diff --git a/4ed_os_comp_cracking.h b/4ed_os_comp_cracking.h
index cb695ded..e7c43797 100644
--- a/4ed_os_comp_cracking.h
+++ b/4ed_os_comp_cracking.h
@@ -12,7 +12,7 @@
 #if !defined(FRED_OS_COMP_CRACKING_H)
 #define FRED_OS_COMP_CRACKING_H
 
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) /* COMPILER */
 
 # define IS_CL
 
@@ -21,20 +21,30 @@
 # define snprintf _snprintf
 #endif
 
-# if defined(_WIN32)
+# if defined(_WIN32) /* OS */
 #  define IS_WINDOWS
 #  pragma comment(lib, "Kernel32.lib")
 # else
 #  error This compiler/platform combo is not supported yet
 # endif
 
+# if defined(_M_AMD64) /* Arch */
+#  define CALL_CONVENTION
+#  define BUILD_X64
+# elif defined(_M_IX86)
+#  define CALL_CONVENTION __stdcall
+#  define BUILD_X86
+# else
+#  error architecture not supported yet
+# endif
+
 #elif defined(__GNUC__) || defined(__GNUG__)
 
-# define IS_GCC
+# define IS_GCC /* COMPILER */
 
-# if defined(__gnu_linux__)
+# if defined(__gnu_linux__) /* OS */
 #  define IS_LINUX
-# elif defined(__APPLE__) && defined(__MACH__)
+# elif defined(__APPLE__) && defined(__MACH__) /* OS */
 #  define IS_MAC
 #else
 #  error This compiler/platform combo is not supported yet
@@ -44,7 +54,6 @@
 #error This compiler is not supported yet
 #endif
 
