diff --git a/4ed.cpp b/4ed.cpp
index 9a8015f0..89b4e5a3 100644
--- a/4ed.cpp
+++ b/4ed.cpp
@@ -678,7 +678,7 @@ COMMAND_DECL(interactive_new){
 }
 
 internal File_View*
-app_open_file(App_Vars *vars, General_Memory *general, Panel *panel,
+app_open_file(App_Vars *vars, Mem_Options *mem, Panel *panel,
               Working_Set *working_set, String *string, Style *style,
               Live_Views *live_set, Command_Data *command_data){
     File_View *result = 0;
@@ -690,7 +690,7 @@ app_open_file(App_Vars *vars, General_Memory *general, Panel *panel,
         Get_File_Result file = working_set_get_available_file(working_set);
         if (file.file){
             file_get_dummy(file.file);
-            created_file = file_create(general, file.file, (u8*)string->str, style->font);
+            created_file = file_create(mem, file.file, (u8*)string->str, style->font);
             table_add(&working_set->table, file.file->source_path, file.index);
             if (created_file){
                 target_file = file.file;
@@ -725,7 +725,7 @@ app_open_file(App_Vars *vars, General_Memory *general, Panel *panel,
 
 #if BUFFER_EXPERIMENT_SCALPEL <= 0
         if (created_file && target_file->tokens_exist)
-            file_first_lex_parallel(general, target_file);
+            file_first_lex_parallel(&mem->general, target_file);
 #endif
     }
     
@@ -762,7 +762,7 @@ COMMAND_DECL(interactive_open){
     
     if (filename){
         String string = make_string(filename, filename_len);
-        if (app_open_file(vars, &mem->general, panel, working_set,
+        if (app_open_file(vars, mem, panel, working_set,
                           &string, style, live_set, command)) made_file = 1;
     }
     
@@ -794,7 +794,7 @@ COMMAND_DECL(reopen){
     USE_VARS(vars);
     
     Editing_File temp_file;
-    if (file_create(&mem->general, &temp_file, (u8*)make_c_str(file->source_path), style->font)){
+    if (file_create(mem, &temp_file, (u8*)make_c_str(file->source_path), style->font)){
         file_close(&mem->general, file);
         *file = temp_file;
         file->source_path.str = file->source_path_;
@@ -1566,7 +1566,7 @@ COMMAND_DECL(build){
         }
         
         if (file){
-            file_create_super_locked(&mem->general, file, (u8*)buffer_name, style->font);
+            file_create_super_locked(mem, file, (u8*)buffer_name, style->font);
             table_add(&working_set->table, file->live_name, index);
             
             View *new_view = live_set_alloc_view(live_set, mem);
@@ -3042,7 +3042,7 @@ app_step(Thread_Context *thread, Key_Codes *codes,
             case DACT_OPEN:
             {
                 command_data.view = (View*)
-                    app_open_file(vars, general,panel, working_set, string, style, live_set, &command_data);
+                    app_open_file(vars, mem, panel, working_set, string, style, live_set, &command_data);
             }break;
             
             case DACT_SAVE_AS:
@@ -3070,7 +3070,7 @@ app_step(Thread_Context *thread, Key_Codes *codes,
             case DACT_NEW:
             {
                 Get_File_Result file = working_set_get_available_file(working_set);
-                file_create_empty(general, file.file, (u8*)string->str, style->font);
+                file_create_empty(mem, file.file, (u8*)string->str, style->font);
                 table_add(&working_set->table, file.file->source_path, file.index);
                 
                 View *new_view = live_set_alloc_view(live_set, mem);
diff --git a/4ed_file_view.cpp b/4ed_file_view.cpp
index 2eca2df5..f8039c96 100644
--- a/4ed_file_view.cpp
+++ b/4ed_file_view.cpp
@@ -17,9 +17,12 @@
 #elif BUFFER_EXPERIMENT_SCALPEL == 1
 #include "buffer/4coder_gap_buffer.cpp"
 #define Buffer_Type Gap_Buffer
-#else
+#elif BUFFER_EXPERIMENT_SCALPEL == 2
 #include "buffer/4coder_multi_gap_buffer.cpp"
 #define Buffer_Type Multi_Gap_Buffer
+#else
+#include "buffer/4coder_rope_buffer.cpp"
+#define Buffer_Type Rope_Buffer
 #endif
 
