diff --git a/compat/mingw.c b/compat/mingw.c
index 6accd26f2a9808..9891950d4ed115 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3625,7 +3625,7 @@ int xwcstoutf(char *utf, const wchar_t *wcs, size_t utflen)
 }
 
 #ifdef ENSURE_MSYSTEM_IS_SET
-#if !defined(RUNTIME_PREFIX) || !defined(HAVE_WPGMPTR)
+#if !defined(RUNTIME_PREFIX) || !defined(HAVE_WPGMPTR) || !defined(MINGW_PREFIX)
 static size_t append_system_bin_dirs(char *path UNUSED, size_t size UNUSED)
 {
 	return 0;
@@ -3643,25 +3643,16 @@ static size_t append_system_bin_dirs(char *path, size_t size)
 	/* strip trailing `git.exe` */
 	len = slash - prefix;
 
-	/* strip trailing `cmd` or `mingw64\bin` or `mingw32\bin` or `bin` or `libexec\git-core` */
-	if (strip_suffix_mem(prefix, &len, "\\mingw64\\libexec\\git-core") ||
-	    strip_suffix_mem(prefix, &len, "\\mingw64\\bin"))
+	/* strip trailing `cmd` or `<mingw-prefix>\bin` or `bin` or `libexec\git-core` */
+	if (strip_suffix_mem(prefix, &len, "\\" MINGW_PREFIX "\\libexec\\git-core") ||
+	    strip_suffix_mem(prefix, &len, "\\" MINGW_PREFIX "\\bin"))
 		off += xsnprintf(path + off, size - off,
-				 "%.*s\\mingw64\\bin;", (int)len, prefix);
-	else if (strip_suffix_mem(prefix, &len, "\\clangarm64\\libexec\\git-core") ||
-	    strip_suffix_mem(prefix, &len, "\\clangarm64\\bin"))
-		off += xsnprintf(path + off, size - off,
-				 "%.*s\\clangarm64\\bin;", (int)len, prefix);
-	else if (strip_suffix_mem(prefix, &len, "\\mingw32\\libexec\\git-core") ||
-		 strip_suffix_mem(prefix, &len, "\\mingw32\\bin"))
-		off += xsnprintf(path + off, size - off,
-				 "%.*s\\mingw32\\bin;", (int)len, prefix);
+				 "%.*s\\" MINGW_PREFIX "\\bin;", (int)len, prefix);
 	else if (strip_suffix_mem(prefix, &len, "\\cmd") ||
 		 strip_suffix_mem(prefix, &len, "\\bin") ||
 		 strip_suffix_mem(prefix, &len, "\\libexec\\git-core"))
 		off += xsnprintf(path + off, size - off,
-				 "%.*s\\mingw%d\\bin;", (int)len, prefix,
-				 (int)(sizeof(void *) * 8));
+				 "%.*s\\" MINGW_PREFIX "\\bin;", (int)len, prefix);
 	else
 		return 0;
 
@@ -3757,13 +3748,7 @@ static void setup_windows_environment(void)
 		char buf[32768];
 		size_t off = 0;
 
-#if defined(__aarch64__) || defined(_M_ARM64) || defined(_M_ARM64EC)
-		setenv("MSYSTEM", "CLANGARM64", 1);
-#elif defined(__MINGW64__) || defined(_M_AMD64)
-		setenv("MSYSTEM", "MINGW64", 1);
-#else
-		setenv("MSYSTEM", "MINGW32", 1);
-#endif
+		setenv("MSYSTEM", ENSURE_MSYSTEM_IS_SET, 1);
 
