diff --git a/core/compiler/test/intrinsics.factor b/core/compiler/test/intrinsics.factor
index 23e94a7974..d80b172c31 100644
--- a/core/compiler/test/intrinsics.factor
+++ b/core/compiler/test/intrinsics.factor
@@ -360,20 +360,25 @@ cell 8 = [
 [ 3 ] [ B{ 1 2 3 4 5 } 2 [ { simple-c-ptr fixnum } declare alien-unsigned-1 ] compile-1 ] unit-test
 
 [ ] [ B{ 1 2 3 4 5 } malloc-byte-array "b" set ] unit-test
+[ t ] [ "b" get >boolean ] unit-test
 
-[ 3 ] [ "b" get 2 [ alien-unsigned-1 ] compile-1 ] unit-test
-[ 3 ] [ "b" get [ { simple-alien } declare 2 alien-unsigned-1 ] compile-1 ] unit-test
-[ 3 ] [ "b" get 2 [ { simple-alien fixnum } declare alien-unsigned-1 ] compile-1 ] unit-test
-[ 3 ] [ "b" get 2 [ { simple-c-ptr fixnum } declare alien-unsigned-1 ] compile-1 ] unit-test
+"b" get [
+    [ 3 ] [ "b" get 2 [ alien-unsigned-1 ] compile-1 ] unit-test
+    [ 3 ] [ "b" get [ { simple-alien } declare 2 alien-unsigned-1 ] compile-1 ] unit-test
+    [ 3 ] [ "b" get 2 [ { simple-alien fixnum } declare alien-unsigned-1 ] compile-1 ] unit-test
+    [ 3 ] [ "b" get 2 [ { simple-c-ptr fixnum } declare alien-unsigned-1 ] compile-1 ] unit-test
 
-[ ] [ "b" get free ] unit-test
+    [ ] [ "b" get free ] unit-test
+] when
 
-[ ] [ "hello world" malloc-char-string "s" set ] unit-test
+[ t ] [ "hello world" malloc-char-string "s" set ] unit-test
 
-[ "hello world" ] [ "s" get <void*> [ { byte-array } declare *void* ] compile-1 alien>char-string ] unit-test
-[ "hello world" ] [ "s" get <void*> [ { simple-c-ptr } declare *void* ] compile-1 alien>char-string ] unit-test
+"s" get [
+    [ "hello world" ] [ "s" get <void*> [ { byte-array } declare *void* ] compile-1 alien>char-string ] unit-test
+    [ "hello world" ] [ "s" get <void*> [ { simple-c-ptr } declare *void* ] compile-1 alien>char-string ] unit-test
 
-[ ] [ "s" get free ] unit-test
+    [ ] [ "s" get free ] unit-test
+] when
 
 [ ALIEN: 1234 ] [ ALIEN: 1234 [ { simple-alien } declare <void*> ] compile-1 *void* ] unit-test
 [ ALIEN: 1234 ] [ ALIEN: 1234 [ { simple-c-ptr } declare <void*> ] compile-1 *void* ] unit-test
diff --git a/extra/io/windows/launcher/launcher.factor b/extra/io/windows/launcher/launcher.factor
index 98d241c8f6..f012f8d736 100644
--- a/extra/io/windows/launcher/launcher.factor
+++ b/extra/io/windows/launcher/launcher.factor
@@ -1,6 +1,7 @@
 USING: alien alien.c-types destructors io.windows libc
 io.nonblocking io.streams.duplex windows.types math
-windows.kernel32 windows namespaces io.launcher kernel ;
+windows.kernel32 windows namespaces io.launcher kernel
+io.windows.nt.backend ;
 IN: io.windows.launcher
 
 ! From MSDN: "Handles in PROCESS_INFORMATION must be closed with CloseHandle when they are no longer needed."
diff --git a/extra/io/windows/nt/backend/backend.factor b/extra/io/windows/nt/backend/backend.factor
index 06d508e757..5eac9d6751 100644
--- a/extra/io/windows/nt/backend/backend.factor
+++ b/extra/io/windows/nt/backend/backend.factor
@@ -1,9 +1,36 @@
 USING: alien alien.c-types arrays assocs combinators continuations
-destructors io io.backend io.nonblocking io.windows io.windows.nt libc
+destructors io io.backend io.nonblocking io.windows libc
 kernel math namespaces sequences threads tuples.lib windows
-windows.errors windows.kernel32 prettyprint ;
+windows.errors windows.kernel32 prettyprint strings splitting
+io.files windows.winsock ;
 IN: io.windows.nt.backend
 
