diff --git a/DtsodParser/DtsodV24_deserialize.c b/DtsodParser/DtsodV24_deserialize.c
index 6e1de1c..d410e08 100644
--- a/DtsodParser/DtsodV24_deserialize.c
+++ b/DtsodParser/DtsodV24_deserialize.c
@@ -3,8 +3,6 @@
 
 #define ARR_BC 64
 #define ARR_BL 1024
-#define STRB_BC 64
-#define STRB_BL 1024
 
 
 typedef struct DeserializeSharedData{
@@ -105,7 +103,7 @@ Maybe __ReadName(DeserializeSharedData* shared){
                 safethrow_wrongchar(c,;);
             return SUCCESS(UniPtr(CharPtr,NULL));
         case ':':
-            return SUCCESS(UniPtr(CharPtr,string_cpToCptr(nameStr)));
+            return SUCCESS(UniPtr(CharPtr,string_extract(nameStr)));
         case '$':
             if(nameStr.length!=0)
                 safethrow_wrongchar(c,;);
@@ -130,19 +128,18 @@ Maybe __ReadValue(DeserializeSharedData* shared);
 Maybe __ReadString(DeserializeSharedData* shared){
     char c;
     bool prevIsBackslash=false;
-    StringBuilder* b=StringBuilder_create(STRB_BC,STRB_BL);
+    StringBuilder* b=StringBuilder_create();
 
     while ((c=*++text)){
         if(c=='"') {
             if(prevIsBackslash) {
                 // replacing <\"> with <">
-                StringBuilder_pop(b); 
+                StringBuilder_rmchar(b); 
                 StringBuilder_append_char(b,c);
                 prevIsBackslash=false;
             }
             else {
-                char* str=StringBuilder_build(b);
-                StringBuilder_free(b);
+                char* str=StringBuilder_build(b).ptr;
                 return SUCCESS(UniPtr(CharPtr,str));
             }
         } 
@@ -188,7 +185,7 @@ Maybe __ParseValue(DeserializeSharedData* shared, string str){
             break;
         // Float64
         case 'f': {
-            char* _c=string_cpToCptr(str);
+            char* _c=string_extract(str);
             Unitype rez=Uni(Float64,strtod(_c,NULL));
             free(_c);
             return SUCCESS(rez);
@@ -196,7 +193,7 @@ Maybe __ParseValue(DeserializeSharedData* shared, string str){
         // UInt64
         case 'u': {
             uint64 lu=0;
-            char* _c=string_cpToCptr(str);
+            char* _c=string_extract(str);
             if(sscanf(_c,"%lu",&lu)!=1){
                 char err[64];
                 IFWIN(
@@ -212,7 +209,7 @@ Maybe __ParseValue(DeserializeSharedData* shared, string str){
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9': {
             int64 li=0;
-            char* _c=string_cpToCptr(str);
+            char* _c=string_extract(str);
             if(sscanf(_c,"%li",&li)!=1){
                 char err[64];
                 IFWIN(
diff --git a/DtsodParser/DtsodV24_serialize.c b/DtsodParser/DtsodV24_serialize.c
index ab09ffd..d4869f0 100644
--- a/DtsodParser/DtsodV24_serialize.c
+++ b/DtsodParser/DtsodV24_serialize.c
@@ -1,9 +1,6 @@
 #include "DtsodV24.h"
 #include "../String/StringBuilder.h"
 
-// 65536 max length!
-#define STRB_BC 64
-#define STRB_BL 1024
 
 typedef struct SerializeSharedData{
     StringBuilder* sh_builder; 
@@ -35,7 +32,7 @@ Maybe __AppendValue(SerializeSharedData* shared, Unitype u){
             addc('u');
             break;
         case Float64:
-            StringBuilder_append_double(b,u.Float64);
+            StringBuilder_append_float64(b,u.Float64);
             addc('f');
             break;
         case CharPtr:
@@ -64,7 +61,7 @@ Maybe __AppendValue(SerializeSharedData* shared, Unitype u){
                 try(AppendValue(e),__,;);
                 addc(',');
             }));
-            StringBuilder_pop(b);
+            StringBuilder_rmchar(b);
             addc('\n');
             tabs--;
             AppendTabs();
@@ -106,9 +103,8 @@ Maybe __serialize(StringBuilder* _b, uint8 _tabs, Hashtable* dtsod){
 }
 
