diff --git a/build.jai b/build.jai
index 9dd8a16..0c0b9ad 100644
--- a/build.jai
+++ b/build.jai
@@ -2,7 +2,7 @@
 // To generate the intermediate to see how many lines are being compiled, in x64 Native Tools Command Prompt for VS2022 or whatever
 // cl /P /EP exe_main.cpp
 // tokei exe_main.i
-VERSION :: "0.1a";
+VERSION :: "0.2";
 
 #run,stallable build_cpp_project();
 
@@ -101,7 +101,7 @@ os_target: Operating_System_Tag = .WINDOWS;
 generate_meta_file :: (debug: bool) {
     sb: String_Builder;
     append(*sb, "#pragma once\n\n");
-    print_to_builder(*sb, "constexpr const char* MUSA_LIB_VERSION = \"%\";\n", VERSION);
+    print_to_builder(*sb, "const char* MUSA_LIB_VERSION = \"%\";\n", VERSION);
     print_to_builder(*sb, "#define BUILD_DEBUG %\n", cast(s32)debug);
     
     print_to_builder(*sb, "#define OS_WINDOWS %\n", ifx os_target == .WINDOWS then 1 else 0);
diff --git a/exe_main.cpp b/exe_main.cpp
index 46540d1..909adff 100644
--- a/exe_main.cpp
+++ b/exe_main.cpp
@@ -23,6 +23,7 @@
   #include "lib/third_party/dear-imgui/imgui_impl_dx11.h"
   #include "src/ImGui_Supplementary.cpp"
   
+  #include "src/String_Analysis.cpp"
   #include "src/explorer_main.cpp"
 #endif
 
diff --git a/lib/Base/Array.h b/lib/Base/Array.h
index 8b89b89..a60d22e 100644
--- a/lib/Base/Array.h
+++ b/lib/Base/Array.h
@@ -194,6 +194,16 @@ s64 array_find (Array<T>& src, T item) {
   return -1;
 }
 
+template <typename T>
+bool array_add_if_unique (Array<T>& src, T new_item) {
+  if (array_find(src, new_item) == -1) {
+    array_add(src, new_item);
+    return true;
+  }
+  
+  return false;
+}
+
 template <typename T>
 void array_ordered_remove_by_index (Array<T>& src, s64 index) {
   Assert(index >= 0); Assert(index < src.count);
diff --git a/lib/Base/Base.h b/lib/Base/Base.h
index 4d9793b..ec4a377 100644
--- a/lib/Base/Base.h
+++ b/lib/Base/Base.h
@@ -3,6 +3,9 @@
 #define LANG_CPP 1
 #define BUILD_CONSOLE_INTERFACE BUILD_DEBUG
 
+#include <stdio.h> // vsnprintf
+#include <cstdarg> // va_list, ...
+
 #if ARCH_CPU_X64
   #include "CPU_X64.cpp"
   #define PLATFORM_MEMORY_PAGE_SIZE 4096
@@ -13,15 +16,12 @@
   #error "CPU not supported (yet)!"
 #endif
 
-#include <stdio.h> // vsnprintf
-#include <cstdarg> // va_list, ...
-
-
 #if OS_WINDOWS
   #define WIN32_LEAN_AND_MEAN
   #include <Windows.h>
   #undef ERROR // why...
   #undef NO_ERROR // ugh...
+  #include <winioctl.h>
 #else
   #error "This configuration is NOT supported. Only Windows with MSVC is currently supported."
 #endif
diff --git a/lib/Base/CPU_X64.cpp b/lib/Base/CPU_X64.cpp
index 6a09f2c..63d8c2b 100644
--- a/lib/Base/CPU_X64.cpp
+++ b/lib/Base/CPU_X64.cpp
@@ -1,11 +1,21 @@
 #if OS_WINDOWS
 #include <intrin.h>
 
+int cpu_max_feature_leaf () {
+  int cpuInfo[4];
+
+  __cpuid(cpuInfo, 0);
+  int maxLeaf = cpuInfo[0];
+
+  return maxLeaf;
+}
+
 int CPU_Base_Frequency() {
   int cpuInfo[4] = {0};
     
   // Call CPUID with EAX = 0x16 (Base CPU Frequency)
-  __cpuid(cpuInfo, 0x16);
+  if (cpu_max_feature_leaf() >= 0x16)
+    __cpuid(cpuInfo, 0x16);
   
   return cpuInfo[0];
 }
diff --git a/lib/Base/ErrorType.cpp b/lib/Base/ErrorType.cpp
index a94fe18..47c3d68 100644
--- a/lib/Base/ErrorType.cpp
+++ b/lib/Base/ErrorType.cpp
@@ -4,7 +4,8 @@ enum class ErrorClass: s32 {
   NONE      = 0, // should not be used, just to avoid a default value being assigned.
   WARNING   = 1,
   ERROR     = 2,
-  FATAL     = 3
+  FATAL     = 3,
+  TODO      = 4,
 };
 
 // #downcasts to string
@@ -38,6 +39,10 @@ char* error_severity (ErrorClass severity) {
     case ErrorClass::FATAL:   {
       return "[FATAL ERROR]";
     } break;
+    case ErrorClass::TODO:   {
+      return "[TODO]";
+    } break;
+    
   }
   return "";
 }
@@ -48,6 +53,9 @@ string to_string (Error* error) {
   return { error->count, error->data };
 }
 
+#define log_todo(fmt, ...) \
+    Log_Error_2(__FILE__, __FUNCTION__, __LINE__, ErrorClass::TODO, fmt, ##__VA_ARGS__)
+
 #define log_fatal_error(fmt, ...) \
     Log_Error_2(__FILE__, __FUNCTION__, __LINE__, ErrorClass::FATAL, fmt, ##__VA_ARGS__)
 
@@ -136,6 +144,7 @@ void push_error (Thread_Context* tctx, Error* new_error) {
   tctx->current_error = new_error;
   