 		if (home)
 			off += xsnprintf(buf + off, sizeof(buf) - off,
diff --git a/config.mak.uname b/config.mak.uname
index b28e40caff6ae9..ba399c22fbfc56 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -452,14 +452,8 @@ ifeq ($(uname_S),Windows)
 	GIT_VERSION := $(GIT_VERSION).MSVC
 	pathsep = ;
 	# Assume that this is built in Git for Windows' SDK
-        ifeq (MINGW32,$(MSYSTEM))
-		prefix = /mingw32
-        else
-                ifeq (CLANGARM64,$(MSYSTEM))
-			prefix = /clangarm64
-                else
-			prefix = /mingw64
-                endif
+        ifneq (,$(MSYSTEM))
+		prefix = $(MINGW_PREFIX)
         endif
 	# Prepend MSVC 64-bit tool-chain to PATH.
 	#
@@ -513,7 +507,7 @@ ifeq ($(uname_S),Windows)
 	NATIVE_CRLF = YesPlease
 	DEFAULT_HELP_FORMAT = html
 	SKIP_DASHED_BUILT_INS = YabbaDabbaDoo
-ifeq (/mingw64,$(subst 32,64,$(subst clangarm,mingw,$(prefix))))
+ifneq (,$(MINGW_PREFIX))
 	# Move system config into top-level /etc/
 	ETC_GITCONFIG = ../etc/gitconfig
 	ETC_GITATTRIBUTES = ../etc/gitattributes
@@ -529,7 +523,9 @@ endif
 		compat/win32/pthread.o compat/win32/syslog.o \
 		compat/win32/trace2_win32_process_info.o \
 		compat/win32/dirent.o compat/win32/fscache.o compat/win32/wsl.o
-	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DENSURE_MSYSTEM_IS_SET -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
+	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY \
+		-DENSURE_MSYSTEM_IS_SET="\"$(MSYSTEM)\"" -DMINGW_PREFIX="\"$(patsubst /%,%,$(MINGW_PREFIX))\"" \
+		-DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
 	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO
 	# invalidcontinue.obj allows Git's source code to close the same file
 	# handle twice, or to access the osfhandle of an already-closed stdout
@@ -747,26 +743,25 @@ ifeq ($(uname_S),MINGW)
         ifneq (,$(findstring -O,$(filter-out -O0 -Og,$(CFLAGS))))
 		BASIC_LDFLAGS += -Wl,--dynamicbase
         endif
-        ifeq (MINGW32,$(MSYSTEM))
-		prefix = /mingw32
-		HOST_CPU = i686
-		BASIC_LDFLAGS += -Wl,--pic-executable,-e,_mainCRTStartup
-        endif
-        ifeq (MINGW64,$(MSYSTEM))
-		prefix = /mingw64
-		HOST_CPU = x86_64
-		BASIC_LDFLAGS += -Wl,--pic-executable,-e,mainCRTStartup
-        else ifeq (CLANGARM64,$(MSYSTEM))
-		prefix = /clangarm64
-		HOST_CPU = aarch64
-		BASIC_LDFLAGS += -Wl,--pic-executable,-e,mainCRTStartup
-        else
-		COMPAT_CFLAGS += -D_USE_32BIT_TIME_T
-		BASIC_LDFLAGS += -Wl,--large-address-aware
+        ifneq (,$(MSYSTEM))
+                ifeq ($(MINGW_PREFIX),$(filter-out /%,$(MINGW_PREFIX)))
+			# Override if empty or does not start with a slash
+			MINGW_PREFIX := /$(shell echo '$(MSYSTEM)' | tr A-Z a-z)
+                endif
+		prefix = $(MINGW_PREFIX)
+		HOST_CPU = $(patsubst %-w64-mingw32,%,$(MINGW_CHOST))
+		BASIC_LDFLAGS += -Wl,--pic-executable
+		COMPAT_CFLAGS += -DDETECT_MSYS_TTY \
+			-DENSURE_MSYSTEM_IS_SET="\"$(MSYSTEM)\"" \
+			-DMINGW_PREFIX="\"$(patsubst /%,%,$(MINGW_PREFIX))\""
+                ifeq (MINGW32,$(MSYSTEM))
+			BASIC_LDFLAGS += -Wl,--large-address-aware
+                endif
+		# Move system config into top-level /etc/
+		ETC_GITCONFIG = ../etc/gitconfig
+		ETC_GITATTRIBUTES = ../etc/gitattributes
         endif
-	CC = gcc
-	COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO=0 -DDETECT_MSYS_TTY \
-		-DENSURE_MSYSTEM_IS_SET -fstack-protector-strong
+	COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO=0 -fstack-protector-strong
 	EXTLIBS += -lntdll
 	EXTRA_PROGRAMS += headless-git$X
 	INSTALL = /bin/install
@@ -776,62 +771,6 @@ ifeq ($(uname_S),MINGW)
 	USE_LIBPCRE = YesPlease
 	USE_MIMALLOC = YesPlease
 	NO_PYTHON =
-        ifeq (/mingw64,$(subst 32,64,$(subst clangarm,mingw,$(prefix))))
-		# Move system config into top-level /etc/
-		ETC_GITCONFIG = ../etc/gitconfig
-		ETC_GITATTRIBUTES = ../etc/gitattributes
-        endif
-	MINGW_PREFIX := $(subst /,,$(prefix))
-
-	DESTDIR_WINDOWS = $(shell cygpath -aw '$(DESTDIR_SQ)')
-	DESTDIR_MIXED = $(shell cygpath -am '$(DESTDIR_SQ)')
-install-mingit-test-artifacts:
-	install -m755 -d '$(DESTDIR_SQ)/usr/bin'
-	printf '%s\n%s\n' >'$(DESTDIR_SQ)/usr/bin/perl' \
-		"#!/mingw64/bin/busybox sh" \
-		"exec \"$(shell cygpath -am /usr/bin/perl.exe)\" \"\$$@\""
-
-	install -m755 -d '$(DESTDIR_SQ)'
-	printf '%s%s\n%s\n%s\n%s\n%s\n' >'$(DESTDIR_SQ)/init.bat' \
-		"PATH=$(DESTDIR_WINDOWS)\\$(MINGW_PREFIX)\\bin;" \
-		"C:\\WINDOWS;C:\\WINDOWS\\system32" \
-		"@set GIT_TEST_INSTALLED=$(DESTDIR_MIXED)/$(MINGW_PREFIX)/bin" \