-
 #endif
 
 // BOTTOM
diff --git a/4ed_profile.cpp b/4ed_profile.cpp
deleted file mode 100644
index 6926f3f8..00000000
--- a/4ed_profile.cpp
+++ /dev/null
@@ -1,217 +0,0 @@
-/*
- * Mr. 4th Dimention - Allen Webster
- *
- * 29.03.2017
- *
- * Really basic profiling primitives. (not meant to stay for long)
- *
- */
-
-// TOP
-
-#define FRED_INTERNAL 1
-
-#include "4tech_defines.h"
-#include "4ed_profile.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-
-global f32 frame_target = 58000000.f;
-
-internal void
-usage(){
-    fprintf(stderr, "No! Like this, you moron:\n"
-            "\t<PROFILE-EXE> <PROFILE-DATA> [min-time-filter]\n");
-}
-
-internal u32
-parse_frame_count(u8 *ptr, u8 *end){
-    u32 count = 0;
-    
-    for (;ptr < end;){
-        u8 *frame_base = *(u8**)ptr;
-        ptr += 8;
-        
-        u8 *frame_end = *(u8**)ptr;
-        ptr += 8;
-        
-        umem skip_size = frame_end - frame_base;
-        ptr += skip_size;
-        ++count;
-    }
-    
-    if (ptr != end){
-        count = 0;
-    }
-    
-    return(count);
-}
-
-struct Parse_Frame_Result{
-    u8 *next_read_ptr;
-    u8 *output_chunk;
-    b32 still_looping;
-    b32 bad_parse;
-    f32 frame_time;
-};
-
-internal Parse_Frame_Result
-parse_frame(u8 *ptr, u8 *end_ptr){
-    Parse_Frame_Result result = {0};
-    
-    u8 *frame_base = *(u8**)ptr;
-    ptr += 8;
-    
-    u8 *frame_end = *(u8**)ptr;
-    ptr += 8;
-    
-    umem frame_size = frame_end - frame_base;
-    u8 *frame_start_ptr = ptr;
-    u8 *frame_end_ptr = ptr + frame_size;
-    
-    u8 *out_chunk = (u8*)malloc(frame_size*2);
-    u8 *out_ptr = out_chunk;
-    
-    Profile_Group *group = (Profile_Group*)frame_start_ptr;
-    Profile_Group *group_end = (Profile_Group*)frame_end_ptr;
-    
-    Profile_Group *stack[64];
-    u32 top = 0;
-    
-    stack[top++] = group;
-    
-    result.frame_time = group->cycle_count / frame_target;
-    
-    for (;group < group_end;){
-        for (u32 i = 1; i < top; ++i){
-            *out_ptr++ = ' ';
-        }
-        
-        char *name = group->name;
-        for (u32 i = 0; name[i]; ++i){
-            *out_ptr++ = name[i];
-        }
-        
-        *out_ptr++ = ':';
-        *out_ptr++ = ' ';
-        
-        char str[64];
-        sprintf(str, "%f", group->cycle_count / frame_target);
-        for (u32 i = 0; str[i]; ++i){
-            *out_ptr++ = str[i];
-        }
-        *out_ptr++ = '\n';
-        
-        ++group;
-        
-        for(;top > 0;){
-            Profile_Group *group_top = stack[top-1];
-            umem end_offset = (u8*)group_top->end - frame_base;
-            u8 *this_group_end_ptr = frame_start_ptr + end_offset;
-            Profile_Group *this_group_end = (Profile_Group*)this_group_end_ptr;
-            
-            if (group == this_group_end){
-                --top;
-            }
-            else{
-                break;
-            }
-        }
-        
-        stack[top++] = group;
-    }
-    
-    if (top != 1){
-        result.bad_parse = true;
-    }
-    else{
-        *out_ptr++ = 0;
-        result.next_read_ptr = frame_end_ptr;
-        result.output_chunk = out_chunk;
-        if (frame_end_ptr != end_ptr){
-            result.still_looping = true;
-        }
-    }
-    
-    return(result);
-}
-
-internal void
-print_profile(char *filename, f32 min_filter){
-    FILE *file = fopen(filename, "rb");
-    if (!file){
-        fprintf(stderr, "There ain't no file sittin' around called %s.\n", filename);
-        exit(1);
-    }
-    
-    fseek(file, 0, SEEK_END);
-    u32 size = ftell(file);
-    fseek(file, 0, SEEK_SET);
-    
-    u8 *buffer = (u8*)malloc(size);
-    
-    fread(buffer, 1, size, file);
-    fclose(file);
-    
-    u8 *read_ptr = buffer;
-    u8 *end_ptr = buffer + size;
-    
-    // Frame Count Parse
-    u32 frame_count = parse_frame_count(read_ptr, end_ptr);
-    
-    if (frame_count == 0){
-        fprintf(stderr, "There's some fricken problem. I didn't get a good frame count!\n");
-        exit(1);
-    }
-    
-    // Full Parse
-    u8 **output_chunks = (u8**)malloc(frame_count*sizeof(u8*));
-    u32 chunk_i = 0;
-    
-    Parse_Frame_Result result = {0};
-    do{
-        if (chunk_i >= frame_count){
-            fprintf(stderr, "The parse ain't lined up! You're fired!\n");
-            exit(1);
-        }
-        
-        result = parse_frame(read_ptr, end_ptr);
-        
-        if (result.bad_parse){
-            fprintf(stderr, "You've pickled the data nimwit!\n");
-            exit(1);
-        }
-        
-        read_ptr = result.next_read_ptr;
-        if (result.frame_time >= min_filter){
-            output_chunks[chunk_i++] = result.output_chunk;
-        }
-    }while(result.still_looping);
-    
-    // Print
-    fprintf(stdout, "Frames: %u (%u)\n", chunk_i, frame_count);
-    for (u32 i = 0; i < chunk_i; ++i){
-        fprintf(stdout, "%s", output_chunks[i]);
-    }
-}
-
-int main(int argc, char **argv){
-    if (argc < 2){
-        usage();
-    }
-    else{
-        f32 min_filter = 0.f;
-        if (argc == 3){
-            min_filter = (f32)atof(argv[2]);
-        }
-        
-        print_profile(argv[1], min_filter);
-    }
-    return(0);
-}
-
-// BOTTOM
-
-
-
diff --git a/4ed_profile.h b/4ed_profile.h
deleted file mode 100644
index 89e7048e..00000000
--- a/4ed_profile.h
+++ /dev/null
@@ -1,162 +0,0 @@
-/*
- * Mr. 4th Dimention - Allen Webster
- *
- * 29.03.2017
- *
- * Really basic profiling primitives. (not meant to stay for long)
- *
- */
-
-// TOP
-
-#if !defined(FRED_PROFILE_H)
-#define FRED_PROFILE_H
-
-#if FRED_INTERNAL && IS_MSVC
-
-#include <intrin.h>
-#include <stdio.h>
-
-struct Profile_Group{
-    char name[104];
-    u64 cycle_start;
-    u64 cycle_count;
-    void *end;
-};
-
-struct Profile{
-    u8 *buffer;
-    u32 pos, max;
-    
-    Profile_Group *stack[64];
-    u32 stack_top;
-};
-global Profile global_profile = {0};
-
-internal Profile_Group*
-push_group(char *name){
-    Profile_Group *result = 0;
-    if (global_profile.pos + sizeof(Profile_Group) <= global_profile.max){
-        result = (Profile_Group*)(global_profile.buffer + global_profile.pos);
-        global_profile.pos += sizeof(Profile_Group);
-        u32 i = 0;
-        for (; name[i] && i < sizeof(result->name)-1; ++i){
-            result->name[i] = name[i];
-        }
-        result->name[i] = 0;
-        result->cycle_start = __rdtsc();
-    }
-    return(result);
-}
-
-internal void
-profile_init(void *mem, u32 max){
-    global_profile.buffer = (u8*)mem;
-    global_profile.max = max;
-}
-
-internal void
-profile_begin_group(char *name){
-    u32 stack_pos = global_profile.stack_top;
-    if (stack_pos < ArrayCount(global_profile.stack)){
-        global_profile.stack[stack_pos] = push_group(name);
-        Assert(global_profile.stack[stack_pos] != 0);
-        ++global_profile.stack_top;
-    }
-}
-
-internal void
-profile_end_group(){
-    Assert(global_profile.stack_top > 0);
-    u32 stack_pos = --global_profile.stack_top;
-    if (stack_pos < ArrayCount(global_profile.stack)){
-        Profile_Group *group = global_profile.stack[stack_pos];
-        Assert(group != 0);
-        group->cycle_count = __rdtsc() - group->cycle_start;
-        group->end = global_profile.buffer + global_profile.pos;
-    }
-}
-
-internal void
-profile_begin_frame(){
-    global_profile.pos = 0;
-    global_profile.stack_top = 0;
-    profile_begin_group("*frame*");
-}
-
-internal void
-profile_end_frame(char *filename){
-    profile_end_group();
-    Assert(global_profile.stack_top == 0);
-    
-    FILE *file = fopen(filename, "ab");
-    Assert(file != 0);
-    fwrite(&global_profile.buffer, 8, 1, file);
-    
-    Profile_Group *first_group = (Profile_Group*)global_profile.buffer;
-    fwrite(&first_group->end, 8, 1, file);
-    
-    fwrite(global_profile.buffer, 1, global_profile.pos, file);
-    fclose(file);
-}
-
-internal Profile_Group*
-profile_begin_resumable(char *name){
-    Profile_Group *result = push_group(name);
-    Assert(result != 0);
-    result->cycle_count = 0;
-    result->end = result + 1;
-    return(result);
-}
-
-struct profile_scope{
-    profile_scope(char *name){
-        profile_begin_group(name);
-    }
-    
-    ~profile_scope(){
-        profile_end_group();
-    }
-};
-
-#define PRFL_INIT(m,s) profile_init(m,s)
-
-#define PRFL_BEGIN_FRAME() profile_begin_frame()
-#define PRFL_END_FRAME(n) profile_end_frame(n)
-
-#define PRFL_BEGIN_GROUP(n) profile_begin_group(#n)
-#define PRFL_END_GROUP() profile_end_group()
-#define PRFL_SCOPE_GROUP(n) profile_scope SCOPE_##n(#n)
-
-#define PRFL_FUNC_GROUP() profile_scope SCOPE_FUNC(__FUNCTION__)
-
-#define PRFL_BEGIN_RESUMABLE(n) Profile_Group *PRFLGRP_##n = profile_begin_resumable(#n)
-#define PRFL_START_RESUMABLE(n) PRFLGRP_##n->cycle_start = __rdtsc()
-#define PRFL_STOP_RESUMABLE(n) PRFLGRP_##n->cycle_count += __rdtsc() - PRFLGRP_##n->cycle_start
-#define PRFL_END_RESUMABLE(n)
-
-#else
-
-#define PRFL_INIT(m,s)
-
-#define PRFL_BEGIN_FRAME()
-#define PRFL_END_FRAME(n)
-
-#define PRFL_BEGIN_GROUP(n)
-#define PRFL_END_GROUP()
-#define PRFL_SCOPE_GROUP(n)
-
-#define PRFL_FUNC_GROUP()
-
-#define PRFL_BEGIN_RESUMABLE(n)
-#define PRFL_START_RESUMABLE(n)
-#define PRFL_STOP_RESUMABLE(n)
-#define PRFL_END_RESUMABLE(n)
-
-#endif
-
-#endif
-
-// BOTTOM
-
-
diff --git a/platform_all/4ed_link_system_functions.cpp b/platform_all/4ed_link_system_functions.cpp
index 85764045..3f9968b2 100644
--- a/platform_all/4ed_link_system_functions.cpp
+++ b/platform_all/4ed_link_system_functions.cpp
@@ -59,7 +59,7 @@ link_system_code(System_Functions *system){
     SYSLINK(send_exit_signal);
     