+: unicode-prefix ( -- seq )
+    "\\\\?\\" ; inline
+
+M: windows-nt-io normalize-pathname ( string -- string )
+    dup string? [ "pathname must be a string" throw ] unless
+    "/" split "\\" join
+    {
+        ! empty
+        { [ dup empty? ] [ "empty path" throw ] }
+        ! .\\foo
+        { [ dup ".\\" head? ] [
+            >r unicode-prefix cwd r> 1 tail 3append
+        ] }
+        ! c:\\
+        { [ dup 1 tail ":" head? ] [ >r unicode-prefix r> append ] }
+        ! \\\\?\\c:\\foo
+        { [ dup unicode-prefix head? ] [ ] }
+        ! foo.txt ..\\foo.txt
+        { [ t ] [
+            [
+                unicode-prefix % cwd %
+                dup first CHAR: \\ = [ CHAR: \\ , ] unless %
+            ] "" make
+        ] }
+    } cond [ "/\\." member? ] rtrim ;
+
 SYMBOL: io-hash
 
 TUPLE: io-callback port continuation ;
@@ -63,9 +90,9 @@ C: <GetQueuedCompletionStatusParams> GetQueuedCompletionStatusParams
         GetQueuedCompletionStatus
     ] keep swap ;
 
-: lookup-callback ( GetQueuedCompletion-args -- callback ? )
+: lookup-callback ( GetQueuedCompletion-args -- callback )
     GetQueuedCompletionStatusParams-lpOverlapped* *void*
-    \ io-hash get-global delete-at* ;
+    \ io-hash get-global delete-at drop ;
 
 : wait-for-io ( timeout -- continuation/f )
     wait-for-overlapped
@@ -73,15 +100,18 @@ C: <GetQueuedCompletionStatusParams> GetQueuedCompletionStatusParams
         GetLastError dup (expected-io-error?) [
             2drop f
         ] [
-            (win32-error-string) swap lookup-callback [
+            dup ERROR_HANDLE_EOF = [
+                drop lookup-callback [
+                    io-callback-port t swap set-port-eof?
+                ] keep io-callback-continuation
+            ] [
+                (win32-error-string) swap lookup-callback
                 [ io-callback-port set-port-error ] keep
                 io-callback-continuation
-            ] [
-                drop "No callback found" 2array throw
             ] if
         ] if
     ] [
-        lookup-callback [ io-callback-continuation ] when
+        lookup-callback io-callback-continuation
     ] if ;
 
 : maybe-expire ( io-callbck -- )
@@ -99,3 +129,12 @@ M: windows-nt-io io-multiplex ( ms -- )
     cancel-timedout
     [ wait-for-io ] [ global [ "error: " write . flush ] bind drop f ] recover
     [ schedule-thread ] when* ;
+
+M: windows-nt-io init-io ( -- )
+    #! Should only be called on startup. Calling this at any
+    #! other time can have unintended consequences.
+    global [
+        master-completion-port \ master-completion-port set
+        H{ } clone \ io-hash set
+        init-winsock
+    ] bind ;
diff --git a/extra/io/windows/nt/nt.factor b/extra/io/windows/nt/nt.factor
index 5370580f10..7469410238 100644
--- a/extra/io/windows/nt/nt.factor
+++ b/extra/io/windows/nt/nt.factor
@@ -1,51 +1,10 @@
 ! Copyright (C) 2004, 2007 Mackenzie Straight, Doug Coleman.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: alien alien.c-types assocs byte-arrays combinators
-io.backend io.files io.nonblocking io.windows
-kernel libc math namespaces qualified sequences
-splitting strings threads windows windows.errors windows.winsock
-windows.kernel32 ;
-QUALIFIED: windows.winsock
-IN: io.windows.nt
-
-: unicode-prefix ( -- seq )
-    "\\\\?\\" ; inline
- 
-M: windows-nt-io normalize-pathname ( string -- string )
-    dup string? [ "pathname must be a string" throw ] unless
-    "/" split "\\" join
-    {
-        ! empty
-        { [ dup empty? ] [ "empty path" throw ] }
-        ! .\\foo
-        { [ dup ".\\" head? ] [
-            >r unicode-prefix cwd r> 1 tail 3append
-        ] }
-        ! c:\\
-        { [ dup 1 tail ":" head? ] [ >r unicode-prefix r> append ] }
-        ! \\\\?\\c:\\foo
-        { [ dup unicode-prefix head? ] [ ] }
-        ! foo.txt ..\\foo.txt
-        { [ t ] [
-            [
-                unicode-prefix % cwd %
-                dup first CHAR: \\ = [ CHAR: \\ , ] unless %
-            ] "" make
-        ] }
-    } cond [ "/\\." member? ] rtrim ;
-
+USE: io.windows
 USE: io.windows.nt.backend
 USE: io.windows.nt.files
 USE: io.windows.nt.sockets
+USE: io.backend
+USE: namespaces
 