 #include "buffer/4coder_buffer_abstract.cpp"
@@ -1388,9 +1391,10 @@ alloc_for_buffer(void *context, int *size){
 }
 
 internal void
-file_create_from_string(General_Memory *general, Editing_File *file, u8 *filename, Font *font, String val, b32 super_locked = 0){
+file_create_from_string(Mem_Options *mem, Editing_File *file, u8 *filename, Font *font, String val, b32 super_locked = 0){
     *file = {};
-#if BUFFER_EXPERIMENT_SCALPEL <= 2
+    General_Memory *general = &mem->general;
+#if BUFFER_EXPERIMENT_SCALPEL <= 3
     Buffer_Init_Type init = buffer_begin_init(&file->buffer, val.str, val.size);
     for (; buffer_init_need_more(&init); ){
         i32 page_size = buffer_init_page_size(&init);
@@ -1399,7 +1403,11 @@ file_create_from_string(General_Memory *general, Editing_File *file, u8 *filenam
         void *data = general_memory_allocate(general, page_size, BUBBLE_BUFFER);
         buffer_init_provide_page(&init, data, page_size);
     }
-    i32 init_success = buffer_end_init(&init);
+
+    Partition *part = &mem->part;
+    i32 scratch_size = partition_remaining(part);
+    Assert(scratch_size > 0);
+    i32 init_success = buffer_end_init(&init, part->base + part->pos, scratch_size);
     Assert(init_success);
 #endif
     
@@ -1444,14 +1452,14 @@ file_create_from_string(General_Memory *general, Editing_File *file, u8 *filenam
 }
 
 internal bool32
-file_create(General_Memory *general, Editing_File *file, u8 *filename, Font *font){
+file_create(Mem_Options *mem, Editing_File *file, u8 *filename, Font *font){
     bool32 result = 0;
     
     File_Data raw_file = system_load_file(filename);
     if (raw_file.data){
         result = 1;
         String val = make_string((char*)raw_file.data, raw_file.size);
-        file_create_from_string(general, file, filename, font, val);
+        file_create_from_string(mem, file, filename, font, val);
         system_free_file(raw_file);
     }
     
@@ -1459,18 +1467,18 @@ file_create(General_Memory *general, Editing_File *file, u8 *filename, Font *fon
 }
 
 internal b32
-file_create_empty(General_Memory *general, Editing_File *file, u8 *filename, Font *font){
+file_create_empty(Mem_Options *mem, Editing_File *file, u8 *filename, Font *font){
     b32 result = 1;
     String empty_str = {};
-    file_create_from_string(general, file, filename, font, empty_str);
+    file_create_from_string(mem, file, filename, font, empty_str);
     return result;
 }
 
 internal b32
-file_create_super_locked(General_Memory *general, Editing_File *file, u8 *filename, Font *font){
+file_create_super_locked(Mem_Options *mem, Editing_File *file, u8 *filename, Font *font){
     b32 result = 1;
     String empty_str = {};
-    file_create_from_string(general, file, filename, font, empty_str, 1);
+    file_create_from_string(mem, file, filename, font, empty_str, 1);
     return result;
 }
 
@@ -1800,7 +1808,7 @@ struct Edit_Spec{
     Edit_Step step;
 };
 
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
 internal Edit_Step*
 file_post_undo(General_Memory *general, Editing_File *file,
                Edit_Step step, bool32 do_merge, bool32 can_merge){
@@ -1876,7 +1884,7 @@ undo_stack_pop(Edit_Stack *stack){
     }
 }
 
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
 internal void
 file_post_redo(General_Memory *general, Editing_File *file, Edit_Step step){
     Edit_Stack *redo = &file->undo.redo;
@@ -1937,7 +1945,7 @@ file_unpost_history_block(Editing_File *file){
     file->undo.history_head_block = old_head->prev_block;
 }
 
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
 internal Edit_Step*
 file_post_history(General_Memory *general, Editing_File *file,
                   Edit_Step step, bool32 do_merge, bool32 can_merge){
@@ -2284,7 +2292,7 @@ internal void
 file_update_history_before_edit(Mem_Options *mem, Editing_File *file, Edit_Step step, u8 *str,
                                 History_Mode history_mode){
     if (!file->undo.undo.edits) return;
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
     General_Memory *general = &mem->general;
     