     SYSLINK(log);
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
     SYSLINK(internal_get_thread_states);
 #endif
 }
diff --git a/platform_all/4ed_shared_file_handling.cpp b/platform_all/4ed_shared_file_handling.cpp
new file mode 100644
index 00000000..903f6f19
--- /dev/null
+++ b/platform_all/4ed_shared_file_handling.cpp
@@ -0,0 +1,49 @@
+/*
+ * Mr. 4th Dimention - Allen Webster
+ *
+ * 18.07.2017
+ *
+ * Cross platform logic for work queues.
+ *
+ */
+
+// TOP
+
+internal u32
+directory_cd(char *dir, i32 *len, i32 cap, char *rel_path, i32 rel_len, char slash){
+    String directory = make_string_cap(dir, *len, cap);
+    b32 result = false;
+    
+    if (rel_path[0] != 0){
+        if (rel_path[0] == '.' && rel_path[1] == 0){
+            result = true;
+        }
+        else if (rel_path[0] == '.' && rel_path[1] == '.' && rel_path[2] == 0){
+            result = remove_last_folder(&directory);
+            terminate_with_null(&directory);
+        }
+        else{
+            if (directory.size + rel_len + 1 > directory.memory_size){
+                i32 old_size = directory.size;
+                append_partial_sc(&directory, rel_path);
+                append_s_char(&directory, slash);
+                terminate_with_null(&directory);
+                
+                if (system_directory_exists(directory.str)){
+                    result = true;
+                }
+                else{
+                    directory.size = old_size;
+                }
+            }
+        }
+    }
+    
+    *len = directory.size;
+    LOGF("%.*s: %d\n", directory.size, directory.str, result);
+    
+    return(result);
+}
+
+// BOTTOM
+
diff --git a/platform_all/4ed_shared_thread_constants.h b/platform_all/4ed_shared_thread_constants.h
index 93ac0a7b..c72a4c28 100644
--- a/platform_all/4ed_shared_thread_constants.h
+++ b/platform_all/4ed_shared_thread_constants.h
@@ -1,7 +1,7 @@
 /*
  * Mr. 4th Dimention - Allen Webster
  *
- * 17.07.2017
+ * 18.07.2017
  *
  * Cross platform threading constants
  *
diff --git a/platform_linux/linux_4ed.cpp b/platform_linux/linux_4ed.cpp
index bab09806..b371699d 100644
--- a/platform_linux/linux_4ed.cpp
+++ b/platform_linux/linux_4ed.cpp
@@ -596,7 +596,7 @@ ctxErrorHandler( Display *dpy, XErrorEvent *ev )
     return 0;
 }
 