   switch (new_error->severity) {
+    case ErrorClass::TODO:
     case ErrorClass::NONE:
     case ErrorClass::WARNING: {
       print(to_string(new_error));
diff --git a/lib/Base/Unicode.cpp b/lib/Base/Unicode.cpp
new file mode 100644
index 0000000..c9b5ffe
--- /dev/null
+++ b/lib/Base/Unicode.cpp
@@ -0,0 +1,52 @@
+constexpr u8 trailing_bytes_for_utf8[] = {
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+	1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+	2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5};
+constexpr u32 UNI_REPLACEMENT_CHAR = 0x0000FFFD;
+constexpr u8 utf8_inital_byte_mask[6] = { 0x7F, 0x1F, 0x0F, 0x07, 0x03, 0x01 };
+constexpr u32 UNI_MAX_UTF32        = 0x7FFFFFFF;
+
+bool character_utf8_to_utf32 (u8* data, s64 source_length, u32* utf32, s64* source_length_out) {
+  u8 first_character = data[0];
+  s32 continuation_bytes = trailing_bytes_for_utf8[first_character];
+  
+  if ((continuation_bytes + 1) > source_length) {
+    (*utf32) = UNI_REPLACEMENT_CHAR;
+    (*source_length_out) = source_length;
+    return false;
+  }
+  
+  u32 ch = data[0] & utf8_inital_byte_mask[continuation_bytes];
+  
+  for (s64 i = 1; i < continuation_bytes + 1; i += 1) {
+    ch = ch << 6;
+    //if strict ...
+    ch |= data[i] & 0x3F;
+  }
+  
+  // #if strict... {}
+  (*utf32) = ch;
+  (*source_length_out) = continuation_bytes + 1;
+  
+  if (ch > UNI_MAX_UTF32) {
+    (*utf32) = UNI_REPLACEMENT_CHAR;
+  }
+  
+  return true;
+}
+
+bool next_utf8_to_utf32 (string& s, u32* utf32_char_out) {
+  s64 codepoint_source_length;
+  bool success = character_utf8_to_utf32(s.data, s.count, utf32_char_out, &codepoint_source_length);
+  
+  s.data  += codepoint_source_length;
+  s.count -= codepoint_source_length;
+  
+  Assert(s.count >= 0);
+  return success;
+}
diff --git a/lib/Base/run_tests.cpp b/lib/Base/run_tests.cpp
index cb0124c..95301c3 100644
--- a/lib/Base/run_tests.cpp
+++ b/lib/Base/run_tests.cpp
@@ -1,5 +1,5 @@
 void run_pre_setup_tests() {
-   // #no_context: context will not be initialized at this point.
+  // #no_context: context will not be initialized at this point, so log() doesn't work
   printf("Running pre-setup tests...\n");
   printf("\nFinished running pre-setup tests...\n");
 }
diff --git a/lib/OS/OS_Win32.cpp b/lib/OS/OS_Win32.cpp
index 41a7af1..52e1726 100644
--- a/lib/OS/OS_Win32.cpp
+++ b/lib/OS/OS_Win32.cpp
@@ -1,8 +1,9 @@
 // #TODO: #OS_Win32
 // [ ] #Exception handling code in `Win32_Exception_Filter`
 // [~] #Thread cleanup: in `thread_deinit` is there any requirement to cleanup child threads?
-  // - I think no? Threads should handle their own lifetimes, and the parent threads should ensure child threads are complete
+  // - I think: no? Threads should handle their own lifetimes, and the parent threads should ensure child threads are complete
   // before terminating.
+  // Or we can move child threads up to the parent?
 
 constexpr s64 FILETIME_TO_UNIX = 116444736000000000i64;
 f64 GetUnixTimestamp () {
@@ -34,7 +35,7 @@ string format_time_datetime (FILETIME ft) {
   SYSTEMTIME stUTC, st;
   FileTimeToSystemTime(&ft, &stUTC);
   SystemTimeToTzSpecificLocalTime(nullptr, &stUTC, &st);
-  // YYYY-MM-DD-
+  
   return format_string("%04u-%02u-%02u %02u:%02u:%02u.%03u",
              st.wYear,
              st.wMonth,
@@ -252,7 +253,6 @@ internal void Win32_Entry_Point (int argc, WCHAR **argv) {
   // [ ] Get Working directory (info->working_path)
   // [ ] GetEnvironmentStringsW
   temp_reset();
-  printf("Hello there!\n\n");
 }
 
 C_LINKAGE DWORD OS_Windows_Thread_Entry_Point (void* parameter) {
@@ -1147,6 +1147,14 @@ void init (STFE_Results* results) {
   results->modtimes = arena_array_new<u64>(1024*1024*4, Arena_Reserve::Size_2G);
 }
 
+void STFE_Results_Free (STFE_Results* results) {
+  arena_array_free(*results->strings);
+  arena_array_free(*results->offsets);
+  arena_array_free(*results->lengths);
+  arena_array_free(*results->sizes);
+  arena_array_free(*results->modtimes);
+}
+
 struct ST_File_Enumeration { // global state
   ArrayView<OS_Drive*> drives;
   Thread* master_thread;
@@ -1163,6 +1171,20 @@ struct ST_File_Enumeration { // global state
 
 global ST_File_Enumeration* stfe;
 
+void free_stfe_and_reset () {
+  push_allocator(GPAllocator());
+  
+  array_free(stfe->drives);
+  
+  internal_free(stfe->master_thread);
+  
+  STFE_Results_Free(&stfe->dirs);
+  STFE_Results_Free(&stfe->files);
+  
+  internal_free(stfe);
+  stfe = nullptr; // final step
+}
+
 string add_record (ST_File_Enumeration* stfe, string full_path, bool is_directory, WIN32_FIND_DATAW* find_data) {
   // return the string copy!
   if (is_directory) {
@@ -1257,7 +1279,8 @@ s64 win32_file_enum_thread_proc (Thread* thread) {
   init(&task->dirs);
   init(&task->files);
   
-  // while files available?
+  // Allocates to thread_context->arena, which is cleaned up 
+  // when the thread completes. see: thread_deinit
   Array<string> paths_to_enumerate;
   
   for_each(d, task->drives) {
@@ -1441,7 +1464,6 @@ void Win32_Enable_USN_Journal_Monitoring (ArrayView<OS_Drive*> drives) {
   }
 }
 