 #if FRED_SLOW
@@ -2531,7 +2539,7 @@ file_do_single_edit(Mem_Options *mem, Editing_File *file,
         file_relex_parallel(mem, file, start, end, shift_amount);
 #endif
 
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
     Temp_Memory cursor_temp = begin_temp_memory(&mem->part);
     i32 cursor_max = layout->panel_max_count * 2;
     Cursor_With_Index *cursors = push_array(&mem->part, Cursor_With_Index, cursor_max);
@@ -2573,7 +2581,7 @@ internal void
 view_do_white_batch_edit(Mem_Options *mem, File_View *view, Editing_File *file,
                          Editing_Layout *layout, Edit_Spec spec, History_Mode history_mode){
     if (view->locked) return;
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
     Assert(file);
     ProfileMomentFunction();
     
@@ -2952,7 +2960,7 @@ file_compute_whitespace_edit(Mem_Options *mem, Editing_File *file, i32 cursor_po
                              Buffer_Edit *edits, char *str_base, i32 str_size,
                              Buffer_Edit *inverse_array, char *inv_str, i32 inv_max,
                              i32 edit_count){
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
     General_Memory *general = &mem->general;
     
     i32 inv_str_pos = 0;
@@ -2986,7 +2994,7 @@ file_compute_whitespace_edit(Mem_Options *mem, Editing_File *file, i32 cursor_po
 
 internal void
 view_clean_whitespace(Mem_Options *mem, File_View *view, Editing_Layout *layout){
-#if BUFFER_EXPERIMENT_SCALPEL <= 1
+#if BUFFER_EXPERIMENT_SCALPEL <= 2
     Editing_File *file = view->file;
     Assert(file && !file->is_dummy);
     Partition *part = &mem->part;
diff --git a/4ed_math.cpp b/4ed_math.cpp
index 59c5af0e..a1eddb7a 100644
--- a/4ed_math.cpp
+++ b/4ed_math.cpp
@@ -83,6 +83,18 @@ DIVCEIL32(i32 n, i32 d) {
 inline real32
 FRACPART32(real32 x) { return x - (i32)x; }
 
+inline u32
+ROUNDPOT32(u32 v){
+    v--;
+    v |= v >> 1;
+    v |= v >> 2;
+    v |= v >> 4;
+    v |= v >> 8;
+    v |= v >> 16;
+    v++;
+    return v;
+}
+
 /*
  * Rectangles
  */
diff --git a/buffer/4coder_gap_buffer.cpp b/buffer/4coder_gap_buffer.cpp
index 654399c5..2c2da69f 100644
--- a/buffer/4coder_gap_buffer.cpp
+++ b/buffer/4coder_gap_buffer.cpp
@@ -78,7 +78,7 @@ buffer_init_provide_page(Gap_Buffer_Init *init, void *page, int page_size){
 }
 
 internal_4tech int
-buffer_end_init(Gap_Buffer_Init *init){
+buffer_end_init(Gap_Buffer_Init *init, void *scratch, int scratch_size){
     Gap_Buffer *buffer;
     int osize1, size1, size2, size;
     int result;
@@ -292,7 +292,8 @@ buffer_replace_range(Gap_Buffer *buffer, int start, int end, char *str, int len,
 
 // NOTE(allen): This could should be optimized for Gap_Buffer
 internal_4tech int
-buffer_batch_edit_step(Buffer_Batch_State *state, Gap_Buffer *buffer, Buffer_Edit *sorted_edits, char *strings, int edit_count, int *request_amount){
+buffer_batch_edit_step(Buffer_Batch_State *state, Gap_Buffer *buffer, Buffer_Edit *sorted_edits,
+                       char *strings, int edit_count, int *request_amount){
     Buffer_Edit *edit;
     int i, result;
     int shift_total, shift_amount;
diff --git a/buffer/4coder_golden_array.cpp b/buffer/4coder_golden_array.cpp
index 2e7592eb..645a4a5b 100644
--- a/buffer/4coder_golden_array.cpp
+++ b/buffer/4coder_golden_array.cpp
@@ -76,7 +76,7 @@ buffer_init_provide_page(Buffer_Init *init, void *page, int page_size){
 }
 
 internal_4tech int
-buffer_end_init(Buffer_Init *init){
+buffer_end_init(Buffer_Init *init, void *scratch, int scratch_size){
     Buffer *buffer;
     int result;
 
diff --git a/buffer/4coder_multi_gap_buffer.cpp b/buffer/4coder_multi_gap_buffer.cpp
index 25ad00d1..225f2c61 100644
--- a/buffer/4coder_multi_gap_buffer.cpp
+++ b/buffer/4coder_multi_gap_buffer.cpp
@@ -79,7 +79,7 @@ buffer_begin_init(Multi_Gap_Buffer *buffer, char *data, int size){
     return(init);
 }
 