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
 
 static void LinuxGLDebugCallback(
 GLenum source,
@@ -646,7 +646,7 @@ InitializeOpenGLContext(Display *XDisplay, Window XWindow, GLXFBConfig &bestFbc,
             GLX_CONTEXT_MAJOR_VERSION_ARB, 4,
             GLX_CONTEXT_MINOR_VERSION_ARB, 3,
             GLX_CONTEXT_PROFILE_MASK_ARB , GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB,
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
             GLX_CONTEXT_FLAGS_ARB        , GLX_CONTEXT_DEBUG_BIT_ARB,
 #endif
             None
@@ -775,7 +775,7 @@ InitializeOpenGLContext(Display *XDisplay, Window XWindow, GLXFBConfig &bestFbc,
         LOG("VSync enabled? nope, no suitable extension\n");
     }
     
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
     typedef PFNGLDEBUGMESSAGECALLBACKARBPROC glDebugMessageCallbackProc;
     
     GLXLOAD(glDebugMessageCallback);
diff --git a/platform_linux/linux_threading_wrapper.h b/platform_linux/linux_threading_wrapper.h
index 95b27001..5409fe72 100644
--- a/platform_linux/linux_threading_wrapper.h
+++ b/platform_linux/linux_threading_wrapper.h
@@ -1,14 +1,12 @@
 /*
  * Mr. 4th Dimention - Allen Webster
  *
- * 17.07.2017
+ * 18.07.2017
  *
  * Linux threading wrapper
  *
  */
 
