diff --git a/Makefile b/Makefile
index b59ba65..2ecbed7 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 
 CC=cc
 CFLAGS=-O3 -std=c99 -Werror -Wall -Wshadow -Wpointer-arith -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes
-SOURCES=cpu.c ins.c pia.c mem.c ewm.c
+SOURCES=cpu.c ins.c pia.c mem.c ewm.c fmt.c
 OBJECTS=$(SOURCES:.c=.o)
 LIBS=-lcurses
 EXECUTABLE=ewm
diff --git a/cpu.c b/cpu.c
index b86db17..8313f74 100644
--- a/cpu.c
+++ b/cpu.c
@@ -21,6 +21,7 @@
 // SOFTWARE.
 
 #include <assert.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <string.h>
@@ -34,6 +35,7 @@
 #include "cpu.h"
 #include "ins.h"
 #include "mem.h"
+#include "fmt.h"
 
 /* Private API */
 
@@ -97,125 +99,6 @@ void _cpu_set_status(struct cpu_t *cpu, uint8_t status) {
   cpu->state.c = (status & (1 << 0));
 }
 
-static void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
-   *buffer = 0x00;
-
-   cpu_instruction_t *i = &instructions[mem_get_byte(cpu, cpu->state.pc)];
-   uint8_t opcode = mem_get_byte(cpu, cpu->state.pc);
-
-   /* Single byte instructions */
-   if (i->bytes == 1) {
-      sprintf(buffer, "%s", i->name);
-   }
-
-   /* JSR is the only exception */
-   else if (opcode == 0x20) {
-     sprintf(buffer, "%s $%.4X", i->name, mem_get_word(cpu, cpu->state.pc+1));
-   }
-
-   /* Branches */
-   else if ((opcode & 0b00011111) == 0b00010000) {
-      int8_t offset = (int8_t) mem_get_byte(cpu, cpu->state.pc+1);
-      uint16_t addr = cpu->state.pc + 2 + offset;
-      sprintf(buffer, "%s $%.4X", i->name, addr);
-   }
-
-   else if ((opcode & 0b00000011) == 0b00000001) {
-      switch ((opcode & 0b00011100) >> 2) {
-         case 0b000:
-            sprintf(buffer, "%s ($%.2X,X)", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b001:
-            sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b010:
-            sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b011:
-            sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b100:
-            sprintf(buffer, "%s ($%.2X),Y", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b101:
-            sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b110:
-            sprintf(buffer, "%s $%.2X%.2X,Y", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b111:
-            sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-      }
-   }
-
-   else if ((opcode & 0b00000011) == 0b00000010) {
-      switch ((opcode & 0b00011100) >> 2) {
-         case 0b000:
-            sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b001:
-            sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b010:
-            sprintf(buffer, "%s", i->name);
-            break;
-         case 0b011:
-            sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b101:
-            sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b111:
-            sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-      }
-   }
-
-   else if ((opcode & 0b00000011) == 0b00000000) {
-      switch ((opcode & 0b00011100) >> 2) {
-         case 0b000:
-            sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b001:
-            sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b011:
-            sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b101:
-            sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-         case 0b111:
-            sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
-            break;
-      }
-   }
-}
-
-static void cpu_format_state(struct cpu_t *cpu, char *buffer) {
-   sprintf(buffer, "A=%.2X X=%.2X Y=%.2X S=%.2X SP=%.4X %c%c%c%c%c%c%c%c",
-           cpu->state.a, cpu->state.x, cpu->state.y, cpu->state.s, 0x0100 + cpu->state.sp,
-
-           cpu->state.n ? 'N' : '-',
-           cpu->state.v ? 'V' : '-',
-           '-',
-           cpu->state.b ? 'B' : '-',
-           cpu->state.d ? 'D' : '-',
-           cpu->state.i ? 'I' : '-',
-           cpu->state.z ? 'Z' : '-',
-           cpu->state.c ? 'C' : '-');
-}
-
-static void cpu_format_stack(struct cpu_t *cpu, char *buffer) {
-   *buffer = 0x00;
-   for (uint16_t sp = cpu->state.sp; sp != 0xff; sp++) {
-      char tmp[8];
-      sprintf(tmp, " %.2X", _mem_get_byte_direct(cpu, 0x0100 + sp));
-      buffer = strcat(buffer, tmp);
-   }
-}
-
 static int cpu_execute_instruction(struct cpu_t *cpu) {
    /* Trace code - Refactor into its own function or module */
    char trace_instruction[256];
@@ -268,22 +151,23 @@ static int cpu_execute_instruction(struct cpu_t *cpu) {
 
    if (cpu->trace) {
       cpu_format_state(cpu, trace_state);
-      cpu_format_stack(cpu, trace_stack); // TODO: This crashes on the hello world test
+      cpu_format_stack(cpu, trace_stack);
 