 T{ windows-nt-io } io-backend set-global
-
-M: windows-nt-io init-io ( -- )
-    #! Should only be called on startup. Calling this at any
-    #! other time can have unintended consequences.
-    global [
-        master-completion-port \ master-completion-port set
-        H{ } clone \ io-hash set
-        init-winsock
-    ] bind ;
-
diff --git a/extra/windows/opengl32/opengl32.factor b/extra/windows/opengl32/opengl32.factor
index fcda38ca53..93473a4fd3 100644
--- a/extra/windows/opengl32/opengl32.factor
+++ b/extra/windows/opengl32/opengl32.factor
@@ -1,7 +1,8 @@
 ! Copyright (C) 2005, 2006 Doug Coleman.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: alien alien.c-types alien.syntax parser namespaces kernel
-math windows.types windows.types init assocs sequences opengl.gl ;
+math windows.types windows.types init assocs sequences opengl.gl
+libc ;
 IN: windows.opengl32
 
 ! PIXELFORMATDESCRIPTOR flags
diff --git a/misc/install.sh b/misc/install.sh
new file mode 100755
index 0000000000..10c0bfc0df
--- /dev/null
+++ b/misc/install.sh
@@ -0,0 +1,110 @@
+#!/bin/bash -e
+
+# Programs returning != 0 will not cause script to exit
+set +e
+
+# Case insensitive string comparison
+shopt -s nocaseglob
+shopt -s nocasematch
+
+ensure_program_installed() {
+        echo -n "Checking for $1..."
+        result=`type -p $1`
+        if ! [[ -n $result ]] ; then
+                echo "not found!"
+                echo "Install $1 and try again."
+                exit 1
+        fi
+        echo "found!"
+}
+
+check_ret() {
+        RET=$?
+        if [[ $RET -ne 0 ]] ; then
+                echo $1 failed
+                exit 5
+        fi
+}
+
+ensure_program_installed uname
+ensure_program_installed git
+ensure_program_installed wget
+ensure_program_installed gcc
+ensure_program_installed make
+
+GCC_VERSION=`gcc --version`
+if [[ $GCC_VERSION == *3.3.* ]] ; then
+        echo "You have a known buggy version of gcc (3.3)"
+        echo "Install gcc 3.4 or higher and try again."
+        exit 1
+fi
+
+# OS
+OS=
+uname_s=`uname -s`
+case $uname_s in
+        CYGWIN_NT-5.2-WOW64) OS=windows-nt;;
+        *CYGWIN_NT*) OS=windows-nt;;
+        *CYGWIN*) OS=windows-nt;;
+        *darwin*) OS=macosx;;
+        *linux*) OS=linux;;
+esac
+
+# Architecture
+ARCH=
+uname_m=`uname -m`
+case $uname_m in
+        i386) ARCH=x86;;
+        i686) ARCH=x86;;
+        *86) ARCH=x86;;
+        "Power Macintosh") ARCH=ppc;;
+esac
+
+WORD=