-#include <winioctl.h>
 void Query_USN_Journal (ArrayView<OS_Drive*> drives) {
   Win32_Enable_USN_Journal_Monitoring(drives);
   for_each(d, drives) {
diff --git a/lib/OS/OS_Win32_File_Enumeration.cpp b/lib/OS/OS_Win32_File_Enumeration.cpp
new file mode 100644
index 0000000..1897674
--- /dev/null
+++ b/lib/OS/OS_Win32_File_Enumeration.cpp
@@ -0,0 +1,334 @@
+struct Parent_Index {
+  s32 thread_index; // group->worker_info[thread_index].thread
+  s32 parent_index; // index into d_*offsets/lengths/etc.
+};
+
+struct File_Enumeration_Thread_Results { // #userdata
+  Arena* arena; // for strings
+  // Directories
+  ArenaArray<u32>*  d_offsets;
+  ArenaArray<s16>*  d_lengths;
+  ArenaArray<Parent_Index>*  d_parent_indices;
+  ArenaArray<u64>*  d_modtime;
+  // s64 dirs_enumerated = 0;
+  // Files
+  ArenaArray<u32>*  f_offsets;
+  ArenaArray<s16>*  f_lengths;
+  ArenaArray<Parent_Index>*  f_parent_indices;
+  ArenaArray<u64>*  f_sizes;
+  ArenaArray<u64>*  f_modtime;
+};
+
+void initialize (File_Enumeration_Thread_Results* fcr) { // Preallocate for 2^22 files:
+  fcr->arena            = next_arena(Arena_Reserve::Size_2G);
+
+  fcr->d_offsets        = arena_array_new<u32>(4194304, Arena_Reserve::Size_2G);
+  fcr->d_lengths        = arena_array_new<s16>(4194304, Arena_Reserve::Size_2G);
+  fcr->d_parent_indices = arena_array_new<Parent_Index>(4194304, Arena_Reserve::Size_2G);
+  fcr->d_modtime        = arena_array_new<u64>(4194304, Arena_Reserve::Size_2G);
+  
+  fcr->f_offsets        = arena_array_new<u32>(4194304, Arena_Reserve::Size_2G);
+  fcr->f_lengths        = arena_array_new<s16>(4194304, Arena_Reserve::Size_2G);
+  fcr->f_parent_indices = arena_array_new<Parent_Index>(4194304, Arena_Reserve::Size_2G);
+  fcr->f_sizes          = arena_array_new<u64>(4194304, Arena_Reserve::Size_2G);
+  fcr->f_modtime        = arena_array_new<u64>(4194304, Arena_Reserve::Size_2G);
+}
+
+struct Enumeration_Work {
+  string first_directory;
+  Parent_Index parent;
+  bool is_root = false;
+  Array<Enumeration_Work*> next;
+};
+
+struct Drive_Enumeration { // master thread struct
+  ArrayView<OS_Drive*> drives;
+  Thread* master_thread;
+  
+  s32 thread_count;
+  bool thread_started;
+  bool thread_completed;
+  
+  // Files_Combined_Results paths;
+  // Files_Combined_Results files;
+  
+  s32 work_added = 0;
+  s32 work_completed = 0;
+};
+
+// void push_root (Drive_Enumeration* de, string label, s32 index) {
+//   array_add(*de->paths.name, label);
+//   array_add(*de->paths.parent_indices, index);
+//   array_add(*de->paths.sizes, (u64)0);
+//   array_add(*de->paths.modtime, (u64)0);
+// }
+
+global Drive_Enumeration* drive_enumeration;
+
+// File_Enumeration_Thread_Results* results_from_thread_index (Thread_Group* group, s32 thread_index) {
+//   return ;
+// }
+
+string path_from_parent_index (Thread_Group* group, Parent_Index pid, Parent_Index* next_pid) {
+  if (pid.parent_index == -1) return "";
+
+  auto results = (File_Enumeration_Thread_Results*)group->worker_info[pid.thread_index].thread.context->userdata;
+  u8* offset = (results->arena->memory_base + (*results->d_offsets)[pid.parent_index]);
+  u32 length = (*results->d_lengths)[pid.parent_index];
+  
+  (*next_pid) = (*results->d_parent_indices)[pid.parent_index];
+  
+  return {(s64)length, offset};
+}
+
+// This is much stupider and more complicated than I would like, unfortunately.
+string directory_get_full_path (Thread_Group* group, Parent_Index pid, string dir_name) {
+  push_allocator(GPAllocator()); // to copy from String_Builder
+
+  Array<string> paths;
+  paths.allocator = temp();
+  
+  Parent_Index this_pid = pid;
+  Parent_Index next_pid = {};
+  string parent_dir = path_from_parent_index(group, this_pid, &next_pid);
+  array_add(paths, parent_dir);
+  
+  this_pid = next_pid;
+  next_pid = {};
+  
+  while (this_pid.parent_index != -1) {
+    parent_dir = path_from_parent_index(group, this_pid, &next_pid);
+    array_add(paths, parent_dir);
+    
+    this_pid = next_pid;
+    next_pid = {};
+  }
+  
+  // go in reverse order and add together string
+  String_Builder* sb = new_string_builder(Arena_Reserve::Size_64K);
+  for (s64 i = paths.count-1; i >= 0; i -= 1) {
+    append(sb, paths[i]);
+    append(sb, "\\");
+  }
+  append(sb, dir_name);
+  
+  return builder_to_string(sb);
+}
+
+/*void update_results (Drive_Enumeration* de, Enumeration_Work* ew) {
+  // merge results and release resources!
+  // unfortunately this is a LOT of copying!
+  for_each(i, (*ew->d_offsets)) {
+    u8* string_ptr = (ew->thread_arena->memory_base + (*ew->d_offsets)[i]);
+    string name = {(*ew->d_lengths)[i], string_ptr};
+    array_add(*de->paths.name,           name);
+    array_add(*de->paths.parent_indices, (*ew->d_parent_indices)[i]);
+    array_add(*de->paths.sizes,          (*ew->d_sizes)[i]);
+    array_add(*de->paths.modtime,        (*ew->d_modtime)[i]);
+  }
+  for_each(i, (*ew->offsets)) {
+    u8* string_ptr = (ew->thread_arena->memory_base + (*ew->offsets)[i]);
+    string name = {(*ew->lengths)[i], string_ptr};
+    array_add(*de->files.name,           name);
+    array_add(*de->files.parent_indices, (*ew->parent_indices)[i]);
+    array_add(*de->files.sizes,          (*ew->sizes)[i]);
+    array_add(*de->files.modtime,        (*ew->modtime)[i]);
+  }
+}*/
+
+void add_record (File_Enumeration_Thread_Results* results, 
+                 WIN32_FIND_DATAW* find_data, 
+                 string name, 
+                 Parent_Index parent_index, 
+                 bool is_directory) {
+  u32 offset = (u32)(name.data - results->arena->memory_base);
+  u64 size = ((u64)find_data->nFileSizeHigh << 32) | ((u64)find_data->nFileSizeLow & 0xFFFFFFFF);
+  u64 modtime = FILETIME_to_ticks(find_data->ftLastWriteTime);
+  
+  if (is_directory) {
+    array_add((*results->d_offsets), offset);
+    array_add((*results->d_lengths), (s16)name.count);
+    array_add((*results->d_parent_indices), parent_index); // #parent_index
+    array_add((*results->d_modtime), modtime);
+  } else {
+    array_add((*results->f_offsets), offset);
+    array_add((*results->f_lengths), (s16)name.count);
+    array_add((*results->f_parent_indices), parent_index); // #parent_index
+    array_add((*results->f_sizes), size);
+    array_add((*results->f_modtime), modtime);