+      char bytes[10];
       switch (i->bytes) {
          case 1:
-            fprintf(stderr, "CPU: %.4X %-20s | %.2X           %-20s  STACK: %s\n",
-                    pc, trace_instruction, mem_get_byte(cpu, pc), trace_state, trace_stack);
+            snprintf(bytes, sizeof bytes, "%.2X", mem_get_byte(cpu, pc));
             break;
          case 2:
-            fprintf(stderr, "CPU: %.4X %-20s | %.2X %.2X        %-20s  STACK: %s\n",
-                    pc, trace_instruction, mem_get_byte(cpu, pc), mem_get_byte(cpu, pc+1), trace_state, trace_stack);
+            snprintf(bytes, sizeof bytes, "%.2X %.2X", mem_get_byte(cpu, pc), mem_get_byte(cpu, pc+1));
             break;
          case 3:
-            fprintf(stderr, "CPU: %.4X %-20s | %.2X %.2X %.2X     %-20s  STACK: %s\n",
-                    pc, trace_instruction, mem_get_byte(cpu, pc), mem_get_byte(cpu, pc+1), mem_get_byte(cpu, pc+2), trace_state, trace_stack);
+            snprintf(bytes, sizeof bytes, "%.2X %.2X %.2X", mem_get_byte(cpu, pc), mem_get_byte(cpu, pc+1), mem_get_byte(cpu, pc+2));
             break;
       }
+      
+      fprintf(cpu->trace, "%.4X: %-8s  %-11s  %-20s  %s\n",
+              pc, bytes, trace_instruction, trace_state, trace_stack);
    }
 
    return 0;
@@ -295,6 +179,13 @@ void cpu_init(struct cpu_t *cpu) {
    memset(cpu, 0x00, sizeof(struct cpu_t));
 }
 
+void cpu_shutdown(struct cpu_t *cpu) {
+   if (cpu->trace != NULL) {
+      (void) fclose(cpu->trace);
+      cpu->trace = NULL;
+   }
+}
+
 void cpu_add_mem(struct cpu_t *cpu, struct mem_t *mem) {
   if (cpu->mem == NULL) {
     cpu->mem = mem;
@@ -405,13 +296,25 @@ void cpu_strict(struct cpu_t *cpu, bool strict) {
    cpu->strict = true;
 }
 
-void cpu_trace(struct cpu_t *cpu, uint8_t trace) {
-   cpu->trace = trace;
+int cpu_trace(struct cpu_t *cpu, char *path) {
+   if (cpu->trace != NULL) {
+      (void) fclose(cpu->trace);
+      cpu->trace = NULL;
+   }
+
+   if (path != NULL) {
+      printf("MOO Tracing to %s\n", path);
+      cpu->trace = fopen(path, "w");
+      if (cpu->trace == NULL) {
+         return errno;
+      }
+   }
+
+   return 0;
 }
 
 void cpu_reset(struct cpu_t *cpu) {
    cpu->state.pc = mem_get_word(cpu, EWM_VECTOR_RES);
-   fprintf(stderr, "CPU: cpu->state.pc = %.4x\n", cpu->state.pc);
    cpu->state.a = 0x00;
    cpu->state.x = 0x00;
    cpu->state.y = 0x00;
@@ -458,7 +361,6 @@ int cpu_run(struct cpu_t *cpu) {
       /* TODO: Tick? */
       instruction_count++;
    }
-   fprintf(stderr, "Executed %" PRId64 " instructions\n", instruction_count);
    return err;
 }
 
diff --git a/cpu.h b/cpu.h
index f52cf4d..488cd59 100644
--- a/cpu.h
+++ b/cpu.h
@@ -41,11 +41,11 @@ struct cpu_state_t {
 };
 
 struct cpu_t {
-  struct cpu_state_t state;
-  uint8_t trace;
-  bool strict;
-  struct mem_t *mem;
-  uint8_t *memory; // This is pointing to the first 2 pages of memory, zero page and stack.
+   struct cpu_state_t state;
+   FILE *trace;
+   bool strict;
+   struct mem_t *mem;
+   uint8_t *memory; // This is pointing to the first 2 pages of memory, zero page and stack.
 };
 
