diff --git a/build.sh b/build.sh
index 90ace80..05085a2 100755
--- a/build.sh
+++ b/build.sh
@@ -19,6 +19,7 @@ then
 	clang-format -i src/uxn.c
 	clang-format -i src/uxn.h
 	clang-format -i src/uxn11.c
+	clang-format -i src/uxnasm.c
 	clang-format -i src/uxncli.c
 	clang-format -i src/devices/*
 fi
@@ -28,13 +29,15 @@ rm -f bin/*
 mkdir -p bin
 
 echo "Building.."
+cc -DNDEBUG -Os -g0 -s src/uxnasm.c -o bin/uxnasm
 if [ "${1}" = '--install' ];
 then
 	echo "Installing.."
 	gcc ${RELEASE_FLAGS} ${EMU_INC}
 	gcc ${RELEASE_FLAGS} ${CLI_INC}
-	cp bin/uxn11 ~/bin
+	cp bin/uxnasm ~/bin
 	cp bin/uxncli ~/bin
+	cp bin/uxn11 ~/bin
 else
 	gcc ${DEBUG_FLAGS} ${EMU_INC}
 	gcc ${DEBUG_FLAGS} ${CLI_INC} 
diff --git a/src/uxnasm.c b/src/uxnasm.c
new file mode 100644
index 0000000..03cc333
--- /dev/null
+++ b/src/uxnasm.c
@@ -0,0 +1,471 @@
+#include <stdio.h>
+
+/*
+Copyright (c) 2021 Devine Lu Linvega
+
+Permission to use, copy, modify, and distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE.
+*/
+
+#define TRIM 0x0100
+#define LENGTH 0x10000
+
+typedef unsigned char Uint8;
+typedef signed char Sint8;
+typedef unsigned short Uint16;
+
+typedef struct {
+	char name[0x40], items[0x40][0x40];
+	Uint8 len;
+} Macro;
+
+typedef struct {
+	char name[0x40];
+	Uint16 addr, refs;
+} Label;
+
+typedef struct {
+	char name[0x40], rune;
+	Uint16 addr;
+} Reference;
+
+typedef struct {
+	Uint8 data[LENGTH];
+	unsigned int ptr, length;
+	Uint16 llen, mlen, rlen;
+	Label labels[0x400];
+	Macro macros[0x100];
+	Reference refs[0x800];
+	char scope[0x40];
+} Program;
+
+Program p;
+static int litlast = 0;
+static int jsrlast = 0;
+
+/* clang-format off */
+
+static char ops[][4] = {
+	"LIT", "INC", "POP", "NIP", "SWP", "ROT", "DUP", "OVR",
+	"EQU", "NEQ", "GTH", "LTH", "JMP", "JCN", "JSR", "STH",
+	"LDZ", "STZ", "LDR", "STR", "LDA", "STA", "DEI", "DEO",
+	"ADD", "SUB", "MUL", "DIV", "AND", "ORA", "EOR", "SFT"
+};
+
+static int   scmp(char *a, char *b, int len) { int i = 0; while(a[i] == b[i]) if(!a[i] || ++i >= len) return 1; return 0; } /* string compare */
+static int   sihx(char *s) { int i = 0; char c; while((c = s[i++])) if(!(c >= '0' && c <= '9') && !(c >= 'a' && c <= 'f')) return 0; return i > 1; } /* string is hexadecimal */
+static int   shex(char *s) { int n = 0, i = 0; char c; while((c = s[i++])) if(c >= '0' && c <= '9') n = n * 16 + (c - '0'); else if(c >= 'a' && c <= 'f') n = n * 16 + 10 + (c - 'a'); return n; } /* string to num */
+static int   slen(char *s) { int i = 0; while(s[i]) i++; return i; } /* string length */
+static int   spos(char *s, char c) { Uint8 i = 0, j; while((j = s[i++])) if(j == c) return i; return -1; } /* character position */
+static char *scpy(char *src, char *dst, int len) { int i = 0; while((dst[i] = src[i]) && i < len - 2) i++; dst[i + 1] = '\0'; return dst; } /* string copy */
+static char *scat(char *dst, const char *src) { char *ptr = dst + slen(dst); while(*src) *ptr++ = *src++; *ptr = '\0'; return dst; } /* string cat */
+
+/* clang-format on */
+
+static int parse(char *w, FILE *f);
+
+static int
+error(const char *name, const char *msg)
+{
+	fprintf(stderr, "%s: %s\n", name, msg);