-internal_4tech int
+inline_4tech int
 buffer_init_need_more(Multi_Gap_Buffer_Init *init){
     int result;
     result = 1;
@@ -88,7 +88,7 @@ buffer_init_need_more(Multi_Gap_Buffer_Init *init){
     return(result);
 }
 
-internal_4tech int
+inline_4tech int
 buffer_init_page_size(Multi_Gap_Buffer_Init *init){
     Multi_Gap_Buffer *buffer;
     int result;
@@ -115,7 +115,7 @@ buffer_init_provide_page(Multi_Gap_Buffer_Init *init, void *page, int page_size)
 }
 
 internal_4tech int
-buffer_end_init(Multi_Gap_Buffer_Init *init){
+buffer_end_init(Multi_Gap_Buffer_Init *init, void *scratch, int scratch_size){
     Multi_Gap_Buffer *buffer;
     Fixed_Width_Gap_Buffer *gap;
     int result;
@@ -419,16 +419,16 @@ buffer_replace_range(Multi_Gap_Buffer *buffer, int start, int end, char *str, in
     gap = gaps + gap_start;
     if (buffer->edit_stage == 1){
         if (gap_start < gap_end && gap_start+1 < buffer->chunk_count){
-            supplanted_gaps = gap_end - gap_start + 1;
+            supplanted_gaps = gap_end - gap_start - 1;
             if (buffer->chunk_max - buffer->chunk_alloced >= supplanted_gaps){
                 ++gap;
                 memcpy_4tech(gaps + buffer->chunk_alloced, gap, sizeof(*gaps)*supplanted_gaps);
                 memmove_4tech(gap, gaps + gap_end, sizeof(*gaps)*(buffer->chunk_alloced - gap_start - 1));
-                buffer->chunk_count -= (gap_end - gap_start + 1);
+                buffer->chunk_count -= (gap_end - gap_start - 1);
         
                 local_end = end - gap->start_pos;
         
-                if (gap->size1 >= local_end){
+                if (local_end >= gap->size1){
                     gap->size2 -= (local_end - gap->size1);
                     gap->size1 = 0;
                 }
@@ -436,6 +436,7 @@ buffer_replace_range(Multi_Gap_Buffer *buffer, int start, int end, char *str, in
                     memmove_4tech(gap->data, gap->data + local_end, gap->size1 - local_end);
                     gap->size1 -= local_end;
                 }
+                gap->gap_size = fixed_width_buffer_size - gap->size2 - gap->size1;
         
                 --gap;
             }
@@ -449,10 +450,11 @@ buffer_replace_range(Multi_Gap_Buffer *buffer, int start, int end, char *str, in
         buffer->edit_stage = 2;
     }
     
-    shift_amount = (len - (end - start));
     start -= gap->start_pos;
     end -= gap->start_pos;
+    assert_4tech(start >= 0 && end >= 0);
     if (end > gap->size1 + gap->size2) end = gap->size1 + gap->size2;
+    shift_amount = (len - (end - start));
     
     if (shift_amount + gap->size1 + gap->size2 <= fixed_width_buffer_size){
         data = gap->data;
@@ -514,44 +516,37 @@ buffer_replace_range(Multi_Gap_Buffer *buffer, int start, int end, char *str, in
                     gap->size1 = start;
                 }
                 