 #define MEM_TYPE_RAM 0
@@ -79,6 +79,7 @@ uint8_t _cpu_get_status(struct cpu_t *cpu);
 void _cpu_set_status(struct cpu_t *cpu, uint8_t status);
 
 void cpu_init(struct cpu_t *cpu);
+void cpu_shutdown(struct cpu_t *cpu);
 
 void cpu_add_mem(struct cpu_t *cpu, struct mem_t *mem);
 void cpu_add_ram(struct cpu_t *cpu, uint16_t start, uint16_t length);
@@ -87,7 +88,7 @@ void cpu_add_rom_data(struct cpu_t *cpu, uint16_t start, uint16_t length, uint8_
 void cpu_add_iom(struct cpu_t *cpu, uint16_t start, uint16_t length, void *obj, mem_read_handler_t read_handler, mem_write_handler_t write_handler);
 
 void cpu_strict(struct cpu_t *cpu, bool strict);
-void cpu_trace(struct cpu_t *cpu, uint8_t trace);
+int cpu_trace(struct cpu_t *cpu, char *path);
 
 void cpu_reset(struct cpu_t *cpu);
 int cpu_irq(struct cpu_t *cpu);
diff --git a/ewm.c b/ewm.c
index 5622820..b06e984 100644
--- a/ewm.c
+++ b/ewm.c
@@ -83,6 +83,7 @@ static struct ewm_machine_t machines[] = {
 static struct option options[] = {
    { "machine", required_argument, NULL, 'm' },
    { "strict",  no_argument,       NULL, 's' },
+   { "trace",   optional_argument, NULL, 't' },
    { NULL,      0,                 NULL, 0   }
 };
 
@@ -98,6 +99,7 @@ static struct ewm_machine_t *machine_with_name(char *name) {
 int main(int argc, char **argv) {
    struct ewm_machine_t *machine = NULL;
    bool strict = false;
+   char *trace_path = NULL;
 
    char ch;
    while ((ch = getopt_long(argc, argv, "m:", options, NULL)) != -1) {
@@ -108,6 +110,9 @@ int main(int argc, char **argv) {
          case 's':
             strict = true;
             break;
+         case 't':
+            trace_path = optarg ? optarg : "/dev/stderr";
+            break;
       }
    }
 
@@ -122,6 +127,7 @@ int main(int argc, char **argv) {
    struct cpu_t cpu;
    cpu_init(&cpu);
    cpu_strict(&cpu, strict);
+   cpu_trace(&cpu, trace_path);
 
    (void) setup_replica1(&cpu);
 