-		"@`echo "$(DESTDIR_WINDOWS)" | sed 's/:.*/:/'`" \
-		"@cd `echo "$(DESTDIR_WINDOWS)" | sed 's/^.://'`\\test-git\\t" \
-		"@echo Now, run 'helper\\test-run-command testsuite'"
-
-	install -m755 -d '$(DESTDIR_SQ)/test-git'
-	sed 's/^\(NO_PERL\|NO_PYTHON\)=.*/\1=YesPlease/' \
-		<GIT-BUILD-OPTIONS >'$(DESTDIR_SQ)/test-git/GIT-BUILD-OPTIONS'
-
-	install -m755 -d '$(DESTDIR_SQ)/test-git/t/helper'
-	install -m755 $(TEST_PROGRAMS) '$(DESTDIR_SQ)/test-git/t/helper'
-	(cd t && $(TAR) cf - t[0-9][0-9][0-9][0-9] lib-diff) | \
-	(cd '$(DESTDIR_SQ)/test-git/t' && $(TAR) xf -)
-	install -m755 t/t556x_common t/*.sh '$(DESTDIR_SQ)/test-git/t'
-
-	install -m755 -d '$(DESTDIR_SQ)/test-git/templates'
-	(cd templates && $(TAR) cf - blt) | \
-	(cd '$(DESTDIR_SQ)/test-git/templates' && $(TAR) xf -)
-
-	# po/build/locale for t0200
-	install -m755 -d '$(DESTDIR_SQ)/test-git/po/build/locale'
-	(cd po/build/locale && $(TAR) cf - .) | \
-	(cd '$(DESTDIR_SQ)/test-git/po/build/locale' && $(TAR) xf -)
-
-	# git-daemon.exe for t5802, git-http-backend.exe for t5560
-	install -m755 -d '$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
-	install -m755 git-daemon.exe git-http-backend.exe \
-		'$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
-
-	# git-upload-archive (dashed) for t5000
-	install -m755 -d '$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
-	install -m755 git-upload-archive.exe '$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
-
-	# git-difftool--helper for t7800
-	install -m755 -d '$(DESTDIR_SQ)/$(MINGW_PREFIX)/libexec/git-core'
-	install -m755 git-difftool--helper \
-		'$(DESTDIR_SQ)/$(MINGW_PREFIX)/libexec/git-core'
 endif
 ifeq ($(uname_S),QNX)
 	COMPAT_CFLAGS += -DSA_RESTART=0
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 6443dfbac52663..c69f3a7ea95667 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -282,7 +282,14 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
 				_CONSOLE DETECT_MSYS_TTY STRIP_EXTENSION=".exe"  NO_SYMLINK_HEAD UNRELIABLE_FSTAT
 				NOGDI OBJECT_CREATION_MODE=1 __USE_MINGW_ANSI_STDIO=0
 				USE_NED_ALLOCATOR OVERRIDE_STRDUP MMAP_PREVENTS_DELETE USE_WIN32_MMAP
-				HAVE_WPGMPTR ENSURE_MSYSTEM_IS_SET HAVE_RTLGENRANDOM)
+				HAVE_WPGMPTR HAVE_RTLGENRANDOM)
+	if(CMAKE_GENERATOR_PLATFORM STREQUAL "x64")
+		add_compile_definitions(ENSURE_MSYSTEM_IS_SET="MINGW64" MINGW_PREFIX="mingw64")
+	elseif(CMAKE_GENERATOR_PLATFORM STREQUAL "arm64")
+		add_compile_definitions(ENSURE_MSYSTEM_IS_SET="CLANGARM64" MINGW_PREFIX="clangarm64")
+	elseif(CMAKE_GENERATOR_PLATFORM STREQUAL "x86")
+		add_compile_definitions(ENSURE_MSYSTEM_IS_SET="MINGW32" MINGW_PREFIX="mingw32")
+	endif()
 	list(APPEND compat_SOURCES
 		compat/mingw.c
 		compat/winansi.c
diff --git a/environment.c b/environment.c
index 316e1e6f69a639..e2bffb3a340f55 100644
--- a/environment.c
+++ b/environment.c
@@ -91,31 +91,25 @@ int max_allowed_tree_depth =
 	 * the stack overflow can occur.
 	 */
 	512;
-#elif defined(GIT_WINDOWS_NATIVE) && defined(__clang__) && defined(__aarch64__)
+#elif defined(GIT_WINDOWS_NATIVE) && defined(__clang__)
 	/*
-	 * Similar to Visual C, it seems that on Windows/ARM64 the clang-based
-	 * builds have a smaller stack space available. When running out of
-	 * that stack space, a `STATUS_STACK_OVERFLOW` is produced. When the
+	 * Similar to Visual C, it seems that clang-based builds on Windows
+	 * have a smaller stack space available. When running out of that
+	 * stack space, a `STATUS_STACK_OVERFLOW` is produced. When the
 	 * Git command was run from an MSYS2 Bash, this unfortunately results
 	 * in an exit code 127. Let's prevent that by lowering the maximal
-	 * tree depth; This value seems to be low enough.
+	 * tree depth; Unfortunately, it seems that the exact limit differs
+	 * for aarch64 vs x86_64, and the difference is too large to simply
+	 * use a single limit.
 	 */
+#if defined(__aarch64__)
 	1280;
 #else
-#if defined(GIT_WINDOWS_NATIVE) && defined(__clang__) && defined(__aarch64__)
-	/*
-	 * Similar to Visual C, it seems that on Windows/ARM64 the clang-based
-	 * builds have a smaller stack space available. When running out of
-	 * that stack space, a `STATUS_STACK_OVERFLOW` is produced. When the
-	 * Git command was run from an MSYS2 Bash, this unfortunately results
-	 * in an exit code 127. Let's prevent that by lowering the maximal
-	 * tree depth; This value seems to be low enough.
-	 */
-	1280;
+	1152;
+#endif
 #else
 	2048;
 #endif
-#endif
 