-                if (gap->size1 > fixed_width_buffer_half_size){
-                    move_size = gap->size1 - fixed_width_buffer_half_size;
-                    memmove_4tech(data + gap->size1 + gap->gap_size - move_size, data + end, move_size);
-                    gap->size1 -= move_size + (end - start);
-                    gap->size2 += move_size;
-                }
-                else if (gap->size2 > fixed_width_buffer_half_size){
-                    move_size = gap->size2 - fixed_width_buffer_half_size;
-                    memmove_4tech(data + gap->size1, data + gap->size1 + gap->gap_size, move_size);
-                    gap->size1 += move_size;
-                    gap->size2 -= move_size + (end - start);
-                }                
-                
                 dgap = gap + required_empty_buffers;
                 dpos = gap->size1 + gap->gap_size;
                 memcpy_4tech(dgap->data + dpos, data + dpos, gap->size2);
                 dgap->size2 = gap->size2;
                 gap->size2 = 0;
                 
-                middle_size = div_ceil_4tech(len, (required_empty_buffers * 2));
-                
-                head_size = middle_size;
-                tail_size = middle_size;
-                
-                if (head_size + gap->size1 + 256 > fixed_width_buffer_size){
-                    head_size = fixed_width_buffer_size - gap->size1 - 256;
-                    if (head_size < 0) head_size = 0;
-                }
-                
-                if (tail_size + dgap->size2 + 256 > fixed_width_buffer_size){
-                    tail_size = fixed_width_buffer_size - dgap->size2 - 256;
-                    if (tail_size < 0) tail_size = 0;
-                }
+                tail_size = fixed_width_buffer_half_size - dgap->size2;
+                if (tail_size < 0) tail_size = 0;
 
-                if (required_empty_buffers-1 > 0)
-                    middle_size = div_ceil_4tech(len - head_size - tail_size, (required_empty_buffers-1)*2);
-                else
+                if (tail_size < len){
+                    middle_size = div_ceil_4tech(len - tail_size, (required_empty_buffers * 2));
+                
+                    head_size = middle_size;
+                
+                    if (head_size + gap->size1 + 256 > fixed_width_buffer_size){
+                        head_size = fixed_width_buffer_size - gap->size1 - 256;
+                        if (head_size < 0) head_size = 0;
+                    }
+
+                    if (required_empty_buffers-1 > 0){
+                        middle_size = div_ceil_4tech(len - head_size - tail_size, (required_empty_buffers-1)*2);
+                    }
+                    else{
+                        middle_size = 0;
+                        assert_4tech(head_size + tail_size >= len);
+                    }
+                }
+                else{
                     middle_size = 0;
+                    head_size = 0;
+                }
 
                 mem_pos = 0;
                 if (head_size > len - mem_pos) head_size = len - mem_pos;
@@ -578,7 +573,6 @@ buffer_replace_range(Multi_Gap_Buffer *buffer, int start, int end, char *str, in
                     
                     gap->gap_size = fixed_width_buffer_size - (gap->size1 + gap->size2);
                     local_start_pos += gap->size1 + gap->size2;
-                    ++gap;
                 }
                 
                 if (tail_size > len - mem_pos) tail_size = len - mem_pos;
@@ -588,6 +582,8 @@ buffer_replace_range(Multi_Gap_Buffer *buffer, int start, int end, char *str, in
                 memcpy_4tech(gap->data, str + mem_pos, tail_size);
                 mem_pos += tail_size;
                 assert_4tech(mem_pos == len);
+                debug_4tech(local_start_pos += gap->size1 + gap->size2);
+                assert_4tech(local_start_pos == buffer->size);
 
                 buffer->chunk_count += required_empty_buffers;
 
@@ -618,34 +614,6 @@ mugab_replace_range_end:
     return(result);
 }
 
-internal_4tech void*
-buffer_edit_provide_memory(Multi_Gap_Buffer *buffer, void *new_data, int size){
-    void *result;
-    Fixed_Width_Gap_Buffer *gap;
-
-    if (buffer->grow_gaps){
-        assert_4tech(size >= buffer->chunk_max*sizeof(*buffer->gaps));
-        
-        result = buffer->gaps;
-        memcpy_4tech(new_data, buffer->gaps, buffer->chunk_alloced*sizeof(*buffer->gaps));
-        buffer->gaps = (Fixed_Width_Gap_Buffer*)new_data;
-        buffer->chunk_max = size / sizeof(*buffer->gaps);
-        buffer->grow_gaps = 0;
-    }
-    
-    else{
-        assert_4tech(buffer->chunk_max > buffer->chunk_alloced);
-        assert_4tech(size >= fixed_width_buffer_size);
-        
-        gap = &buffer->gaps[buffer->chunk_alloced++];
-        *gap = {};
-        gap->data = (char*)new_data;
-        result = 0;
-    }
-    
-    return(result);
-}
-
 internal_4tech int
 buffer_mugab_check(Multi_Gap_Buffer *buffer){
     Fixed_Width_Gap_Buffer *gap;
@@ -674,6 +642,61 @@ buffer_mugab_check(Multi_Gap_Buffer *buffer){
     return(result);
 }
 