+	return 0;
+}
+
+static char *
+sublabel(char *src, char *scope, char *name)
+{
+	return scat(scat(scpy(scope, src, 0x40), "/"), name);
+}
+
+static Macro *
+findmacro(char *name)
+{
+	int i;
+	for(i = 0; i < p.mlen; i++)
+		if(scmp(p.macros[i].name, name, 0x40))
+			return &p.macros[i];
+	return NULL;
+}
+
+static Label *
+findlabel(char *name)
+{
+	int i;
+	for(i = 0; i < p.llen; i++)
+		if(scmp(p.labels[i].name, name, 0x40))
+			return &p.labels[i];
+	return NULL;
+}
+
+static Uint8
+findopcode(char *s)
+{
+	int i;
+	for(i = 0; i < 0x20; i++) {
+		int m = 0;
+		if(!scmp(ops[i], s, 3))
+			continue;
+		if(!i) i |= (1 << 7); /* force keep for LIT */
+		while(s[3 + m]) {
+			if(s[3 + m] == '2')
+				i |= (1 << 5); /* mode: short */
+			else if(s[3 + m] == 'r')
+				i |= (1 << 6); /* mode: return */
+			else if(s[3 + m] == 'k')
+				i |= (1 << 7); /* mode: keep */
+			else
+				return 0; /* failed to match */
+			m++;
+		}
+		return i;
+	}
+	return 0;
+}
+
+static int
+makemacro(char *name, FILE *f)
+{
+	Macro *m;
+	char word[0x40];
+	if(findmacro(name))
+		return error("Macro duplicate", name);
+	if(sihx(name) && slen(name) % 2 == 0)
+		return error("Macro name is hex number", name);
+	if(findopcode(name) || scmp(name, "BRK", 4) || !slen(name))
+		return error("Macro name is invalid", name);
+	if(p.mlen == 0x100)
+		return error("Macros limit exceeded", name);
+	m = &p.macros[p.mlen++];
+	scpy(name, m->name, 0x40);
+	while(fscanf(f, "%63s", word) == 1) {
+		if(word[0] == '{') continue;
+		if(word[0] == '}') break;
+		if(word[0] == '%')
+			return error("Macro error", name);
+		if(m->len >= 0x40)
+			return error("Macro size exceeded", name);
+		scpy(word, m->items[m->len++], 0x40);
+	}
+	return 1;
+}
+
+static int
+makelabel(char *name)
+{
+	Label *l;
+	if(findlabel(name))
+		return error("Label duplicate", name);
+	if(sihx(name) && (slen(name) == 2 || slen(name) == 4))
+		return error("Label name is hex number", name);
+	if(findopcode(name) || scmp(name, "BRK", 4) || !slen(name))
+		return error("Label name is invalid", name);
+	if(p.llen == 0x400)
+		return error("Labels limit exceeded", name);
+	l = &p.labels[p.llen++];
+	l->addr = p.ptr;
+	l->refs = 0;
+	scpy(name, l->name, 0x40);
+	return 1;
+}
+
+static int
+makereference(char *scope, char *label, Uint16 addr)
+{
+	char subw[0x40], parent[0x40];
+	Reference *r;
+	if(p.rlen == 0x800)
+		return error("References limit exceeded", label);
+	r = &p.refs[p.rlen++];
+	if(label[1] == '&')
+		scpy(sublabel(subw, scope, label + 2), r->name, 0x40);
+	else {
+		int pos = spos(label + 1, '/');
+		if(pos > 0) {
+			Label *l;
+			if((l = findlabel(scpy(label + 1, parent, pos))))
+				l->refs++;
+		}
+		scpy(label + 1, r->name, 0x40);
+	}
+	r->rune = label[0];
+	r->addr = addr;
+	return 1;
+}
+
+static int
+writebyte(Uint8 b)
+{
+	if(p.ptr < TRIM)
+		return error("Writing in zero-page", "");
+	else if(p.ptr > 0xffff)
+		return error("Writing after the end of RAM", "");
+	else if(p.ptr < p.length)
+		return error("Memory overwrite", "");
+	p.data[p.ptr++] = b;
+	p.length = p.ptr;
+	litlast = 0;
+	jsrlast = 0;
+	return 1;
+}
+
+static int
+writeopcode(char *w)