 Maybe DtsodV24_serialize(Hashtable* dtsod){
-    StringBuilder* sb=StringBuilder_create(STRB_BC,STRB_BL);
-    try(__serialize(sb,0,dtsod),__, StringBuilder_free((sb)));
-    char* str=StringBuilder_build(sb);
-    StringBuilder_free((sb));
+    StringBuilder* sb=StringBuilder_create();
+    try(__serialize(sb,0,dtsod),__, StringBuilder_free(sb));
+    char* str=StringBuilder_build(sb).ptr;
     return SUCCESS(UniPtr(CharPtr, str));
 }
diff --git a/String/StringBuilder.c b/String/StringBuilder.c
index f11ea13..a577361 100644
--- a/String/StringBuilder.c
+++ b/String/StringBuilder.c
@@ -1,42 +1,109 @@
 #include "StringBuilder.h"
 
-StringBuilder* StringBuilder_create(uint16 max_blocks_count, uint16 max_block_length){
-    return Autoarr_create(int8,max_blocks_count,max_block_length);
+define_Autoarr(string)
+
+#define MAXLENGTH 32768
+#define BL_C 32
+#define BL_L 1024
+
+
+void complete_buf(StringBuilder* b){
+    if(!b->compl_bufs) 
+        b->compl_bufs=Autoarr_create(string,BL_C,BL_L);
+    uint32 len=Autoarr_length(b->curr_buf);
+    if(!len) return;
+    string str={.length=len, .ptr=malloc(len)};
+    uint32 i=0;
+    Autoarr_foreach(b->curr_buf, c, ({
+        str.ptr[i++]=c;
+    }));
+    Autoarr_add(b->compl_bufs,str);
+    Autoarr_free(b->curr_buf);
+    b->curr_buf=Autoarr_create(int8,BL_C,BL_L);
+}
+
+void try_complete_buf(StringBuilder* b){
+    if(b->curr_buf->blocks_count==BL_C)
+        complete_buf(b);
+}
+
+
+StringBuilder* StringBuilder_create(){
+    StringBuilder* b=malloc(sizeof(StringBuilder));
+    b->compl_bufs=NULL;
+    b->curr_buf=Autoarr_create(int8,BL_C,BL_L);
+    return b;
 }
 
 void StringBuilder_free(StringBuilder* b){
-    Autoarr_free(b);
+    if(b->compl_bufs) Autoarr_free(b->compl_bufs);
+    Autoarr_free(b->curr_buf);
+    free(b);
 }
 
-void StringBuilder_pop(StringBuilder* b){
-    Autoarr_pop(b);
+string StringBuilder_build(StringBuilder* b){
+    complete_buf(b);
+    uint32 len=0;
+    Autoarr_foreach(b->compl_bufs, cs, ({
+        len+=cs.length;
+    }));
+    string str= { .length=len, .ptr=malloc(len+1) };
+    str.ptr[len]='\0';
+    uint32 i=0;
+    Autoarr_foreach(b->compl_bufs, cs, ({
+        for(uint32 n=0;n<cs.length;n++)
+            str.ptr[i++]=cs.ptr[n];
+        free(cs.ptr);
+    }));
+    StringBuilder_free(b);
+    return str;
 }
 
+
+void StringBuilder_rmchar(StringBuilder* b){
+    if(b->curr_buf->block_length!=0)
+        Autoarr_pop(b->curr_buf)
+    else {
+        if(!b->compl_bufs) throw(ERR_NULLPTR);
+        string* lastcb=Autoarr_getptr(b->compl_bufs, (Autoarr_length(b->compl_bufs)-1));
+        lastcb->length--;
+    }
+}
+
+
 void StringBuilder_append_char(StringBuilder* b, char c){
-    Autoarr_add(b,c);
+    try_complete_buf(b);
+    Autoarr_add(b->curr_buf,c);
+}
+
+
+void StringBuilder_append_string(StringBuilder* b, string s){
+    complete_buf(b);
+    Autoarr_add(b->compl_bufs, string_copy(s));
 }
 
 void StringBuilder_append_cptr(StringBuilder* b, char* s){
-    char c;
-    while((c=*s++))
-        Autoarr_add(b,c);
+    string str={
+        .ptr=s, 
+        .length=cptr_length(s)
+    };
+    StringBuilder_append_string(b,str);
 }
 
-void StringBuilder_append_string(StringBuilder* b, string s){
-    while(s.length>0){
-        Autoarr_add(b,*s.ptr++);
-        s.length--;
-    }
+void curr_buf_add_string(StringBuilder* b, string s){
+    for(uint32 i=0; i<s.length; i++)
+        Autoarr_add(b->curr_buf,s.ptr[i]);
 }
 
 void StringBuilder_append_int64(StringBuilder* b, int64 a){
+    try_complete_buf(b);
     uint8 i=0;
     if(a==0){
-        Autoarr_add(b,'0');
+        Autoarr_add(b->curr_buf,'0');
         return;
     }
     else if(a<0){
-        Autoarr_add(b,'-');
+        Autoarr_add(b->curr_buf,'-');
         a=-a;
     }
     char buf[24];
@@ -45,14 +112,15 @@ void StringBuilder_append_int64(StringBuilder* b, int64 a){
         a/=10;
     }
     string rev=string_reverse((string){buf,i});
-    StringBuilder_append_string(b,rev);
+    curr_buf_add_string(b,rev);
     free(rev.ptr);
 }
 