+// NOTE(allen): This could should be optimized for Multi_Gap_Buffer
+internal_4tech int
+buffer_batch_edit_step(Buffer_Batch_State *state, Multi_Gap_Buffer *buffer, Buffer_Edit *sorted_edits,
+                       char *strings, int edit_count, int *request_amount){
+    Buffer_Edit *edit;
+    int i, result;
+    int shift_total, shift_amount;
+    
+    result = 0;
+    shift_total = state->shift_total;
+    i = state->i;
+    
+    edit = sorted_edits + i;
+    for (; i < edit_count; ++i, ++edit){
+        result = buffer_replace_range(buffer, edit->start + shift_total, edit->end + shift_total,
+                                      strings + edit->str_start, edit->len, &shift_amount, request_amount);
+        if (result) break;
+        buffer_mugab_check(buffer);
+        shift_total += shift_amount;
+    }
+    
+    state->shift_total = shift_total;
+    state->i = i;
+    
+    return(result);
+}
+
+internal_4tech void*
+buffer_edit_provide_memory(Multi_Gap_Buffer *buffer, void *new_data, int size){
+    void *result;
+    Fixed_Width_Gap_Buffer *gap;
+
+    if (buffer->grow_gaps){
+        assert_4tech(size >= buffer->chunk_max*sizeof(*buffer->gaps));
+        
+        result = buffer->gaps;
+        memcpy_4tech(new_data, buffer->gaps, buffer->chunk_alloced*sizeof(*buffer->gaps));
+        buffer->gaps = (Fixed_Width_Gap_Buffer*)new_data;
+        buffer->chunk_max = size / sizeof(*buffer->gaps);
+        buffer->grow_gaps = 0;
+    }
+    
+    else{
+        assert_4tech(buffer->chunk_max > buffer->chunk_alloced);
+        assert_4tech(size >= fixed_width_buffer_size);
+        
+        gap = &buffer->gaps[buffer->chunk_alloced++];
+        *gap = {};
+        gap->data = (char*)new_data;
+        result = 0;
+    }
+    
+    return(result);
+}
+
 // BOTTOM
 