+{
+	Uint8 res;
+	if(jsrlast && scmp(w, "JMP2r", 5)) { /* tail-call optimization */
+		p.data[p.ptr - 1] = jsrlast == 2 ? findopcode("JMP2") : findopcode("JMP");
+		jsrlast = 0;
+		return 1;
+	}
+	res = writebyte(findopcode(w));
+	if(scmp(w, "JSR2", 4))
+		jsrlast = 2;
+	else if(scmp(w, "JSR", 3))
+		jsrlast = 1;
+	return res;
+}
+
+static int
+writeshort(Uint16 s, int lit)
+{
+	if(lit)
+		if(!writebyte(findopcode("LIT2"))) return 0;
+	return writebyte(s >> 8) && writebyte(s & 0xff);
+}
+
+static int
+writelitbyte(Uint8 b)
+{
+	if(litlast) { /* literals optimization */
+		Uint8 hb = p.data[p.ptr - 1];
+		p.ptr -= 2;
+		p.length = p.ptr;
+		return writeshort((hb << 8) + b, 1);
+	}
+	if(!writebyte(findopcode("LIT"))) return 0;
+	if(!writebyte(b)) return 0;
+	litlast = 1;
+	return 1;
+}
+
+static int
+doinclude(const char *filename)
+{
+	FILE *f;
+	char w[0x40];
+	if(!(f = fopen(filename, "r")))
+		return error("Include missing", filename);
+	while(fscanf(f, "%63s", w) == 1)
+		if(!parse(w, f))
+			return error("Unknown token", w);
+	fclose(f);
+	return 1;
+}
+
+static int
+parse(char *w, FILE *f)
+{
+	int i;
+	char word[0x40], subw[0x40], c;
+	Macro *m;
+	if(slen(w) >= 63)
+		return error("Invalid token", w);
+	switch(w[0]) {
+	case '(': /* comment */
+		if(slen(w) != 1) fprintf(stderr, "-- Malformed comment: %s\n", w);
+		i = 1; /* track nested comment depth */
+		while(fscanf(f, "%63s", word) == 1) {
+			if(slen(word) != 1)
+				continue;
+			else if(word[0] == '(')
+				i++;
+			else if(word[0] == ')' && --i < 1)
+				break;
+		}
+		break;
+	case '~': /* include */
+		if(!doinclude(w + 1))
+			return error("Invalid include", w);
+		break;
+	case '%': /* macro */
+		if(!makemacro(w + 1, f))
+			return error("Invalid macro", w);
+		break;
+	case '|': /* pad-absolute */
+		if(!sihx(w + 1))
+			return error("Invalid padding", w);
+		p.ptr = shex(w + 1);
+		litlast = jsrlast = 0;
+		break;
+	case '$': /* pad-relative */
+		if(!sihx(w + 1))
+			return error("Invalid padding", w);
+		p.ptr += shex(w + 1);
+		litlast = jsrlast = 0;
+		break;
+	case '@': /* label */
+		if(!makelabel(w + 1))
+			return error("Invalid label", w);
+		scpy(w + 1, p.scope, 0x40);
+		litlast = jsrlast = 0;
+		break;
+	case '&': /* sublabel */
+		if(!makelabel(sublabel(subw, p.scope, w + 1)))
+			return error("Invalid sublabel", w);
+		litlast = jsrlast = 0;
+		break;
+	case '#': /* literals hex */
+		if(!sihx(w + 1) || (slen(w) != 3 && slen(w) != 5))
+			return error("Invalid hex literal", w);
+		if(slen(w) == 3) {
+			if(!writelitbyte(shex(w + 1))) return 0;
+		} else if(slen(w) == 5) {
+			if(!writeshort(shex(w + 1), 1)) return 0;
+		}
+		break;
+	case '.': /* literal byte zero-page */
+		makereference(p.scope, w, p.ptr - litlast);
+		if(!writelitbyte(0xff)) return 0;
+		break;
+	case ',': /* literal byte relative */
+		makereference(p.scope, w, p.ptr - litlast);
+		if(!writelitbyte(0xff)) return 0;
+		break;
+	case ';': /* literal short absolute */
+		makereference(p.scope, w, p.ptr);
+		if(!writeshort(0xffff, 1)) return 0;
+		break;
+	case ':': /* raw short absolute */
+		makereference(p.scope, w, p.ptr);