+C_WORD=factor-word-size
+# Word size
+echo "#include <stdio.h>" > $C_WORD.c
+echo "int main() { printf(\"%d\", 8*sizeof(long)); return 0; }" >> $C_WORD.c
+gcc -o $C_WORD $C_WORD.c
+WORD=$(./$C_WORD)
+check_ret $C_WORD
+rm -f $C_WORD*
+
+case $OS in
+        windows-nt) FACTOR_BINARY=factor-nt;;
+        macosx) FACTOR_BINARY=./Factor.app/Contents/MacOS/factor;;
+        *) FACTOR_BINARY=factor;;
+esac
+
+MAKE_TARGET=$OS-$ARCH-$WORD
+BOOT_IMAGE=boot.$ARCH.$WORD.image
+
+echo OS=$OS
+echo ARCH=$ARCH
+echo WORD=$WORD
+echo FACTOR_BINARY=$FACTOR_BINARY
+echo MAKE_TARGET=$MAKE_TARGET
+echo BOOT_IMAGE=$BOOT_IMAGE
+
+if ! [[ -n $OS && -n $ARCH && -n $WORD ]] ; then
+        echo "OS, ARCH, or WORD is empty.  Please report this"
+        exit 4
+fi
+
+echo "Downloading the git repository from factorcode.org..."
+git clone git://factorcode.org/git/factor.git
+check_ret git
+
+cd factor
+check_ret cd
+
+make $MAKE_TARGET
+check_ret make
+
+echo "Deleting old images..."
+rm $BOOT_IMAGE > /dev/null 2>&1
+rm $BOOT_IMAGE.* > /dev/null 2>&1
+wget http://factorcode.org/images/latest/$BOOT_IMAGE
+check_ret wget
+
+./$FACTOR_BINARY -i=$BOOT_IMAGE
diff --git a/vm/cpu-ppc.h b/vm/cpu-ppc.h
index c74e13e68b..ac4a0a92ee 100644
--- a/vm/cpu-ppc.h
+++ b/vm/cpu-ppc.h
@@ -1,5 +1,5 @@
 #define FACTOR_CPU_STRING "ppc"
-#define FASTCALL
+#define F_FASTCALL
 
 register CELL ds asm("r14");
 register CELL rs asm("r15");
diff --git a/vm/cpu-x86.32.h b/vm/cpu-x86.32.h
index 4c4acb0ad3..a81c9987c4 100644
--- a/vm/cpu-x86.32.h
+++ b/vm/cpu-x86.32.h
@@ -3,4 +3,5 @@
 register CELL ds asm("esi");
 register CELL rs asm("edi");
 
-#define FASTCALL __attribute__ ((regparm (2)))
+#define F_FASTCALL __attribute__ ((regparm (2)))
+
diff --git a/vm/cpu-x86.64.h b/vm/cpu-x86.64.h
index 0b3b5a2471..6412355129 100644
--- a/vm/cpu-x86.64.h
+++ b/vm/cpu-x86.64.h
@@ -3,4 +3,4 @@
 register CELL ds asm("r14");
 register CELL rs asm("r15");
 
-#define FASTCALL
+#define F_FASTCALL
diff --git a/vm/cpu-x86.S b/vm/cpu-x86.S
index ec5d09291e..7032b77e18 100644
--- a/vm/cpu-x86.S
+++ b/vm/cpu-x86.S
@@ -2,7 +2,7 @@
 	mov QUOT_XT_OFFSET(ARG0),XT_REG ;     /* Load quot-xt */ \
 	jmp *XT_REG                           /* Jump to quot-xt */
 
-DEF(FASTCALL void,c_to_factor,(CELL quot)):
+DEF(F_FASTCALL void,c_to_factor,(CELL quot)):
 	PUSH_NONVOLATILE
 	push ARG0                             /* Save quot */
 
@@ -17,38 +17,38 @@ DEF(FASTCALL void,c_to_factor,(CELL quot)):
 	POP_NONVOLATILE
 	ret
 