 #ifndef PROTECT_HFS_DEFAULT
 #define PROTECT_HFS_DEFAULT 0
diff --git a/meson.build b/meson.build
index 46b1369c45e8ae..03fa16012dbefc 100644
--- a/meson.build
+++ b/meson.build
@@ -1271,7 +1271,6 @@ elif host_machine.system() == 'windows'
 
   libgit_c_args += [
     '-DDETECT_MSYS_TTY',
-    '-DENSURE_MSYSTEM_IS_SET',
     '-DNATIVE_CRLF',
     '-DNOGDI',
     '-DNO_POSIX_GOODIES',
@@ -1281,6 +1280,18 @@ elif host_machine.system() == 'windows'
     '-D__USE_MINGW_ANSI_STDIO=0',
   ]
 
+  msystem = get_option('msystem')
+  if msystem != ''
+    mingw_prefix = get_option('mingw_prefix')
+    if mingw_prefix == ''
+      mingw_prefix = '/' + msystem.to_lower()
+    endif
+    libgit_c_args += [
+      '-DENSURE_MSYSTEM_IS_SET="' + msystem + '"',
+      '-DMINGW_PREFIX="' + mingw_prefix + '"'
+    ]
+  endif
+
   libgit_dependencies += compiler.find_library('ntdll')
   libgit_include_directories += 'compat/win32'
   if compiler.get_id() == 'msvc'
diff --git a/meson_options.txt b/meson_options.txt
index e0be260ae1bce8..c2d9f0bfc0c2fb 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -21,6 +21,10 @@ option('runtime_prefix', type: 'boolean', value: false,
   description: 'Resolve ancillary tooling and support files relative to the location of the runtime binary instead of hard-coding them into the binary.')
 option('sane_tool_path', type: 'array', value: [],
   description: 'An array of paths to pick up tools from in case the normal tools are broken or lacking.')
+option('msystem', type: 'string', value: '',
+  description: 'Fall-back on Windows when MSYSTEM is not set.')
+option('mingw_prefix', type: 'string', value: '',
+  description: 'Fall-back on Windows when MINGW_PREFIX is not set.')
 
 # Build information compiled into Git and other parts like documentation.
 option('build_date', type: 'string', value: '',