-// TODO(allen): Can this just be placed in UNIX?  If so do that.
-
 // TOP
 
 #if !defined(LINUX_THREADING_WRAPPER)
diff --git a/platform_unix/unix_4ed_functions.cpp b/platform_unix/unix_4ed_functions.cpp
index 994d14af..646c04a1 100644
--- a/platform_unix/unix_4ed_functions.cpp
+++ b/platform_unix/unix_4ed_functions.cpp
@@ -304,7 +304,7 @@ Sys_Get_Canonical_Sig(system_get_canonical){
         write_p = path;
     }
     
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
     if(len != (write_p - path) || memcmp(filename, path, len) != 0){
         LOGF("[%.*s] -> [%.*s]\n", len, filename, (int)(write_p - path), path);
     }
@@ -320,14 +320,15 @@ Sys_Load_Handle_Sig(system_load_handle){
     b32 result = false;
     
     i32 fd = open(filename, O_RDONLY);
-    if(fd == -1){
+    if (fd == -1){
         LOG("error: open\n");
-    } else {
+    }
+    else{
         *(int*)handle_out = fd;
         result = true;
     }
     
-    return result;
+    return(result);
 }
 
 internal
@@ -431,6 +432,13 @@ Sys_File_Exists_Sig(system_file_exists){
     return(result);
 }
 
+internal b32
+system_directory_exists(char *path){
+    struct stat st;
+    b32 result = (stat(directory.str, &st) == 0 && S_ISDIR(st.st_mode));
+    return(result);
+}
+
 internal
 Sys_Directory_CD_Sig(system_directory_cd){
     String directory = make_string_cap(dir, *len, cap);
@@ -451,8 +459,7 @@ Sys_Directory_CD_Sig(system_directory_cd){
                 append_s_char(&directory, '/');
                 terminate_with_null(&directory);
                 
-                struct stat st;
-                if (stat(directory.str, &st) == 0 && S_ISDIR(st.st_mode)){
+                if (system_directory_exists(directory.str)){
                     result = true;
                 }
                 else{
diff --git a/platform_win32/win32_4ed.cpp b/platform_win32/win32_4ed.cpp
index 9be69940..658d61c8 100644
--- a/platform_win32/win32_4ed.cpp
+++ b/platform_win32/win32_4ed.cpp
@@ -11,19 +11,7 @@
 
 #define IS_PLAT_LAYER
 
-//
-// Architecture cracking
-//
-
-#if defined(_M_AMD64)
-# define CALL_CONVENTION
-# define BUILD_X64
-#elif defined(_M_IX86)
-# define CALL_CONVENTION __stdcall
-# define BUILD_X86
-#else
-# error architecture not supported yet
-#endif
+#include "4ed_os_comp_cracking.h"
 
 
 //
@@ -197,6 +185,8 @@ system_schedule_step(){
     PostMessage(win32vars.window_handle, WM_4coder_ANIMATE, 0, 0);
 }
 
+////////////////////////////////
+
 //
 // 4ed path
 //
@@ -240,6 +230,21 @@ Sys_Log_Sig(system_log){
     }
 }
 
+//
+// Shared system functions (system_shared.h)
+//
+
+internal
+Sys_File_Can_Be_Made_Sig(system_file_can_be_made){
+    HANDLE file = CreateFile_utf8(filename, FILE_APPEND_DATA, 0, 0, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
+    b32 result = false;
+    if (file != 0 && file != INVALID_HANDLE_VALUE){
+        CloseHandle(file);
+        result = true;
+    }
+    return(result);
+}
+
 //
 // Memory
 //
@@ -276,122 +281,10 @@ Sys_Memory_Free_Sig(system_memory_free){
     VirtualFree(ptr, 0, MEM_RELEASE);
 }
 