+  }
+}
+
+Thread_Continue_Status file_enumeration_thread_group_proc (Thread_Group* group, Thread* thread, void* work) {
+  // 1. setup userdata as an Arena*:
+  // #TODO: replace userdata with a struct that manages the thread-local data for this 
+  // particular problem. This data can be rescued before we 
+  File_Enumeration_Thread_Results* results;
+  if (!thread->context->userdata) {
+    thread->context->userdata = New<File_Enumeration_Thread_Results>(GPAllocator());
+    initialize((File_Enumeration_Thread_Results*)thread->context->userdata);
+  }
+  results = (File_Enumeration_Thread_Results*)thread->context->userdata;
+  
+  Enumeration_Work* enum_work = (Enumeration_Work*)work;
+  
+  // Validate thread context?
+  push_allocator(temp());
+  auto_release_temp();
+  
+  // log("file_enumeration_thread_group_proc, thread index: %d", thread->index);
+  
+  // MAKE SURE PATH IS NULL TERMINATED!
+  wstring wildcard_name = utf8_to_wide(format_string("%s\\*", enum_work->first_directory.data)); // #temp
+  WIN32_FIND_DATAW find_data;
+  HANDLE h = FindFirstFileExW((LPCWSTR)wildcard_name.data, FindExInfoBasic, &find_data, 
+                FindExSearchNameMatch, nullptr, FIND_FIRST_EX_LARGE_FETCH);
+  if (h == INVALID_HANDLE_VALUE) {
+    return Thread_Continue_Status::CONTINUE;
+  }
+  
+  s32 thread_index = get_thread_index(group, (s32)thread->index); // zero-indexed to thread group
+  
+  Parent_Index pi = enum_work->parent;
+  
+  push_arena(results->arena);
+  if (enum_work->is_root) { // see add_record
+    string name = copy_string(enum_work->first_directory);
+    u32 offset = (u32)(name.data - results->arena->memory_base);
+    s32 current_index = (s32)(*results->d_offsets).count;
+    pi = {thread_index, current_index};
+    array_add((*results->d_offsets), offset);
+    array_add((*results->d_lengths), (s16)name.count);
+    Parent_Index root_pi = {thread_index, -1};
+    array_add((*results->d_parent_indices), root_pi); // #parent_index
+    array_add((*results->d_modtime), (u64)0);
+    // results->dirs_enumerated += 1;
+  }
+    
+  while (true) {
+    string name = wide_to_utf8((u16*)find_data.cFileName);
+    bool should_continue = (name.count == 0 || name == "." || name == "..");
+    if (should_continue) {
+      bool success = FindNextFileW(h, &find_data);
+      if (!success) 
+        break;
+      continue;
+    }
+
+    bool is_directory = (find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
+    Parent_Index next_index = {thread_index, enum_work->parent.parent_index};
+    add_record(results, &find_data, name, next_index, is_directory);
+    
+    if (is_directory) {
+      push_allocator(GPAllocator());
+      auto new_work = New<Enumeration_Work>(false);
+      new_work->first_directory = directory_get_full_path(group, pi, name);
+      new_work->parent = next_index;
+      new_work->is_root = false;
+      new_work->next = {};
+      
+      array_add(enum_work->next, new_work);
+    }
+    
+    bool success = FindNextFileW(h, &find_data);
+    if (!success) break;
+  }
+  
+  FindClose(h);
+  return Thread_Continue_Status::CONTINUE;
+}
+
+s64 multithreaded_file_enumeration_master_proc (Thread* thread) {
+  auto task = thread_task(Drive_Enumeration);
+  
+  Thread_Group* file_enum_thread_group = New<Thread_Group>();
+  
+  s32 thread_count = os_cpu_physical_core_count();
+  
+  push_allocator(GPAllocator());
+  thread_group_init(file_enum_thread_group, thread_count, file_enumeration_thread_group_proc, true);
+  
+  
+  for_each(d, task->drives) {
+    auto work = New<Enumeration_Work>(GPAllocator(), false); //replace with arena bootstrap?
+    work->first_directory = task->drives[d]->label; // this includes the colon-slash, (e.g. `C:\`).
+    work->parent = {-1, -1}; // #HACK: (s32)d
+    work->is_root = true;
+    work->next = {};
+    
+    add_work(file_enum_thread_group, work);
+    task->work_added += 1;
+  }
+  
+  start(file_enum_thread_group);
+  // set task completed.
+  
+  s64 path_index = task->drives.count;
+  
+  while (true) {
+    auto_release_temp();
+    ArrayView<void*> cw = get_completed_work(file_enum_thread_group);
+    task->work_completed += (s32)cw.count;
+    for_each(i, cw) {
+      auto ew = (Enumeration_Work*)cw[i];
+      
+      for_each(w, ew->next) {
+        auto new_work = ew->next[w];
+        
+        add_work(file_enum_thread_group, new_work);
+      }
+      task->work_added += (s32)ew->next.count;
+      
+      string_free(ew->first_directory);
+      array_free(ew->next);
+      internal_free(ew);
+    }
+    
+    log("work completed: %d/%d",task->work_completed, task->work_added);
+    // if (task->work_completed >= task->work_added) break;
+    Sleep(1);
+  }
+  
+  shutdown(file_enum_thread_group);
+  
+  task->thread_completed = true;
+  return 0;
+}
+
+void os_run_file_enumeration_multithreaded () {
+  // Need some struct to track the state of this operation.
+  drive_enumeration = New<Drive_Enumeration>();
+  (*drive_enumeration) = {
+    os_get_available_drives(), 
+    New<Thread>(),
+    os_cpu_physical_core_count(), 
+    0, 0, 0, 0
+  };
+  
+  // initialize(&drive_enumeration->paths);
+  // initialize(&drive_enumeration->files);
+  
+  // We start 1 thread to run the thread group and track the threads
+  string thread_name = "Multithreaded Enumeration: Master Thread";
+  bool success = thread_init(drive_enumeration->master_thread, 
+          multithreaded_file_enumeration_master_proc, thread_name);
+  Assert(success);
+  thread_start(drive_enumeration->master_thread, drive_enumeration);
+  drive_enumeration->thread_started = true;
+}
+
+bool file_enum_multithreading_started () {
+  if (drive_enumeration == nullptr) return false;
+  return drive_enumeration->thread_started;
+}
+
+bool file_enum_multithreading_active () {
+  if (drive_enumeration == nullptr) return false;
+  if (drive_enumeration->thread_completed) {
+    return false;
+  }
+  if (drive_enumeration->thread_started) {
+    return true;
+  }
+  return false;
+}
diff --git a/lib/OS/OS_Win32_NTFS.cpp b/lib/OS/OS_Win32_NTFS.cpp
index bdbc501..ce1d80f 100644
--- a/lib/OS/OS_Win32_NTFS.cpp
+++ b/lib/OS/OS_Win32_NTFS.cpp
@@ -63,7 +63,7 @@ struct NTFS_ResidentAttributeHeader : NTFS_AttributeHeader {
 };
 