 
diff --git a/buffer/4coder_rope_buffer.cpp b/buffer/4coder_rope_buffer.cpp
new file mode 100644
index 00000000..2729c8a3
--- /dev/null
+++ b/buffer/4coder_rope_buffer.cpp
@@ -0,0 +1,300 @@
+/* 
+ * Mr. 4th Dimention - Allen Webster
+ *  Four Tech
+ *
+ * public domain -- no warranty is offered or implied; use this code at your own risk
+ * 
+ * 03.11.2015
+ * 
+ * Buffer data object
+ *  type - Rope
+ * 
+ */
+
+// TOP
+
+typedef struct Rope_Node{
+    int left, right, parent;
+    int left_total, total;
+    int str_start;
+} Rope_Node;
+
+typedef struct Rope_String{
+    int next_free;
+} Rope_String;
+
+#define rope_string_full_size 256
+#define rope_string_width (rope_string_full_size-sizeof(Rope_String))
+
+typedef struct Rope_Buffer{
+    void *data;
+    int free_rope_string;
+    int string_count;
+    
+    Rope_Node *nodes;
+    int free_rope_node;
+    int node_count;
+    
+    float *line_widths;
+    int *line_starts;
+    int line_count;
+    int widths_count;
+    int line_max;
+    int widths_max;
+} Rope_Buffer;
+
+inline_4tech int
+buffer_good(Rope_Buffer *buffer){
+    int good;
+    good = (buffer->data != 0);
+    return(good);
+}
+
+inline_4tech int
+buffer_size(Rope_Buffer *buffer){
+    int size;
+    size = buffer->nodes->left_total;
+    return(size);
+}
+
+typedef struct{
+    Rope_Buffer *buffer;
+    char *data;
+    int size;
+
+    int rope_string_count;
+    int node_count;
+} Rope_Buffer_Init;
+
+internal_4tech Rope_Buffer_Init
+buffer_begin_init(Rope_Buffer *buffer, char *data, int size){
+    Rope_Buffer_Init init;
+    
+    init.buffer = buffer;
+    init.data = data;
+    init.size = size;
+    
+    init.node_count = div_ceil_4tech(size, rope_string_width);
+
+    if (init.node_count < 4){
+        init.node_count = 7;
+        init.rope_string_count = 4;
+    }
+    else{
+        init.rope_string_count = round_pot_4tech(init.node_count);
+        init.node_count = init.rope_string_count*2 - 1;
+    }
+    
+    return(init);
+}
+
+internal_4tech int
+buffer_init_need_more(Rope_Buffer_Init *init){
+    Rope_Buffer *buffer;
+    int result;
+    buffer = init->buffer;
+    result = 1;
+    if (buffer->data != 0 && buffer->nodes != 0)
+        result = 0;
+    return(result);
+}
+
+inline_4tech int
+buffer_init_page_size(Rope_Buffer_Init *init){
+    Rope_Buffer *buffer;
+    int result;
+    buffer = init->buffer;
+    if (buffer->data) result = init->node_count*sizeof(Rope_Node);
+    else result = init->rope_string_count*rope_string_full_size;
+    return(result);
+}
+
+internal_4tech void
+buffer_init_provide_page(Rope_Buffer_Init *init, void *page, int page_size){
+    Rope_Buffer *buffer;
+    buffer = init->buffer;
+    
+    if (buffer->data){
+        assert_4tech(buffer->nodes == 0);
+        assert_4tech(page_size >= init->node_count*sizeof(Rope_Node));
+        buffer->nodes = (Rope_Node*)page;
+        init->node_count = page_size / sizeof(Rope_Node);
+    }
+    else{
+        assert_4tech(page_size >= init->rope_string_count*rope_string_full_size);
+        buffer->data = page;
+        init->rope_string_count = page_size / rope_string_full_size;
+    }
+}
+
+internal_4tech int
+buffer_alloc_rope_string(Rope_Buffer *buffer, int *result){
+    Rope_String *rope_string;
+    int success;
+    
+    success = 0;
+    if (buffer->free_rope_string >= 0){
+        success = 1;
+        *result = buffer->free_rope_string;
+        rope_string = (Rope_String*)((char*)buffer->data + *result);
+        buffer->free_rope_string = rope_string->next_free;
+        *result += sizeof(Rope_String);
+    }
+    
+    return(success);
+}
+
+internal_4tech void
+buffer_free_rope_string(Rope_Buffer *buffer, int str_start){
+    Rope_String *rope_string;
+
+    str_start -= sizeof(Rope_String);
+    rope_string = (Rope_String*)((char*)buffer->data + str_start);
+    rope_string->next_free = buffer->free_rope_string;
+    buffer->free_rope_string = str_start;
+}
+
+internal_4tech int
+buffer_alloc_rope_node(Rope_Buffer *buffer, int *result){
+    Rope_Node *node;
+    int success;
+    
+    success = 0;
+    if (buffer->free_rope_node > 0){
+        success = 1;
+        *result = buffer->free_rope_node;
+        node = buffer->nodes + *result;
+        buffer->free_rope_node = node->parent;
+    }
+    
+    return(success);
+}
+
+internal_4tech void
+buffer_free_rope_node(Rope_Buffer *buffer, int node_index){
+    Rope_Node *node;
+
+    node = buffer->nodes + node_index;
+    node->parent = buffer->free_rope_node;
+    buffer->free_rope_node = node_index;
+}
+
+typedef struct Rope_Construct_Stage{
