diff --git a/spim/include/u.h b/spim/include/u.h
new file mode 100644
index 000000000..c30ebd882
--- /dev/null
+++ b/spim/include/u.h
@@ -0,0 +1,66 @@
+#define nil		((void*)0)
+typedef	unsigned short	ushort;
+typedef	unsigned char	uchar;
+typedef	unsigned long	ulong;
+typedef	unsigned int	uint;
+typedef	signed char	schar;
+typedef	long long	vlong;
+typedef	unsigned long long uvlong;
+typedef unsigned long	uintptr;
+typedef unsigned long	usize;
+typedef	uint		Rune;
+typedef 	union FPdbleword FPdbleword;
+typedef long	jmp_buf[2];
+#define	JMPBUFSP	0
+#define	JMPBUFPC	1
+#define	JMPBUFDPC	0
+typedef unsigned int	mpdigit;	/* for /sys/include/mp.h */
+typedef unsigned char u8int;
+typedef unsigned short u16int;
+typedef unsigned int	u32int;
+typedef unsigned long long u64int;
+
+/* FCR */
+#define	FPINEX	(1<<7)
+#define	FPUNFL	(1<<8)
+#define	FPOVFL	(1<<9)
+#define	FPZDIV	(1<<10)
+#define	FPINVAL	(1<<11)
+#define	FPRNR	(0<<0)
+#define	FPRZ	(1<<0)
+#define	FPRPINF	(2<<0)
+#define	FPRNINF	(3<<0)
+#define	FPRMASK	(3<<0)
+#define	FPPEXT	0
+#define	FPPSGL	0
+#define	FPPDBL	0
+#define	FPPMASK	0
+/* FSR */
+#define	FPAINEX	(1<<2)
+#define	FPAOVFL	(1<<4)
+#define	FPAUNFL	(1<<3)
+#define	FPAZDIV	(1<<5)
+#define	FPAINVAL	(1<<6)
+union FPdbleword
+{
+	double	x;
+	struct {	/* big endian */
+		ulong hi;
+		ulong lo;
+	};
+};
+
+/* stdarg */
+typedef	char*	va_list;
+#define va_start(list, start) list =\
+	(sizeof(start) < 4?\
+		(char*)((int*)&(start)+1):\
+		(char*)(&(start)+1))
+#define va_end(list)\
+	USED(list)
+#define va_arg(list, mode)\
+	((sizeof(mode) == 1)?\
+		((list += 4), (mode*)list)[-1]:\
+	(sizeof(mode) == 2)?\
+		((list += 4), (mode*)list)[-1]:\
+		((list += sizeof(mode)), (mode*)list)[-1])
diff --git a/spim/include/ureg.h b/spim/include/ureg.h
new file mode 100644
index 000000000..32cbfb3fc
--- /dev/null
+++ b/spim/include/ureg.h
@@ -0,0 +1,44 @@
+struct Ureg
+{
+	ulong	status;
+	ulong	pc;
+	union{
+		ulong	sp;		/* r29 */
+		ulong	usp;		/* r29 */
+	};
+	ulong	cause;
+	ulong	badvaddr;
+	ulong	tlbvirt;
+	ulong	hi;
+	ulong	lo;
+	ulong	r31;
+	ulong	r30;
+	ulong	r28;
+	ulong	r27;		/* unused */
+	ulong	r26;		/* unused */
+	ulong	r25;
+	ulong	r24;
+	ulong	r23;
+	ulong	r22;
+	ulong	r21;
+	ulong	r20;
+	ulong	r19;
+	ulong	r18;
+	ulong	r17;
+	ulong	r16;
+	ulong	r15;
+	ulong	r14;
+	ulong	r13;
+	ulong	r12;
+	ulong	r11;
+	ulong	r10;
+	ulong	r9;
+	ulong	r8;
+	ulong	r7;
+	ulong	r6;
+	ulong	r5;
+	ulong	r4;
+	ulong	r3;
+	ulong	r2;
+	ulong	r1;
+};
diff --git a/spim/mkfile b/spim/mkfile
new file mode 100644
index 000000000..7d76319c0
--- /dev/null
+++ b/spim/mkfile
@@ -0,0 +1,6 @@
+</sys/src/mkfile.proto
+
+CC=0c
+LD=0l
+O=0
+AS=0a