 struct NTFS_FileNameAttributeHeader : NTFS_ResidentAttributeHeader {
-    u64    parentRecordNumber : 48;
+    u64    parentRecordNumber : 48; // low 48 bits
     u64    sequenceNumber : 16;
     u64    creationTime;
     u64    modificationTime;
@@ -585,8 +585,32 @@ bool Serialize_Win32_Drives (ArrayView<Win32_Drive*> drives, string file_path) {
   return true;
 }
 
+void ntfs_create_enumeration_threads (s32 thread_count) {
+  if (!ex1_ntfs.initialized) { Timed_Block_Print("Thread initialization (ntfs)");
+    ex1_ntfs.initialized = true;
+    ex1_ntfs.threads = ArrayView<Thread>(thread_count);
+    ex1_ntfs.threads_in_flight.allocator = GPAllocator();
+    for_each(t, ex1_ntfs.threads) {
+      string thread_name = format_string("ntfs_enumeration_thread#%d", t);
+      bool success = thread_init(&ex1_ntfs.threads[t], ntfs_enumeration_thread_proc, thread_name);
+      Assert(success);
+    }
+  }
+}
+
+
 /*
 void Ex1_show_ntfs_workspace () { using namespace ImGui;
+
+  SliderInt("Select path index", &ex1w.path_select, 0, count_paths(stfe)-1);
+  Text("%s", get_path_copy(stfe, ex1w.path_select).data);
+  Text("time modified: %s", format_time_datetime(get_path_modtime(stfe, ex1w.path_select)).data);
+  // #TODO: modtime (to indextime)
+  SliderInt("Select file index", &ex1w.file_select, 0, count_files(stfe)-1);
+  Text("%s", get_file_copy(stfe, ex1w.file_select).data);
+  Text("size: %s", format_bytes(get_file_size_bytes(stfe, ex1w.file_select)).data);
+  Text("time modified: %s", format_time_datetime(get_file_modtime(stfe, ex1w.file_select)).data);
+  
   push_allocator(temp());
   for_each(d, ntfs_workspace.drives) {
     OS_Drive* drive = ntfs_workspace.drives[d];
@@ -633,4 +657,111 @@ void Ex1_show_ntfs_workspace () { using namespace ImGui;
     }
   }
 }
-*/
\ No newline at end of file
+*/
+  /*SeparatorText("ex1_ntfs");
+  Text("Threads in flight count: %d", ex1_ntfs.threads_in_flight.count);
+  for_each(i, ex1_ntfs.threads) {
+    Text(" [%d] initialized: %d, has_context: %d, has_data: %d", 
+      i, ex1_ntfs.threads[i].proc != nullptr, ex1_ntfs.threads[i].context != nullptr, ex1_ntfs.threads[i].data != nullptr);
+  }*/
+  /*// #NTFS_MFT_RAW
+    push_allocator(GPAllocator());
+    Array<ArrayView<OS_Drive*>> drive_split;
+    drive_split.allocator = temp(); // this is only needed for this frame
+
+    if (drives.count > os_cpu_physical_core_count()) {
+      s32 thread_count = os_cpu_physical_core_count();
+      array_resize(drive_split, thread_count);
+      ntfs_create_enumeration_threads(thread_count);
+      
+      s32 threads_to_create = thread_count;
+      s64 drives_per_thread = (drives.count / thread_count);
+      s64 remainder = drives.count % thread_count;
+      s64 current_drive = 0;
+      
+      for_each(d, drive_split) {
+        if (d == drive_split.count) {
+          drive_split[d] = ArrayView<OS_Drive*>(remainder);
+        } else {
+          drive_split[d] = ArrayView<OS_Drive*>(drives_per_thread);
+        }
+        
+        for (s64 i = 0; i < drive_split[d].count; i += 1) {
+          drive_split[d][i] = drives[current_drive];
+          current_drive += 1;
+        }
+      }
+      
+      debug_break(); // #TODO: Check that the work has been distributed correctly.
+    } else { // more threads than drives, or same amount
+      s32 thread_count = (s32)drives.count;
+      array_resize(drive_split, drives.count);
+      ntfs_create_enumeration_threads(thread_count);
+      
+      for_each(d, drives) {
+        auto drive = drives[d];
+        drive_split[d] = ArrayView<OS_Drive*>(1); // Arrays of size one are sad :pensive:
+        
+        drive_split[d][0] = drive;
+      }
+    }
+    
+    s64 active_thread_count = drive_split.count;
+    
+    ex1_ntfs.threads_started = true;
+    for (s64 t = 0; t < active_thread_count; t += 1) {
+      Thread* thread = &ex1_ntfs.threads[t];
+      Arena* thread_arena = next_arena(Arena_Reserve::Size_64K);
+      push_arena(thread_arena);
+      auto thread_data = New<NTFS_Enumeration_Task>();
+        thread_data->pool = thread_arena;
+        thread_data->drives = drive_split[t];
+      thread_start(thread, thread_data);
+      array_add(ex1_ntfs.threads_in_flight, thread);
+    }*/
+  
+  
+  /* #NTFS_MFT_RAW
+  if (ex1_ntfs.threads_in_flight.count) {
+    Text("Threads in flight: %d", ex1_ntfs.threads_in_flight.count);
+
+    for_each(t, ex1_ntfs.threads_in_flight) {
+      if (thread_is_done(ex1_ntfs.threads_in_flight[t])) {
+        push_allocator(GPAllocator());
+        
+        Thread* thread = ex1_ntfs.threads_in_flight[t];
+        auto task = thread_task(NTFS_Enumeration_Task);
+        array_free(task->drives);
+
+        // make sure to retreive any data you need to from here!
+        release_arena(task->pool);
+        
+        thread_deinit(ex1_ntfs.threads_in_flight[t], false);
+        array_unordered_remove_by_index(ex1_ntfs.threads_in_flight, t);
+        t -= 1; // check this element index again!
+      }
+    }
+  }*/
+  
+  /* #NTFS_MFT_RAW
+  if (ex1_ntfs.threads_started && !ex1_ntfs.threads_in_flight.count) {
+    // All threads are complete, we're free to clean up remaining memory
+    push_allocator(GPAllocator());
+    array_free(ex1_ntfs.threads);
+    array_free(ex1_ntfs.threads_in_flight);
+    
+    // Instead maybe we should just memset this to zero.
+    reset_struct(&ex1_ntfs);
+  }
+  
+  // How do I tell when all files are enumerated?
+  // check drives[i]->data.paths.wstrings.count count?
+  if (all_drives_enumerated && Button("Save drive data")) {
+    string file_path = format_string_temp("%s_DriveData.bin", os_get_machine_name().data);
+    bool success = Serialize_Win32_Drives(drives, file_path);
+    if (!success) { log_error("Failed to save Win32_Drive data"); }
+  }
+  
+  if (all_drives_enumerated && Button("Clear all drive data")) {
+    os_clear_drive_data();
+  }*/
diff --git a/lib/meta_generated.h b/lib/meta_generated.h
index d2c1210..700a5eb 100644
--- a/lib/meta_generated.h
+++ b/lib/meta_generated.h
@@ -1,6 +1,6 @@
 #pragma once
 