-//
-// Threads
-//
-
-#include "4ed_work_queues.cpp"
-
-//
-// Coroutines
-//
-
-internal Win32_Coroutine*
-Win32AllocCoroutine(){
-    Win32_Coroutine *result = win32vars.coroutine_free;
-    Assert(result != 0);
-    win32vars.coroutine_free = result->next;
-    return(result);
-}
-
-internal void
-Win32FreeCoroutine(Win32_Coroutine *data){
-    data->next = win32vars.coroutine_free;
-    win32vars.coroutine_free = data;
-}
-
-internal void CALL_CONVENTION
-Win32CoroutineMain(void *arg_){
-    Win32_Coroutine *c = (Win32_Coroutine*)arg_;
-    c->coroutine.func(&c->coroutine);
-    c->done = 1;
-    Win32FreeCoroutine(c);
-    SwitchToFiber(c->coroutine.yield_handle);
-}
-
-internal
-Sys_Create_Coroutine_Sig(system_create_coroutine){
-    Win32_Coroutine *c;
-    Coroutine *coroutine;
-    void *fiber;
-    
-    c = Win32AllocCoroutine();
-    c->done = 0;
-    
-    coroutine = &c->coroutine;
-    
-    fiber = CreateFiber(0, Win32CoroutineMain, coroutine);
-    
-    coroutine->plat_handle = handle_type(fiber);
-    coroutine->func = func;
-    
-    return(coroutine);
-}
-
-internal
-Sys_Launch_Coroutine_Sig(system_launch_coroutine){
-    Win32_Coroutine *c = (Win32_Coroutine*)coroutine;
-    void *fiber;
-    
-    fiber = handle_type(coroutine->plat_handle);
-    coroutine->yield_handle = GetCurrentFiber();
-    coroutine->in = in;
-    coroutine->out = out;
-    
-    SwitchToFiber(fiber);
-    
-    if (c->done){
-        DeleteFiber(fiber);
-        Win32FreeCoroutine(c);
-        coroutine = 0;
-    }
-    
-    return(coroutine);
-}
-
-Sys_Resume_Coroutine_Sig(system_resume_coroutine){
-    Win32_Coroutine *c = (Win32_Coroutine*)coroutine;
-    void *fiber;
-    
-    Assert(c->done == 0);
-    
-    coroutine->yield_handle = GetCurrentFiber();
-    coroutine->in = in;
-    coroutine->out = out;
-    
-    fiber = handle_type(coroutine->plat_handle);
-    
-    SwitchToFiber(fiber);
-    
-    if (c->done){
-        DeleteFiber(fiber);
-        Win32FreeCoroutine(c);
-        coroutine = 0;
-    }
-    
-    return(coroutine);
-}
-
-Sys_Yield_Coroutine_Sig(system_yield_coroutine){
-    SwitchToFiber(coroutine->yield_handle);
-}
-
-
 //
 // Files
 //
 
-internal
-Sys_File_Can_Be_Made_Sig(system_file_can_be_made){
-    HANDLE file = CreateFile_utf8(filename, FILE_APPEND_DATA, 0, 0, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
-    b32 result = false;
-    if (file != 0 && file != INVALID_HANDLE_VALUE){
-        CloseHandle(file);
-        result = true;
-    }
-    return(result);
-}
-
 internal
 Sys_Set_File_List_Sig(system_set_file_list){
     b32 clear_list = true;
@@ -521,34 +414,34 @@ Sys_Set_File_List_Sig(system_set_file_list){
     }
 }
 
-internal u32
-win32_canonical_ascii_name(char *src, u32 len, char *dst, u32 max){
+internal
+Sys_Get_Canonical_Sig(system_get_canonical){
     u32 result = 0;
     
     char src_space[MAX_PATH + 32];
-    if (len < sizeof(src_space) && len >= 2 && ((src[0] >= 'a' && src[0] <= 'z') || (src[0] >= 'A' && src[0] <= 'Z')) && src[1] == ':'){
-        memcpy(src_space, src, len);
+    if (len < sizeof(src_space) && len >= 2 && ((filename[0] >= 'a' && filename[0] <= 'z') || (filename[0] >= 'A' && filename[0] <= 'Z')) && filename[1] == ':'){
+        memcpy(src_space, filename, len);
         src_space[len] = 0;
         
         HANDLE file = CreateFile_utf8((u8*)src_space, GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
         
         if (file != INVALID_HANDLE_VALUE){
-            DWORD final_length = GetFinalPathNameByHandle_utf8(file, (u8*)dst, max, 0);
+            DWORD final_length = GetFinalPathNameByHandle_utf8(file, (u8*)buffer, max, 0);
             
             if (final_length < max && final_length >= 4){
-                if (dst[final_length-1] == 0){
+                if (buffer[final_length-1] == 0){
                     --final_length;
                 }
                 final_length -= 4;
-                memmove(dst, dst+4, final_length);
-                dst[final_length] = 0;
+                memmove(buffer, buffer+4, final_length);
+                buffer[final_length] = 0;
                 result = final_length;
             }
             
             CloseHandle(file);
         }
         else{
-            String src_str = make_string(src, len);
+            String src_str = make_string(filename, len);
             String path_str = path_of_directory(src_str);
             String front_str = front_of_directory(src_str);
             