-DEF(FASTCALL void,undefined,(CELL word)):
+DEF(F_FASTCALL void,undefined,(CELL word)):
 	mov STACK_REG,ARG1                    /* Pass callstack pointer */
 	jmp MANGLE(undefined_error)           /* This throws an error */
 
-DEF(FASTCALL void,dosym,(CELL word)):
+DEF(F_FASTCALL void,dosym,(CELL word)):
 	add $CELL_SIZE,DS_REG                 /* Increment stack pointer */
 	mov ARG0,(DS_REG)                     /* Store word on stack */
 	ret
 
 /* Here we have two entry points. The first one is taken when profiling is
 enabled */
-DEF(FASTCALL void,docol_profiling,(CELL word)):
+DEF(F_FASTCALL void,docol_profiling,(CELL word)):
 	add $CELL_SIZE,PROFILING_OFFSET(ARG0) /* Increment profile-count slot */
-DEF(FASTCALL void,docol,(CELL word)):
+DEF(F_FASTCALL void,docol,(CELL word)):
 	mov WORD_DEF_OFFSET(ARG0),ARG0        /* Load word-def slot */
 	JUMP_QUOT
 
 /* We must pass the XT to the quotation in ECX. */
-DEF(FASTCALL void,primitive_call,(void)):
+DEF(F_FASTCALL void,primitive_call,(void)):
         mov (DS_REG),ARG0                     /* Load quotation from data stack */
 	sub $CELL_SIZE,DS_REG                 /* Pop data stack */
 	JUMP_QUOT
 
 /* We pass the word in EAX and the XT in ECX. Don't mess up EDX, it's the
 callstack top parameter to primitives. */
-DEF(FASTCALL void,primitive_execute,(void)):
+DEF(F_FASTCALL void,primitive_execute,(void)):
 	mov (DS_REG),ARG0                     /* Load word from data stack */
 	sub $CELL_SIZE,DS_REG                 /* Pop data stack */
         mov WORD_XT_OFFSET(ARG0),XT_REG       /* Load word-xt slot */
 	jmp *XT_REG                           /* Go */
 
-DEF(FASTCALL void,throw_impl,(CELL quot, F_STACK_FRAME *rewind_to)):
+DEF(F_FASTCALL void,throw_impl,(CELL quot, F_STACK_FRAME *rewind_to)):
 	mov ARG1,STACK_REG                    /* rewind_to */
 	JUMP_QUOT
 
diff --git a/vm/cpu-x86.h b/vm/cpu-x86.h
index 63bf2b08e1..91f1f8236a 100644
--- a/vm/cpu-x86.h
+++ b/vm/cpu-x86.h
@@ -22,12 +22,12 @@ typedef struct _F_STACK_FRAME
 
 INLINE void flush_icache(CELL start, CELL len) {}
 
-FASTCALL void c_to_factor(CELL quot);
-FASTCALL void throw_impl(CELL quot, F_STACK_FRAME *rewind_to);
-FASTCALL void undefined(CELL word);
-FASTCALL void dosym(CELL word);
-FASTCALL void docol_profiling(CELL word);
-FASTCALL void docol(CELL word);
-FASTCALL void lazy_jit_compile(CELL quot);
+F_FASTCALL void c_to_factor(CELL quot);
+F_FASTCALL void throw_impl(CELL quot, F_STACK_FRAME *rewind_to);
+F_FASTCALL void undefined(CELL word);
+F_FASTCALL void dosym(CELL word);
+F_FASTCALL void docol_profiling(CELL word);
+F_FASTCALL void docol(CELL word);
+F_FASTCALL void lazy_jit_compile(CELL quot);
 
 void set_callstack(F_STACK_FRAME *to, F_STACK_FRAME *from, CELL length, void *memcpy);
diff --git a/vm/jit.c b/vm/jit.c
index 6faf0a6a17..51fa06ef86 100644
--- a/vm/jit.c
+++ b/vm/jit.c
@@ -34,7 +34,7 @@ bool jit_stack_frame_p(F_ARRAY *array)
 	return false;
 }
 