-constexpr const char* MUSA_LIB_VERSION = "0.1a";
+const char* MUSA_LIB_VERSION = "0.2";
 #define BUILD_DEBUG 1
 #define OS_WINDOWS 1
 #define OS_LINUX 0
diff --git a/lib_main.cpp b/lib_main.cpp
index 1339ec2..0b2d8f6 100644
--- a/lib_main.cpp
+++ b/lib_main.cpp
@@ -36,6 +36,7 @@
 
 #include "lib/Base/Arena.cpp"
 #include "lib/Base/String.cpp"
+#include "lib/Base/Unicode.cpp"
 #include "lib/Base/RadixSort.cpp"
 
 #include "lib/Base/Base_Thread_Context.cpp"
@@ -53,7 +54,7 @@
 
 #if OS_WINDOWS 
 # include "lib/OS/OS_Win32.cpp"
-# include "lib/OS/OS_Win32_NTFS.cpp"
+// # include "lib/OS/OS_Win32_NTFS.cpp"
 #endif
 
 #include "lib/Graphics.cpp"
diff --git a/src/Base_Entry_Point.cpp b/src/Base_Entry_Point.cpp
index fd98655..3bd25ae 100644
--- a/src/Base_Entry_Point.cpp
+++ b/src/Base_Entry_Point.cpp
@@ -17,7 +17,9 @@ internal void Main_Entry_Point (int argc, WCHAR **argv);
 #endif
 
 internal void Main_Entry_Point (int argc, WCHAR **argv) { // #entry_point
-  set_cpu_base_frequency(4000); // REQUIRED FOR TIMING MODULE! will depend on CPU
+  // #TODO: Check if base frequency is even available.
+  u32 base_frequency = (u32)CPU_Base_Frequency();
+  set_cpu_base_frequency(base_frequency); // REQUIRED FOR TIMING MODULE! will depend on CPU
   
 #if BASE_RUN_TESTS
   run_pre_setup_tests(); // #no_context: context will not be initialized at this point.
diff --git a/src/Ex1.cpp b/src/Ex1.cpp
index 716fc80..19ef3a7 100644
--- a/src/Ex1.cpp
+++ b/src/Ex1.cpp
@@ -22,19 +22,6 @@ global ExplorerUI explorer_ui;
 global Explorer explorer;
 global Ex1_NTFS_Enumeration ex1_ntfs;
 
-void ntfs_create_enumeration_threads (s32 thread_count) {
-  if (!ex1_ntfs.initialized) { Timed_Block_Print("Thread initialization (ntfs)");
-    ex1_ntfs.initialized = true;
-    ex1_ntfs.threads = ArrayView<Thread>(thread_count);
-    ex1_ntfs.threads_in_flight.allocator = GPAllocator();
-    for_each(t, ex1_ntfs.threads) {
-      string thread_name = format_string("ntfs_enumeration_thread#%d", t);
-      bool success = thread_init(&ex1_ntfs.threads[t], ntfs_enumeration_thread_proc, thread_name);
-      Assert(success);
-    }
-  }
-}
-
 #define HOTKEY_ID_BRING_TO_FOREGROUND 1
 #define VK_SPACE_KEY_CODE 0x20
 // #define HOTKEY_ID_HIDE_TITLEBAR
@@ -91,6 +78,23 @@ struct Ex1_Workspace {
   ArrayView<string> files_sorted_by_modtime;
 };
 
+global Ex1_Workspace ex1w;
+
+void free_ex1_workspace_and_reset () {
+  if (ex1w.sort_completed) {
+    push_allocator(GPAllocator());
+    
+    radix_sort_free(&ex1w.file_size_radix);
+    radix_sort_free(&ex1w.file_modtime_radix);
+    radix_sort_free(&ex1w.dir_modtime_radix);
+    
+    array_free(ex1w.files_sorted_by_size);
+    array_free(ex1w.files_sorted_by_modtime);
+    
+    zero_struct(&ex1w);
+  }
+}
+
 // #TODO: Move all sort stuff to OS_Win32?
 // Make a general version of this that takes two ArrayView<T> and reorders.
 void os_win32_reorder_files_by_radix (RadixSort* r, ArrayView<string>* files, bool reverse_order=false) {
@@ -103,24 +107,10 @@ void os_win32_reorder_files_by_radix (RadixSort* r, ArrayView<string>* files, bo
   }
 }
 
-global Ex1_Workspace ex1w;
-
 void Ex1_show_enumeration_workspace () { using namespace ImGui;
   push_imgui_window("Enumerated Data Workspace");
 
-  /*
-  SliderInt("Select path index", &ex1w.path_select, 0, count_paths(stfe)-1);
-  Text("%s", get_path_copy(stfe, ex1w.path_select).data);
-  Text("time modified: %s", format_time_datetime(get_path_modtime(stfe, ex1w.path_select)).data);
-  // #TODO: modtime (to indextime)
-  SliderInt("Select file index", &ex1w.file_select, 0, count_files(stfe)-1);
-  Text("%s", get_file_copy(stfe, ex1w.file_select).data);
-  Text("size: %s", format_bytes(get_file_size_bytes(stfe, ex1w.file_select)).data);
-  Text("time modified: %s", format_time_datetime(get_file_modtime(stfe, ex1w.file_select)).data);
-  */
-  // #TODO: size, modtime
-  
-  if (!ex1w.sort_completed || Button("sort file sizes")) {
+  if (!ex1w.sort_completed) {
     push_allocator(GPAllocator());
     Timed_Block_Print("radix_sort_u64: file sizes, file modtimes, directory modtimes");
     ArrayView<u64> sizes = to_view(*stfe->files.sizes);
@@ -136,24 +126,43 @@ void Ex1_show_enumeration_workspace () { using namespace ImGui;
     ex1w.sort_completed = true;
   }
   