+    int parent_index;
+    int is_right_side;
+    int weight;
+} Rope_Construct_Stage;
+
+inline_4tech Rope_Construct_Stage
+buffer_construct_stage(int parent, int right, int weight){
+    Rope_Construct_Stage result;
+    result.parent_index = parent;
+    result.is_right_side = right;
+    result.weight = weight;
+    return(result);
+}
+
+internal_4tech int
+buffer_end_init(Rope_Buffer_Init *init, void *scratch, int scratch_size){
+    Rope_Construct_Stage *stack, *stage;
+    Rope_Buffer *buffer;
+    Rope_String *rope_string;
+    Rope_Node *node;
+    char *src, *dest;
+    int node_index;
+    int i, top, stack_max, is_right_side;
+    int read_pos, read_end;
+    int result;
+    int count;
+    
+    src = init->data;
+    read_pos = 0;
+    read_end = init->size;
+    
+    result = 0;
+    buffer = init->buffer;
+    if (buffer->nodes && buffer->data){
+        // NOTE(allen): initialize free lists
+        buffer->string_count = init->rope_string_count;
+        buffer->free_rope_string = 0;
+        
+        rope_string = (Rope_String*)buffer->data;
+        count = init->rope_string_count;
+        for (i = 0; i < count-1; ++i){
+            rope_string->next_free = rope_string_full_size*(i+1);
+            rope_string = (Rope_String*)((char*)rope_string + rope_string_full_size);
+        }
+        rope_string->next_free = -1;
+
+        buffer->node_count = init->node_count;
+        buffer->free_rope_node = 1;
+        
+        node = buffer->nodes + 1;
+        count = init->node_count;
+        for (i = 1; i < count; ++i, ++node){
+            node->parent = i+1;
+        }
+        node->parent = 0;
+        
+        result = 1;
+        
+        // NOTE(allen): initialize tree
+        node = buffer->nodes;
+        node->parent = 0;
+        node->total = init->size;
+        node->left_total = init->size;
+        
+        stack = (Rope_Construct_Stage*)scratch;
+        stack_max = scratch_size / sizeof(Rope_Construct_Stage);
+        top = 0;
+        
+        stack[top++] = buffer_construct_stage(0, 0, init->size);
+        for (;top > 0;){
+            stage = stack + (--top);
+            
+            if (buffer_alloc_rope_node(buffer, &node_index)){
+                node = buffer->nodes + node_index;
+                node->parent = stage->parent_index;
+                node->total = stage->weight;
+                is_right_side = stage->is_right_side;
+                if (stage->weight > rope_string_width){
+                    node->left_total = stage->weight / 2;
+                    assert_4tech(top < stack_max);
+                    stack[top++] = buffer_construct_stage(node_index, 1, node->total - node->left_total);
+                    assert_4tech(top < stack_max);
+                    stack[top++] = buffer_construct_stage(node_index, 0, node->left_total);
+                }
+                else{
+                    node->left_total = 0;
+                    node->left = 0;
+                    node->right = 0;
+                    if (buffer_alloc_rope_string(buffer, &node->str_start)){
+                        dest = (char*)buffer->data + node->str_start;
+                        assert_4tech(read_pos < read_end);
+                        memcpy_4tech(dest, src + read_pos, node->total);
+                        read_pos += node->total;
+                    }
+                    else{
+                        result = 0;
+                        break;
+                    }
+                }
+                node = buffer->nodes + node->parent;
+                if (is_right_side) node->right = node_index;
+                else node->left = node_index;
+            }
+            else{
+                result = 0;
+                break;
+            }
+        }
+    }
+    
+    assert_4tech(!result || read_pos == read_end);
+    
+    return(result);
+}
+
+// BOTTOM
+
+
diff --git a/buffer/4coder_shared.cpp b/buffer/4coder_shared.cpp
index bb8e0019..8605b17a 100644
--- a/buffer/4coder_shared.cpp
+++ b/buffer/4coder_shared.cpp
@@ -66,6 +66,10 @@ lroundup_(int x, int granularity){
 #define round_up_4tech(x,g) lroundup_(x,g)
 #endif
 
+#ifndef round_pot_4tech
+#define round_pot_4tech ROUNDPOT32
+#endif
+
 inline_4tech float
 measure_character(void *advance_data, int stride, char character){
     char *advances;
diff --git a/win32_4ed.cpp b/win32_4ed.cpp
index 2eb405d6..df08cf5f 100644
--- a/win32_4ed.cpp
+++ b/win32_4ed.cpp
@@ -58,7 +58,7 @@
 #define FPS 30
 #define FRAME_TIME (1000000 / FPS)
 
-#define BUFFER_EXPERIMENT_SCALPEL 1
+#define BUFFER_EXPERIMENT_SCALPEL 3
 
 #include "4ed_meta.h"