-FASTCALL CELL jit_compile(CELL tagged, F_STACK_FRAME *stack)
+F_FASTCALL CELL jit_compile(CELL tagged, F_STACK_FRAME *stack)
 {
 	stack_chain->callstack_top = stack;
 
diff --git a/vm/jit.h b/vm/jit.h
index a9f1399472..d1c91b631b 100644
--- a/vm/jit.h
+++ b/vm/jit.h
@@ -1,2 +1,2 @@
-DLLEXPORT FASTCALL CELL jit_compile(CELL tagged, F_STACK_FRAME *stack);
+DLLEXPORT F_FASTCALL CELL jit_compile(CELL tagged, F_STACK_FRAME *stack);
 XT quot_offset_to_pc(F_QUOTATION *quot, F_FIXNUM offset);
diff --git a/vm/os-unix.c b/vm/os-unix.c
index 2d9ba02ca5..65ae79550c 100644
--- a/vm/os-unix.c
+++ b/vm/os-unix.c
@@ -179,11 +179,6 @@ INLINE F_STACK_FRAME *uap_stack_pointer(void *uap)
 		return NULL;
 }
 
-void memory_signal_handler_impl(void)
-{
-	memory_protection_error(signal_fault_addr,signal_callstack_top);
-}
-
 void memory_signal_handler(int signal, siginfo_t *siginfo, void *uap)
 {
 	signal_fault_addr = (CELL)siginfo->si_addr;
@@ -191,11 +186,6 @@ void memory_signal_handler(int signal, siginfo_t *siginfo, void *uap)
 	UAP_PROGRAM_COUNTER(uap) = (CELL)memory_signal_handler_impl;
 }
 
-void misc_signal_handler_impl(void)
-{
-	signal_error(signal_number,signal_callstack_top);
-}
-
 void misc_signal_handler(int signal, siginfo_t *siginfo, void *uap)
 {
 	signal_number = signal;
diff --git a/vm/os-windows-nt.c b/vm/os-windows-nt.c
index 2a87a85223..8f7513a32a 100644
--- a/vm/os-windows-nt.c
+++ b/vm/os-windows-nt.c
@@ -23,31 +23,39 @@ DEFINE_PRIMITIVE(cd)
 	SetCurrentDirectory(unbox_u16_string());
 }
 
-void seh_call(void (*func)(), exception_handler_t *handler)
+long exception_handler(PEXCEPTION_POINTERS pe)
 {
-	exception_record_t record;
-	asm volatile("mov %%fs:0, %0" : "=r" (record.next_handler));
-	asm volatile("mov %0, %%fs:0" : : "r" (&record));
-	record.handler_func = handler;
-	func();
-	asm volatile("mov %0, %%fs:0" : "=r" (record.next_handler));
-}
+	PEXCEPTION_RECORD e = (PEXCEPTION_RECORD)pe->ExceptionRecord;
+	CONTEXT *c = (CONTEXT*)pe->ContextRecord;
 
-long exception_handler(PEXCEPTION_RECORD rec, void *frame, void *ctx, void *dispatch)
-{
-	if(rec->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
-		memory_protection_error(
-			rec->ExceptionInformation[1],
-			native_stack_pointer());
-	else if(rec->ExceptionCode == EXCEPTION_FLT_DIVIDE_BY_ZERO
-			|| rec->ExceptionCode == EXCEPTION_INT_DIVIDE_BY_ZERO)
-		general_error(ERROR_DIVIDE_BY_ZERO,F,F,false,(void*)rec->ExceptionInformation[1]);
+	if(in_code_heap_p(c->Eip))
+		signal_callstack_top = (void*)c->Esp;
 	else
-		signal_error(11,(void*)rec->ExceptionInformation[1]);
-	return -1; /* unreachable */
+		signal_callstack_top = NULL;
+
+	if(e->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
+	{
+		signal_fault_addr = e->ExceptionInformation[1];
+		c->Eip = (CELL)memory_signal_handler_impl;
+	}
+	else if(e->ExceptionCode == EXCEPTION_FLT_DIVIDE_BY_ZERO
+			|| e->ExceptionCode == EXCEPTION_INT_DIVIDE_BY_ZERO)
+	{
+		signal_number = ERROR_DIVIDE_BY_ZERO;
+		c->Eip = (CELL)divide_by_zero_signal_handler_impl;
+	}
+	else
+	{
+		signal_number = 11;
+		c->Eip = (CELL)misc_signal_handler_impl;
+	}
+
+	return EXCEPTION_CONTINUE_EXECUTION;
 }
 