-  if (ex1w.sort_completed) {
-    SeparatorText("Files ordered by modtime");
-    s32 file_count = (s32)ex1w.files_sorted_by_modtime.count;
-    SliderInt("Select file index", &ex1w.file_select, 0, file_count-1);
-    string file_name = copy_string(ex1w.files_sorted_by_modtime[ex1w.file_select]);
-    Text("%s", file_name.data);
-    u32 radix_index = rank(&ex1w.file_modtime_radix, ex1w.file_select);
-    Text("date modified: %s", format_time_datetime(get_file_modtime(stfe, radix_index)).data);
+  if (!ex1w.sort_completed) { return; }
+  
+  SeparatorText("Files ordered by modtime");
+  s32 file_count = (s32)ex1w.files_sorted_by_modtime.count;
+  SliderInt("Select file index", &ex1w.file_select, 0, file_count-1);
+  string file_name = copy_string(ex1w.files_sorted_by_modtime[ex1w.file_select]);
+  Text("%s", file_name.data);
+  u32 radix_index = rank(&ex1w.file_modtime_radix, ex1w.file_select);
+  Text("date modified: %s", format_time_datetime(get_file_modtime(stfe, radix_index)).data);
+
+  SeparatorText("Files ordered by size");
+  file_count = (s32)ex1w.files_sorted_by_size.count;
+  // SliderInt("Select file index", &ex1w.file_select, 0, file_count-1);
+  file_name = copy_string(ex1w.files_sorted_by_size[ex1w.file_select]);
+  Text("%s", file_name.data);
+  radix_index = rank(&ex1w.file_size_radix, ex1w.file_select);
+  Text("size: %s", format_bytes(get_file_size_bytes(stfe, radix_index)).data);
+  // Text("date modified: %s", format_time_datetime(get_file_modtime(stfe, radix_index)).data);
+    
+  if (Button("Count unique UTF-8 characters")) {
+    count_unique_utf8_chars();
   }
-  if (ex1w.sort_completed) {
-    SeparatorText("Files ordered by size");
-    s32 file_count = (s32)ex1w.files_sorted_by_size.count;
-    // SliderInt("Select file index", &ex1w.file_select, 0, file_count-1);
-    string file_name = copy_string(ex1w.files_sorted_by_size[ex1w.file_select]);
-    Text("%s", file_name.data);
-    u32 radix_index = rank(&ex1w.file_size_radix, ex1w.file_select);
-    Text("size: %s", format_bytes(get_file_size_bytes(stfe, radix_index)).data);
-    // Text("date modified: %s", format_time_datetime(get_file_modtime(stfe, radix_index)).data);
+  
+  Text("unique_codepoints_utf32.count: %", unique_codepoints_utf32.count);
+  
+  for_each(u, unique_codepoints_utf32) {
+    Text("[%d] Code point as hex: 0x%X", u, unique_codepoints_utf32[u]);
+  }
+  
+  Text("files_sorted_by_size size in bytes: %lld", ex1w.files_sorted_by_size.count * sizeof(string));
+  Text("files_sorted_by_modtime size in bytes: %lld", ex1w.files_sorted_by_modtime.count * sizeof(string));
+  
+  for (s64 i = 1; i < 128; i += 1) {
+    u8 cstring[2] = {};
+    cstring[0] = (u8)i;
+    cstring[1] = 0;
+    Text("codepoint[0x%X]: %s, count: %lld", i, cstring, count_ascii_codepoints[i]);
   }
 }
 
@@ -215,10 +224,12 @@ void Ex1_Control_Panel () { using namespace ImGui;
   // bool all_drives_enumerated = !ex1_ntfs.threads_in_flight.count
   //   && (drives_enumerated == drives.count);
   
-  string file_path = format_string_temp("%s_DriveData.bin", os_get_machine_name().data);
-  // if (!all_drives_enumerated && file_exists(file_path)) {
-  //   Deserialize_ST_File_Enumeration(file_path);
-  // }
+  // string file_path = format_string_temp("%s_DriveData.bin", os_get_machine_name().data);
+  string file_path = "D:/Projects/Cpp/Musa-Cpp-Lib-V2/bin/MUSA-PC3_DriveData.bin";// FIXED path.
+  Text("fixed file_path: %s", file_path.data);
+  if (!all_drives_enumerated && file_exists(file_path)) { // #autoload
+    Deserialize_ST_File_Enumeration(file_path);
+  }
   if (drives.count > 0 && !all_drives_enumerated && file_exists(file_path) && Button("Load from file (this machine)")) {
     Deserialize_ST_File_Enumeration(file_path);
   //   Deserialize_Win32_Drives(file_path);
@@ -234,8 +245,6 @@ void Ex1_Control_Panel () { using namespace ImGui;
   //   }
   // }
   
-  
-  
   // #FileEnumerationST
   if (stfe && stfe->thread_started) {
     // print dirs enumerated, etc
@@ -259,11 +268,8 @@ void Ex1_Control_Panel () { using namespace ImGui;
   if (stfe && stfe->thread_started && !stfe->thread_completed) {
     Assert(stfe->master_thread != nullptr);
     if (thread_is_done(stfe->master_thread)) {
-      push_allocator(GPAllocator());
       thread_deinit(stfe->master_thread, true);
       stfe->thread_completed = true;
-      // Delete(GPAllocator(), stfe);
-      // stfe = nullptr;
     }
   }
   
@@ -274,129 +280,29 @@ void Ex1_Control_Panel () { using namespace ImGui;
     }
   }
   
+  if (all_drives_enumerated && Button("Reset State")) {
+    free_ex1_workspace_and_reset();
+    free_stfe_and_reset();
+    return;
+  }
+  
   if (all_drives_enumerated) {
     Ex1_show_enumeration_workspace();
   }
   