@@ -138,5 +144,7 @@ int main(int argc, char **argv) {
          break;
    }
 
+   cpu_shutdown(&cpu);
+
    return 0;
 }
diff --git a/fmt.c b/fmt.c
new file mode 100644
index 0000000..516102c
--- /dev/null
+++ b/fmt.c
@@ -0,0 +1,156 @@
+// The MIT License (MIT)
+//
+// Copyright (c) 2015 Stefan Arentz - http://github.com/st3fan/ewm
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#include <stdio.h>
+#include <string.h>
+
+#include "cpu.h"
+#include "ins.h"
+#include "mem.h"
+#include "fmt.h"
+
+void cpu_format_state(struct cpu_t *cpu, char *buffer) {
+   sprintf(buffer, "A=%.2X X=%.2X Y=%.2X S=%.2X SP=%.2X %c%c%c%c%c%c%c%c",
+           cpu->state.a, cpu->state.x, cpu->state.y, _cpu_get_status(cpu), cpu->state.sp,
+
+           cpu->state.n ? 'N' : '-',
+           cpu->state.v ? 'V' : '-',
+           '-',
+           cpu->state.b ? 'B' : '-',
+           cpu->state.d ? 'D' : '-',
+           cpu->state.i ? 'I' : '-',
+           cpu->state.z ? 'Z' : '-',
+           cpu->state.c ? 'C' : '-');
+}
+
+void cpu_format_stack(struct cpu_t *cpu, char buffer[764]) {
+   if (cpu->state.sp != 0xff) {
+      char *p = buffer;
+      *p = 0x00;
+      p = strcat(p, "[");
+      for (uint16_t sp = cpu->state.sp; sp != 0xff; sp++) {
+         if (sp != cpu->state.sp) {
+            p = strcat(p, " ");
+         }
+         char tmp[8];
+         sprintf(tmp, "%.2X", _mem_get_byte_direct(cpu, 0x0100 + sp));
+         p = strcat(p, tmp);
+      }
+      strcat(p, "]");
+   }
+}
+
+void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
+   *buffer = 0x00;
+
+   cpu_instruction_t *i = &instructions[mem_get_byte(cpu, cpu->state.pc)];
+   uint8_t opcode = mem_get_byte(cpu, cpu->state.pc);
+
+   /* Single byte instructions */
+   if (i->bytes == 1) {
+      sprintf(buffer, "%s", i->name);
+   }
+
+   /* JSR is the only exception */
+   else if (opcode == 0x20) {
+     sprintf(buffer, "%s $%.4X", i->name, mem_get_word(cpu, cpu->state.pc+1));
+   }
+
+   /* Branches */
+   else if ((opcode & 0b00011111) == 0b00010000) {
+      int8_t offset = (int8_t) mem_get_byte(cpu, cpu->state.pc+1);
+      uint16_t addr = cpu->state.pc + 2 + offset;
+      sprintf(buffer, "%s $%.4X", i->name, addr);
+   }
+
+   else if ((opcode & 0b00000011) == 0b00000001) {
+      switch ((opcode & 0b00011100) >> 2) {
+         case 0b000:
+            sprintf(buffer, "%s ($%.2X,X)", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b001:
+            sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b010:
+            sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b011:
+            sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b100:
+            sprintf(buffer, "%s ($%.2X),Y", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b101:
+            sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b110:
+            sprintf(buffer, "%s $%.2X%.2X,Y", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b111:
+            sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+      }
+   }
+
+   else if ((opcode & 0b00000011) == 0b00000010) {
+      switch ((opcode & 0b00011100) >> 2) {
+         case 0b000:
+            sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b001:
+            sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b010:
+            sprintf(buffer, "%s", i->name);
+            break;
+         case 0b011:
+            sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b101:
+            sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b111:
+            sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+      }
+   }
+
+   else if ((opcode & 0b00000011) == 0b00000000) {
+      switch ((opcode & 0b00011100) >> 2) {
+         case 0b000:
+            sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b001:
+            sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b011:
+            sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b101:
+            sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+         case 0b111:
+            sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
+            break;
+      }
+   }
+}
diff --git a/fmt.h b/fmt.h
new file mode 100644
index 0000000..435c187
--- /dev/null
+++ b/fmt.h
@@ -0,0 +1,32 @@
+// The MIT License (MIT)
+//
+// Copyright (c) 2015 Stefan Arentz - http://github.com/st3fan/ewm
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#ifndef EWM_FMT_H
+#define EWM_FMT_H
+
+struct cpu_t;
+
+void cpu_format_state(struct cpu_t *cpu, char *buffer);
+void cpu_format_stack(struct cpu_t *cpu, char buffer[764]);
+void cpu_format_instruction(struct cpu_t *cpu, char *buffer);
+
+#endif /* EWM_FMT_H */
diff --git a/mem.c b/mem.c
index 23b78ec..4f5f47c 100644
--- a/mem.c
+++ b/mem.c
@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "cpu.h"
 #include "mem.h"
 
 // The following two are our memory primitives that properly set go
diff --git a/mem.h b/mem.h
index cc763e4..b193d8c 100644
--- a/mem.h
+++ b/mem.h
@@ -23,7 +23,7 @@
 #ifndef MEM_H
 #define MEM_H
 
-#include "cpu.h"
+struct cpu_t;
 
 typedef uint8_t (*mem_mod_t)(struct cpu_t *cpu, uint8_t b);