-void run_toplevel(void)
+void c_to_factor_toplevel(CELL quot)
 {
-	seh_call(run, exception_handler);
+	AddVectoredExceptionHandler(0, (void*)exception_handler);
+	c_to_factor(quot);
+	RemoveVectoredExceptionHandler((void*)exception_handler);
 }
diff --git a/vm/os-windows-nt.h b/vm/os-windows-nt.h
index 514da31477..f3017b0cbe 100644
--- a/vm/os-windows-nt.h
+++ b/vm/os-windows-nt.h
@@ -1,3 +1,6 @@
+#undef _WIN32_WINNT
+#define _WIN32_WINNT 0x0501  // For AddVectoredExceptionHandler
+
 #ifndef UNICODE
 #define UNICODE
 #endif
@@ -10,3 +13,13 @@ typedef char F_SYMBOL;
 #define FACTOR_OS_STRING "windows"
 #define FACTOR_DLL L"factor-nt.dll"
 #define FACTOR_DLL_NAME "factor-nt.dll"
+
+void c_to_factor_toplevel(CELL quot);
+
+CELL signal_number;
+CELL signal_fault_addr;
+void *signal_callstack_top;
+
+void memory_signal_handler_impl(void);
+void divide_by_zero_signal_handler_impl(void);
+void misc_signal_handler_impl(void);
diff --git a/vm/os-windows.c b/vm/os-windows.c
index 823fd7e9d0..1be3e2a2af 100644
--- a/vm/os-windows.c
+++ b/vm/os-windows.c
@@ -51,8 +51,8 @@ void ffi_dlopen (F_DLL *dll, bool error)
 	{
 		dll->dll = NULL;
 		if(error)
-			general_error(ERROR_FFI,F,
-				tag_object(get_error_message()));
+			general_error(ERROR_FFI,F,F,
+				(void*)tag_object(get_error_message()));
 		else
 			return;
 	}
@@ -204,9 +204,3 @@ void sleep_millis(DWORD msec)
 {
     Sleep(msec);
 }
-
-void run(void)
-{
-	interpreter();
-}
-
diff --git a/vm/os-windows.h b/vm/os-windows.h
index 04f5c87ac7..ed9b87aa93 100644
--- a/vm/os-windows.h
+++ b/vm/os-windows.h
@@ -49,20 +49,5 @@ s64 current_millis(void);
 
 INLINE void reset_stdio(void) {}
 
-/* SEH support. Proceed with caution. */
-typedef long exception_handler_t(
-	PEXCEPTION_RECORD rec, void *frame, void *context, void *dispatch);
+long exception_handler(PEXCEPTION_POINTERS pe);
 
-typedef struct exception_record
-{
-	struct exception_record *next_handler;
-	void *handler_func;
-} exception_record_t;
-
-long exception_handler(PEXCEPTION_RECORD rec, void *frame, void *ctx, void *dispatch);
-
-DECLARE_PRIMITIVE(open_file);
-DECLARE_PRIMITIVE(stat);
-DECLARE_PRIMITIVE(read_dir);
-DECLARE_PRIMITIVE(cwd);
-DECLARE_PRIMITIVE(cd);
diff --git a/vm/primitives.h b/vm/primitives.h
index ce22cff528..2c0040f13f 100644
--- a/vm/primitives.h
+++ b/vm/primitives.h
@@ -14,19 +14,19 @@ DEFINE_PRIMITIVE(name)
 
 Becomes
 
-FASTCALL void primitive_name(CELL word, F_STACK_FRAME *callstack_top)
+F_FASTCALL void primitive_name(CELL word, F_STACK_FRAME *callstack_top)
 {
 	stack_chain->callstack_top = callstack_top;
 	... CODE ...
 }
 