+		if(!writeshort(0xffff, 0)) return 0;
+		break;
+	case '\'': /* raw char */
+		if(!writebyte((Uint8)w[1])) return 0;
+		break;
+	case '"': /* raw string */
+		i = 0;
+		while((c = w[++i]))
+			if(!writebyte(c)) return 0;
+		break;
+	case '[':
+	case ']':
+		if(slen(w) == 1) break; /* else fallthrough */
+	default:
+		/* opcode */
+		if(findopcode(w) || scmp(w, "BRK", 4)) {
+			if(!writeopcode(w)) return 0;
+		}
+		/* raw byte */
+		else if(sihx(w) && slen(w) == 2) {
+			if(!writebyte(shex(w))) return 0;
+		}
+		/* raw short */
+		else if(sihx(w) && slen(w) == 4) {
+			if(!writeshort(shex(w), 0)) return 0;
+		}
+		/* macro */
+		else if((m = findmacro(w))) {
+			for(i = 0; i < m->len; i++)
+				if(!parse(m->items[i], f))
+					return 0;
+			return 1;
+		} else
+			return error("Unknown token", w);
+	}
+	return 1;
+}
+
+static int
+resolve(void)
+{
+	Label *l;
+	int i;
+	for(i = 0; i < p.rlen; i++) {
+		Reference *r = &p.refs[i];
+		switch(r->rune) {
+		case '.':
+			if(!(l = findlabel(r->name)))
+				return error("Unknown zero-page reference", r->name);
+			p.data[r->addr + 1] = l->addr & 0xff;
+			l->refs++;
+			break;
+		case ',':
+			if(!(l = findlabel(r->name)))
+				return error("Unknown relative reference", r->name);
+			p.data[r->addr + 1] = (Sint8)(l->addr - r->addr - 3);
+			if((Sint8)p.data[r->addr + 1] != (l->addr - r->addr - 3))
+				return error("Relative reference is too far", r->name);
+			l->refs++;
+			break;
+		case ';':
+			if(!(l = findlabel(r->name)))
+				return error("Unknown absolute reference", r->name);
+			p.data[r->addr + 1] = l->addr >> 0x8;
+			p.data[r->addr + 2] = l->addr & 0xff;
+			l->refs++;
+			break;
+		case ':':
+			if(!(l = findlabel(r->name)))
+				return error("Unknown absolute reference", r->name);
+			p.data[r->addr + 0] = l->addr >> 0x8;
+			p.data[r->addr + 1] = l->addr & 0xff;
+			l->refs++;
+			break;
+		default:
+			return error("Unknown reference", r->name);
+		}
+	}
+	return 1;
+}
+
+static int
+assemble(FILE *f)
+{
+	char w[0x40];
+	scpy("on-reset", p.scope, 0x40);
+	while(fscanf(f, "%63s", w) == 1)
+		if(!parse(w, f))
+			return error("Unknown token", w);
+	return resolve();
+}
+
+static void
+review(char *filename)
+{
+	int i;
+	for(i = 0; i < p.llen; i++)
+		if(p.labels[i].name[0] >= 'A' && p.labels[i].name[0] <= 'Z')
+			continue; /* Ignore capitalized labels(devices) */
+		else if(!p.labels[i].refs)
+			fprintf(stderr, "-- Unused label: %s\n", p.labels[i].name);
+	fprintf(stderr,
+		"Assembled %s in %d bytes(%.2f%% used), %d labels, %d macros.\n",
+		filename,
+		p.length - TRIM,
+		(p.length - TRIM) / 652.80,
+		p.llen,
+		p.mlen);
+}
+
+int
+main(int argc, char *argv[])
+{
+	FILE *src, *dst;
+	if(argc < 3)
+		return !error("usage", "input.tal output.rom");
+	if(!(src = fopen(argv[1], "r")))
+		return !error("Invalid input", argv[1]);
+	if(!assemble(src))
+		return !error("Assembly", "Failed to assemble rom.");
+	if(!(dst = fopen(argv[2], "wb")))
+		return !error("Invalid Output", argv[2]);
+	if(p.length <= TRIM)
+		return !error("Assembly", "Output rom is empty.");
+	fwrite(p.data + TRIM, p.length - TRIM, 1, dst);
+	review(argv[2]);
+	return 0;
+}