   if (drives.count > 0 && !all_drives_enumerated && Button("Enumerate all NTFS drives")) { //  && ex1_ntfs.initialized
     os_run_file_enumeration_single_threaded();
-    // run_multithreaded_enumeration_thread();
+    // os_run_file_enumeration_multithreaded(); // #disabled for now
     return;
-    /*// #NTFS_MFT_RAW
-    push_allocator(GPAllocator());
-    Array<ArrayView<OS_Drive*>> drive_split;
-    drive_split.allocator = temp(); // this is only needed for this frame
-
-    if (drives.count > os_cpu_physical_core_count()) {
-      s32 thread_count = os_cpu_physical_core_count();
-      array_resize(drive_split, thread_count);
-      ntfs_create_enumeration_threads(thread_count);
-      
-      s32 threads_to_create = thread_count;
-      s64 drives_per_thread = (drives.count / thread_count);
-      s64 remainder = drives.count % thread_count;
-      s64 current_drive = 0;
-      
-      for_each(d, drive_split) {
-        if (d == drive_split.count) {
-          drive_split[d] = ArrayView<OS_Drive*>(remainder);
-        } else {
-          drive_split[d] = ArrayView<OS_Drive*>(drives_per_thread);
-        }
-        
-        for (s64 i = 0; i < drive_split[d].count; i += 1) {
-          drive_split[d][i] = drives[current_drive];
-          current_drive += 1;
-        }
-      }
-      
-      debug_break(); // #TODO: Check that the work has been distributed correctly.
-    } else { // more threads than drives, or same amount
-      s32 thread_count = (s32)drives.count;
-      array_resize(drive_split, drives.count);
-      ntfs_create_enumeration_threads(thread_count);
-      
-      for_each(d, drives) {
-        auto drive = drives[d];
-        drive_split[d] = ArrayView<OS_Drive*>(1); // Arrays of size one are sad :pensive:
-        
-        drive_split[d][0] = drive;
-      }
-    }
-    
-    s64 active_thread_count = drive_split.count;
-    
-    ex1_ntfs.threads_started = true;
-    for (s64 t = 0; t < active_thread_count; t += 1) {
-      Thread* thread = &ex1_ntfs.threads[t];
-      Arena* thread_arena = next_arena(Arena_Reserve::Size_64K);
-      push_arena(thread_arena);
-      auto thread_data = New<NTFS_Enumeration_Task>();
-        thread_data->pool = thread_arena;
-        thread_data->drives = drive_split[t];
-      thread_start(thread, thread_data);
-      array_add(ex1_ntfs.threads_in_flight, thread);
-    }*/
   }
-  
-  /* #NTFS_MFT_RAW
-  if (ex1_ntfs.threads_in_flight.count) {
-    Text("Threads in flight: %d", ex1_ntfs.threads_in_flight.count);
-
-    for_each(t, ex1_ntfs.threads_in_flight) {
-      if (thread_is_done(ex1_ntfs.threads_in_flight[t])) {
-        push_allocator(GPAllocator());
-        
-        Thread* thread = ex1_ntfs.threads_in_flight[t];
-        auto task = thread_task(NTFS_Enumeration_Task);
-        array_free(task->drives);
-
-        // make sure to retreive any data you need to from here!
-        release_arena(task->pool);
-        
-        thread_deinit(ex1_ntfs.threads_in_flight[t], false);
-        array_unordered_remove_by_index(ex1_ntfs.threads_in_flight, t);
-        t -= 1; // check this element index again!
-      }
-    }
-  }*/
-  
-  /* #NTFS_MFT_RAW
-  if (ex1_ntfs.threads_started && !ex1_ntfs.threads_in_flight.count) {
-    // All threads are complete, we're free to clean up remaining memory
-    push_allocator(GPAllocator());
-    array_free(ex1_ntfs.threads);
-    array_free(ex1_ntfs.threads_in_flight);
-    
-    // Instead maybe we should just memset this to zero.
-    reset_struct(&ex1_ntfs);
-  }
-  
-  // How do I tell when all files are enumerated?
-  // check drives[i]->data.paths.wstrings.count count?
-  if (all_drives_enumerated && Button("Save drive data")) {
-    string file_path = format_string_temp("%s_DriveData.bin", os_get_machine_name().data);
-    bool success = Serialize_Win32_Drives(drives, file_path);
-    if (!success) { log_error("Failed to save Win32_Drive data"); }
-  }
-  
-  if (all_drives_enumerated && Button("Clear all drive data")) {
-    os_clear_drive_data();
-  }*/
 }
 
 void ImGui_Debug_Panel () { using namespace ImGui;
   push_allocator(temp());
   
   Begin("Debug Panel");
-  /*SeparatorText("ex1_ntfs");
-  Text("Threads in flight count: %d", ex1_ntfs.threads_in_flight.count);
-  for_each(i, ex1_ntfs.threads) {
-    Text(" [%d] initialized: %d, has_context: %d, has_data: %d", 
-      i, ex1_ntfs.threads[i].proc != nullptr, ex1_ntfs.threads[i].context != nullptr, ex1_ntfs.threads[i].data != nullptr);
-  }*/
   // #cpuid
-  // Text("[cpus] physical: %d, logical: %d, primary: %d, secondary: %d", os_cpu_physical_core_count(), os_cpu_logical_core_count(), os_cpu_primary_core_count(), os_cpu_secondary_core_count());
+  Text("[cpus] physical: %d, logical: %d, primary: %d, secondary: %d", os_cpu_physical_core_count(), os_cpu_logical_core_count(), os_cpu_primary_core_count(), os_cpu_secondary_core_count());
   { SeparatorText("Arena In-Use List");
     lock_guard(&arena_free_list->mutex);
     for (u8 i = 0; i < Arena_Reserve_Count; i += 1) {
diff --git a/src/String_Analysis.cpp b/src/String_Analysis.cpp
new file mode 100644
index 0000000..f61b923
--- /dev/null
+++ b/src/String_Analysis.cpp
@@ -0,0 +1,50 @@
+// 1. Count unique occurrences:
+
+s64 count_ascii_codepoints[128] = {};
+// s64 extended_codepoints[65536] = {};
+
+Array<u32> unique_codepoints_utf32;
+
+force_inline void unique_codepoints_utf32_add_unique (u32 unique) {
+  array_add_if_unique(unique_codepoints_utf32, unique);
+}
+
+void count_unique_chars_from_string (string s) {
+  string s_copy = s;
+  
+  while (s_copy.count > 0) {
+    if (s_copy.data[0] == 0x5C) { // `\` character
+      s_copy.data  += 1;
+      s_copy.count -= 1;
+    }
+    u32 utf32_codepoint; s64 codepoint_source_length;
+    bool success = character_utf8_to_utf32(s_copy.data, s_copy.count, &utf32_codepoint, &codepoint_source_length);
+    
+    if (success) {
+      if (codepoint_source_length == 1) {
+        Assert(utf32_codepoint <= 127);
+          // Add to table
+        count_ascii_codepoints[utf32_codepoint] += 1;
+      } else {
+        unique_codepoints_utf32_add_unique(utf32_codepoint);
+        push_allocator(temp());
+        string codepoint = copy_string(string_view(s_copy, 0, codepoint_source_length));
+        log_todo("#TODO: keep track of unique codepoints. Codepoint: %s", codepoint);
+      }
+    }
+    
+    s_copy.data  += codepoint_source_length;
+    s_copy.count -= codepoint_source_length;
+  }
+}
+
+void count_unique_utf8_chars () { Timed_Block_Print("count_unique_utf8_chars");
+  unique_codepoints_utf32.allocator = GPAllocator();
+
+  Assert(stfe != nullptr);
+  for (s64 i = 0; i < stfe->dirs.offsets->count; i += 1) {
+    string sample = get_file_string_view(stfe, i);
+
+    count_unique_chars_from_string(sample);
+  }
+}
diff --git a/src/explorer_main.cpp b/src/explorer_main.cpp
index a844810..5e0d0fa 100644
--- a/src/explorer_main.cpp
+++ b/src/explorer_main.cpp
@@ -44,7 +44,7 @@ void Explorer_ImGui_Application_Win32 () {
 
   // Setup Dear ImGui context
   IMGUI_CHECKVERSION();
-  printf("ImGui Version %s \n", ImGui::GetVersion());
+  log("ImGui Version %s \n", ImGui::GetVersion());
   
   imgui_context = ImGui::CreateContext();