-On x86, FASTCALL expands into a GCC declaration which forces the two parameters
-to be passed in registers. This simplifies the quotation compiler and support
-code in cpu-x86.S. */
+On x86, F_FASTCALL expands into a GCC declaration which forces the two
+parameters to be passed in registers. This simplifies the quotation compiler
+and support code in cpu-x86.S. */
 #define DEFINE_PRIMITIVE(name) \
 	INLINE void primitive_##name##_impl(void); \
 	\
-	FASTCALL void primitive_##name(CELL word, F_STACK_FRAME *callstack_top) \
+	F_FASTCALL void primitive_##name(CELL word, F_STACK_FRAME *callstack_top) \
 	{ \
 		stack_chain->callstack_top = callstack_top; \
 		primitive_##name##_impl(); \
@@ -36,4 +36,4 @@ code in cpu-x86.S. */
 
 /* Prototype for header files */
 #define DECLARE_PRIMITIVE(name) \
-	FASTCALL void primitive_##name(CELL word, F_STACK_FRAME *callstack_top)
+	F_FASTCALL void primitive_##name(CELL word, F_STACK_FRAME *callstack_top)
diff --git a/vm/run.c b/vm/run.c
index 255be845d3..d4f95a47f2 100644
--- a/vm/run.c
+++ b/vm/run.c
@@ -197,7 +197,7 @@ void not_implemented_error(void)
 }
 
 /* This function is called from the undefined function in cpu_*.S */
-FASTCALL void undefined_error(CELL word, F_STACK_FRAME *callstack_top)
+F_FASTCALL void undefined_error(CELL word, F_STACK_FRAME *callstack_top)
 {
 	stack_chain->callstack_top = callstack_top;
 	general_error(ERROR_UNDEFINED_WORD,word,F,NULL);
@@ -244,6 +244,21 @@ void divide_by_zero_error(F_STACK_FRAME *native_stack)
 	general_error(ERROR_DIVIDE_BY_ZERO,F,F,native_stack);
 }
 
+void memory_signal_handler_impl(void)
+{
+    memory_protection_error(signal_fault_addr,signal_callstack_top);
+}
+
+void divide_by_zero_signal_handler_impl(void)
+{
+    divide_by_zero_error(signal_callstack_top);
+}
+
+void misc_signal_handler_impl(void)
+{
+    signal_error(signal_number,signal_callstack_top);
+}
+
 DEFINE_PRIMITIVE(throw)
 {
 	uncurry(dpop());
diff --git a/vm/run.h b/vm/run.h
index 72ee7eea17..73454989ce 100644
--- a/vm/run.h
+++ b/vm/run.h
@@ -197,7 +197,7 @@ void signal_error(int signal, F_STACK_FRAME *native_stack);
 void type_error(CELL type, CELL tagged);
 void not_implemented_error(void);
 
-FASTCALL void undefined_error(CELL word, F_STACK_FRAME *callstack_top);
+F_FASTCALL void undefined_error(CELL word, F_STACK_FRAME *callstack_top);
 
 DECLARE_PRIMITIVE(throw);
 
diff --git a/vm/stack.c b/vm/stack.c
index b2a05b9181..9ba4e35bf5 100644
--- a/vm/stack.c
+++ b/vm/stack.c
@@ -19,7 +19,7 @@ void fix_stacks(void)
 }
 
 /* called before entry into Factor code. */
-FASTCALL void save_callstack_bottom(F_STACK_FRAME *callstack_bottom)
+F_FASTCALL void save_callstack_bottom(F_STACK_FRAME *callstack_bottom)
 {
 	stack_chain->callstack_bottom = callstack_bottom;
 }
diff --git a/vm/stack.h b/vm/stack.h
index 62ee1d9ba2..58be5ae52f 100644
--- a/vm/stack.h
+++ b/vm/stack.h
@@ -48,7 +48,7 @@ CELL ds_size, rs_size;
 void reset_datastack(void);
 void reset_retainstack(void);
 void fix_stacks(void);
-FASTCALL void save_callstack_bottom(F_STACK_FRAME *callstack_bottom);
+F_FASTCALL void save_callstack_bottom(F_STACK_FRAME *callstack_bottom);
 DLLEXPORT void save_stacks(void);
 DLLEXPORT void nest_stacks(void);
 DLLEXPORT void unnest_stacks(void);