $(MWAS_EXE)
+$(MWAS_EXE):
 	$(ASPATCH) -q $@
 
 ifeq ($(NODEP),)
@@ -224,7 +234,7 @@ $(BUILD_DIR)/lib/%.o: lib/%.c $(BUILD_DIR)/lib/%.d $(NITRO_PRECOMPILE_OBJ)
 
 $(BUILD_DIR)/%.o: %.s
 $(BUILD_DIR)/%.o: %.s $(BUILD_DIR)/%.d
-	$(WINE) $(MWAS) $(MWASFLAGS) -I$(dir $<) $(DEPFLAGS) -o $@ $<
+	$(MWAS) $(MWASFLAGS) -I$(dir $<) $(DEPFLAGS) -o $@ $<
 	@$(call fixdep,$(BUILD_DIR)/$*.d)
 
 include $(wildcard $(DEPFILES))
@@ -237,12 +247,12 @@ $(BUILD_DIR)/%.o: %.c
 	$(BUILD_C) $@ $<
 
 $(BUILD_DIR)/%.o: %.s
-	$(WINE) $(MWAS) $(MWASFLAGS) -o $@ $<
+	$(MWAS) $(MWASFLAGS) -o $@ $<
 endif
 
 $(NATIVE_TOOLS): tools
 
-tools: $(TOOLDIRS) $(MWAS)
+tools: $(TOOLDIRS) $(MWAS_EXE)
 
 $(TOOLDIRS):
 	@$(MAKE) -C $@
@@ -251,7 +261,7 @@ clean-tools:
 	$(foreach tool,$(TOOLDIRS),$(MAKE) -C $(tool) clean;)
 
 $(LCF): $(LSF) $(LCF_TEMPLATE)
-	$(WINE) $(MAKELCF) $(MAKELCF_FLAGS) $^ $@
+	$(NITROWINE) $(MAKELCF) $(MAKELCF_FLAGS) $^ $@
 ifeq ($(PROC),arm946e)
 	$(SED) -i '1i KEEP_SECTION\n{\n\t.exceptix\n}' $@
 else
@@ -262,13 +272,13 @@ RESPONSE_TEMPLATE    := $(PROJECT_ROOT)/mwldarm.response.template
 RESPONSE_TEMPLATE_NT := $(PROJECT_ROOT_NT)/mwldarm.response.template
 
 $(RESPONSE): $(LSF) $(RESPONSE_TEMPLATE)
-	$(WINE) $(MAKELCF) $(MAKELCF_FLAGS) $< $(RESPONSE_TEMPLATE_NT) $@
+	$(NITROWINE) $(MAKELCF) $(MAKELCF_FLAGS) $< $(RESPONSE_TEMPLATE_NT) $@
 
 # Locate crt0.o
 CRT0_OBJ := lib/asm/crt0.o
 
 $(NEF): $(LCF) $(RESPONSE) $(ALL_OBJS)
-	cd $(BUILD_DIR) && LM_LICENSE_FILE=$(BACK_REL)/$(LM_LICENSE_FILE) $(WINE) $(MWLD) $(MWLDFLAGS) $(LIBS) -o $(BACK_REL)/$(NEF) $(LCF:$(BUILD_DIR)/%=%) @$(RESPONSE:$(BUILD_DIR)/%=%) $(CRT0_OBJ)
+	cd $(BUILD_DIR) && LM_LICENSE_FILE=$(BACK_REL)/$(LM_LICENSE_FILE) $(MWLD) $(MWLDFLAGS) $(LIBS) -o $(BACK_REL)/$(NEF) $(LCF:$(BUILD_DIR)/%=%) @$(RESPONSE:$(BUILD_DIR)/%=%) $(CRT0_OBJ)
 
 .INTERMEDIATE: $(BUILD_DIR)/obj.list
 
diff --git a/lib/syscall/Makefile b/lib/syscall/Makefile
index 2d1a0dd8..bbe64ccf 100644
--- a/lib/syscall/Makefile
+++ b/lib/syscall/Makefile
@@ -20,7 +20,7 @@ all: $(LIB)
 ASM_SRCS    := asm/_secure_$(GAME_CODE).s
 
 $(LIB): $(ALL_OBJS)
-	cd $(BUILD_DIR) && LM_LICENSE_FILE=$(BACK_REL)/$(LM_LICENSE_FILE) $(WINE) $(MWLD) $(MWLDFLAGS) -o $(BACK_REL)/$(LIB) $(ALL_OBJS:$(BUILD_DIR)/%=%)
+	cd $(BUILD_DIR) && LM_LICENSE_FILE=$(BACK_REL)/$(LM_LICENSE_FILE) $(MWLD) $(MWLDFLAGS) -o $(BACK_REL)/$(LIB) $(ALL_OBJS:$(BUILD_DIR)/%=%)
 
 install: all
 	$(shell mkdir -p $(INSTALL_LIBDIR))
diff --git a/main.lsf b/main.lsf
index 8dd27efe..cd35d5fd 100644
--- a/main.lsf
+++ b/main.lsf
@@ -445,7 +445,7 @@ Static main
     Object lib/NitroSDK/asm/os_valarm.o
 	Object lib/NitroSDK/src/os/os_system.o
 	object lib/NitroSDK/asm/os_reset.o
-	object lib/NitroSDK/src/os/os_ownerinfo.o
+	object lib/NitroSDK/src/os/os_ownerInfo.o
 	Object lib/NitroSDK/src/os/os_vramExclusive.o
 	Object lib/NitroSDK/src/os/os_entropy.o
 	Object lib/NitroSDK/src/os/os_terminate_proc.o
diff --git a/platform.mk b/platform.mk
index 5493e631..152ca331 100644
--- a/platform.mk
+++ b/platform.mk
@@ -44,3 +44,34 @@ ifeq ($(NOWINE),1)
 else
   WINPATH := winepath
 endif
+
+# Win32 runner selection, using wibo when USE_WIBO=1 and regular wine otherwise.
+#
+#   make install_wibo      # download wibo in tools/wibo/
+#   make USE_WIBO=1        # build
+#
+# WIBO overrides which binary is used; it defaults to tools/wibo/* when present and otherwise to `wibo` on PATH.
+#
+# Nitro SDK tools are run using NITROWINE. It can be set separately like so:
+#
+#   make USE_WIBO=1 NITROWINE=wine
+#
+# if you find that WIBO doesn't work as well with those tools as compared to the Metrowerks compilers.
+
+USE_WIBO ?= 0
+
+ifneq ($(USE_WIBO),0)
+  TOOLS_WIBO    := $(TOOLSDIR)/wibo/wibo
+  WIBO          ?= $(if $(wildcard $(TOOLS_WIBO)),$(TOOLS_WIBO),wibo)
+  # Make the path absolute as long as it's not just "wibo" (from PATH)
+  WIBO_CMD      := $(if $(findstring /,$(WIBO)),$(abspath $(WIBO)),$(WIBO))
+  WINE          := $(WIBO_CMD)
+  WINPATH       := $(WIBO_CMD) path      # use `wibo path` under wibo instead of winepath
+endif
+
+NITROWINE ?= $(WINE)
+
+# USE_METROSKREW overrides WINE for the Metrowerks compilers only,
+# skipping wine entirely, using the metroskrew native re-link.
+
+USE_METROSKREW ?= 0