@@ -558,18 +451,18 @@ win32_canonical_ascii_name(char *src, u32 len, char *dst, u32 max){
             HANDLE dir = CreateFile_utf8((u8*)src_space, FILE_LIST_DIRECTORY, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, 0, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED, 0);
             
             if (dir != INVALID_HANDLE_VALUE){
-                DWORD final_length = GetFinalPathNameByHandle_utf8(dir, (u8*)dst, max, 0);
+                DWORD final_length = GetFinalPathNameByHandle_utf8(dir, (u8*)buffer, max, 0);
                 
                 if (final_length < max && final_length >= 4){
-                    if (dst[final_length-1] == 0){
+                    if (buffer[final_length-1] == 0){
                         --final_length;
                     }
                     final_length -= 4;
-                    memmove(dst, dst+4, final_length);
-                    dst[final_length++] = '\\';
-                    memcpy(dst + final_length, front_str.str, front_str.size);
+                    memmove(buffer, buffer+4, final_length);
+                    buffer[final_length++] = '\\';
+                    memcpy(buffer + final_length, front_str.str, front_str.size);
                     final_length += front_str.size;
-                    dst[final_length] = 0;
+                    buffer[final_length] = 0;
                     result = final_length;
                 }
                 
@@ -581,12 +474,6 @@ win32_canonical_ascii_name(char *src, u32 len, char *dst, u32 max){
     return(result);
 }
 
-internal
-Sys_Get_Canonical_Sig(system_get_canonical){
-    u32 result = win32_canonical_ascii_name(filename, len, buffer, max);
-    return(result);
-}
-
 internal
 Sys_Load_Handle_Sig(system_load_handle){
     b32 result = false;
@@ -666,17 +553,9 @@ Sys_Save_File_Sig(system_save_file){
     return(result);
 }
 
-internal
-Sys_Now_Time_Sig(system_now_time){
-    u64 result = __rdtsc();
-    return(result);
-}
-
-internal b32
-Win32DirectoryExists(char *path){
-    DWORD attrib = GetFileAttributes_utf8((u8*)path);
-    return(attrib != INVALID_FILE_ATTRIBUTES && (attrib & FILE_ATTRIBUTE_DIRECTORY));
-}
+//
+// File System
+//
 
 internal
 Sys_File_Exists_Sig(system_file_exists){
@@ -701,45 +580,137 @@ Sys_File_Exists_Sig(system_file_exists){
     return(result);
 }
 
+internal b32
+system_directory_exists(char *path){
+    DWORD attrib = GetFileAttributes_utf8((u8*)path);
+    return(attrib != INVALID_FILE_ATTRIBUTES && (attrib & FILE_ATTRIBUTE_DIRECTORY));
+}
+
+#include "4ed_shared_file_handling.cpp"
+
 internal
 Sys_Directory_CD_Sig(system_directory_cd){
-    String directory = make_string_cap(dir, *len, cap);
-    b32 result = 0;
-    i32 old_size;
-    
-    char rel_path_space[1024];
-    String rel_path_string = make_fixed_width_string(rel_path_space);
-    copy_ss(&rel_path_string, make_string(rel_path, rel_len));
-    terminate_with_null(&rel_path_string);
-    
-    if (rel_path[0] != 0){
-        if (rel_path[0] == '.' && rel_path[1] == 0){
-            result = 1;
-        }
-        else if (rel_path[0] == '.' && rel_path[1] == '.' && rel_path[2] == 0){
-            result = remove_last_folder(&directory);
-            terminate_with_null(&directory);
-        }
-        else{
-            if (directory.size + rel_len + 1 > directory.memory_size){
-                old_size = directory.size;
-                append_partial_sc(&directory, rel_path);
-                append_s_char(&directory, '\\');
-                if (Win32DirectoryExists(directory.str)){
-                    result = 1;
-                }
-                else{
-                    directory.size = old_size;
-                }
-            }
-        }
-    }
-    
-    *len = directory.size;
-    
+    u32 result = directory_cd(dir, len, cap, rel_path, rel_len, '\\');
     return(result);
 }
 
+//
+// Time
+//
+
+internal
+Sys_Now_Time_Sig(system_now_time){
+    u64 result = __rdtsc();
+    return(result);
+}
+
+////////////////////////////////
+
+//
+// Threads
+//
+
+#include "4ed_work_queues.cpp"
+
+//
+// Coroutines
+//
+
+internal Win32_Coroutine*
+Win32AllocCoroutine(){
+    Win32_Coroutine *result = win32vars.coroutine_free;
+    Assert(result != 0);
+    win32vars.coroutine_free = result->next;
+    return(result);
+}
+
+internal void
+Win32FreeCoroutine(Win32_Coroutine *data){
+    data->next = win32vars.coroutine_free;
+    win32vars.coroutine_free = data;
+}
+
+internal void CALL_CONVENTION
+Win32CoroutineMain(void *arg_){
+    Win32_Coroutine *c = (Win32_Coroutine*)arg_;
+    c->coroutine.func(&c->coroutine);
+    c->done = 1;
+    Win32FreeCoroutine(c);
+    SwitchToFiber(c->coroutine.yield_handle);
+}
+
+internal
+Sys_Create_Coroutine_Sig(system_create_coroutine){
+    Win32_Coroutine *c;
+    Coroutine *coroutine;
+    void *fiber;
+    
+    c = Win32AllocCoroutine();
+    c->done = 0;
+    
+    coroutine = &c->coroutine;
+    
+    fiber = CreateFiber(0, Win32CoroutineMain, coroutine);
+    
+    coroutine->plat_handle = handle_type(fiber);
+    coroutine->func = func;
+    
+    return(coroutine);
+}
+
+internal
+Sys_Launch_Coroutine_Sig(system_launch_coroutine){
+    Win32_Coroutine *c = (Win32_Coroutine*)coroutine;
+    void *fiber;
+    
+    fiber = handle_type(coroutine->plat_handle);
+    coroutine->yield_handle = GetCurrentFiber();
+    coroutine->in = in;
+    coroutine->out = out;
+    
+    SwitchToFiber(fiber);
+    
+    if (c->done){
+        DeleteFiber(fiber);
+        Win32FreeCoroutine(c);
+        coroutine = 0;
+    }
+    
+    return(coroutine);
+}
+
+Sys_Resume_Coroutine_Sig(system_resume_coroutine){
+    Win32_Coroutine *c = (Win32_Coroutine*)coroutine;
+    void *fiber;
+    
+    Assert(c->done == 0);
+    
+    coroutine->yield_handle = GetCurrentFiber();
+    coroutine->in = in;
+    coroutine->out = out;
+    
+    fiber = handle_type(coroutine->plat_handle);
+    
+    SwitchToFiber(fiber);
+    
+    if (c->done){
+        DeleteFiber(fiber);
+        Win32FreeCoroutine(c);
+        coroutine = 0;
+    }
+    
+    return(coroutine);
+}
+
+Sys_Yield_Coroutine_Sig(system_yield_coroutine){
+    SwitchToFiber(coroutine->yield_handle);
+}
+
+
+//
+// Files
+//
+
 /*
 NOTE(casey): This follows Raymond Chen's prescription
 for fullscreen toggling, see:
@@ -1236,7 +1207,7 @@ Win32InitGL(){
         }
         
 #if (defined(BUILD_X64) && 1) || (defined(BUILD_X86) && 0)
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
         // NOTE(casey): This slows down GL but puts error messages to
         // the debug console immediately whenever you do something wrong
         glDebugMessageCallback_type *glDebugMessageCallback = 
@@ -1572,7 +1543,7 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdS
     //
     
     LPVOID base;
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
 #if defined(BUILD_X64)
     base = (LPVOID)TB(1);
 #elif defined(BUILD_X86)
@@ -1585,7 +1556,7 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdS
     memory_vars.vars_memory_size = MB(2);
     memory_vars.vars_memory = VirtualAlloc(base, memory_vars.vars_memory_size, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
     
-#if FRED_INTERNAL
+#if defined(FRED_INTERNAL)
 #if defined(BUILD_X64)
     base = (LPVOID)TB(2);
 #elif defined(BUILD_X86)
diff --git a/platform_win32/win32_threading_wrapper.h b/platform_win32/win32_threading_wrapper.h
index bbec5642..7a319aaa 100644
--- a/platform_win32/win32_threading_wrapper.h
+++ b/platform_win32/win32_threading_wrapper.h
@@ -1,7 +1,7 @@
 /*
  * Mr. 4th Dimention - Allen Webster
  *
- * 17.07.2017
+ * 18.07.2017
  *
  * Win32 threading wrapper
  *
diff --git a/run_profile.bat b/run_profile.bat
deleted file mode 100644
index 9139c688..00000000
--- a/run_profile.bat
+++ /dev/null
@@ -1,12 +0,0 @@
-@echo off
-
-SET OPTS=/W4 /wd4310 /wd4100 /wd4201 /wd4505 /wd4996 /wd4127 /wd4510 /wd4512 /wd4610 /wd4390 /WX
-SET OPTS=%OPTS% /GR- /EHa- /nologo /FC
-
-pushd ..\build
-cl %OPTS% ..\code\4ed_profile.cpp /Zi /Feprofile
-popd
-
-pushd ..\data\test
-..\..\build\profile profile.data 0.4
-popd
\ No newline at end of file