 void StringBuilder_append_uint64(StringBuilder* b, uint64 a){
+    try_complete_buf(b);
     uint8 i=0;
     if(a==0){
-        Autoarr_add(b,'0');
+        Autoarr_add(b->curr_buf,'0');
         return;
     }
     char buf[24];
@@ -61,24 +129,17 @@ void StringBuilder_append_uint64(StringBuilder* b, uint64 a){
         a/=10;
     }
     string rev=string_reverse((string){buf,i});
-    StringBuilder_append_string(b,rev);
+    curr_buf_add_string(b,rev);
     free(rev.ptr);
 }
 
-void StringBuilder_append_double(StringBuilder* b, double a){
+void StringBuilder_append_float64(StringBuilder* b, double a){
+    try_complete_buf(b);
     char buf[32];
     IFWIN(
         sprintf_s(buf,32,"%lf",a),
         sprintf(buf,"%lf",a)
     );
     StringBuilder_append_cptr(b,buf);
-}
-
-char* StringBuilder_build(StringBuilder* b){
-    uint32 len=Autoarr_length(b);
-    char* str=malloc(len+1);
-    str[len]=0;
-    for(uint32 i=0;i<len;i++)
-        str[i]=Autoarr_get(b,i);
-    return str;
+    curr_buf_add_string(b, (string){.ptr=buf, .length=cptr_length(buf)});
 }
diff --git a/String/StringBuilder.h b/String/StringBuilder.h
index 6cdac39..d1ed61f 100644
--- a/String/StringBuilder.h
+++ b/String/StringBuilder.h
@@ -7,18 +7,28 @@ extern "C" {
 #include "../Autoarr/Autoarr.h"
 #include "../String/string.h"
 
-typedef Autoarr(int8) StringBuilder;
+declare_Autoarr(string)
 
-StringBuilder* StringBuilder_create(uint16 max_blocks_count, uint16 max_block_length);
+typedef struct StringBuilder{
+	Autoarr(string)* compl_bufs;
+	Autoarr(int8)* curr_buf;
+} StringBuilder;
+
+StringBuilder* StringBuilder_create(void);
 void StringBuilder_free(StringBuilder* b);
-void StringBuilder_pop(StringBuilder* b);
+// Joins all strings from compl_bufs.
+// Returns zero-terminated string.
+// No need to call string_extract()!
+// Frees StringBuilder.
+string StringBuilder_build(StringBuilder* b);
+// removes last char
+void StringBuilder_rmchar(StringBuilder* b);
 void StringBuilder_append_char(StringBuilder* b, char c);
 void StringBuilder_append_cptr(StringBuilder* b, char* s);
 void StringBuilder_append_string(StringBuilder* b, string s);
 void StringBuilder_append_int64(StringBuilder* b, int64 a);
 void StringBuilder_append_uint64(StringBuilder* b, uint64 a);
-void StringBuilder_append_double(StringBuilder* b, double a);
-char* StringBuilder_build(StringBuilder* b);
+void StringBuilder_append_float64(StringBuilder* b, double a);
 
 #if __cplusplus
 }
diff --git a/String/string.c b/String/string.c
index 511fa2b..80699e4 100644
--- a/String/string.c
+++ b/String/string.c
@@ -1,7 +1,7 @@
 #include "../String/string.h"
 
 // copies str content to new char pointer value (adding '\0' at the end)
-char* string_cpToCptr(string str){
+char* string_extract(string str){
     if(str.length==0) return NULL;
     char* cptr=malloc(str.length*sizeof(char)+1);
     cptr[str.length]=0;
@@ -10,15 +10,15 @@ char* string_cpToCptr(string str){
     return cptr;
 }
 
-// copies cptr content (excluding '\0' at the end) to new string
-string string_cpFromCharPtr(char* cptr){
-    if(!cptr) return stringNull;
-    string str;
-    str.length=cptr_length(cptr)-1;
-    str.ptr=malloc(str.length);
-    for(uint32 i=0;i<str.length;i++)
-        str.ptr[i]=cptr[i];
-    return str;
+// copies src.ptr content to new string
+string string_copy(string src){
+    if(!src.ptr) return src;
+    string nstr;
+    nstr.length=src.length;
+    nstr.ptr=malloc(nstr.length);
+    for(uint32 i=0;i<nstr.length;i++)
+        nstr.ptr[i]=src.ptr[i];
+    return nstr;
 }
 
 // compares two strings, NullPtr-friendly
diff --git a/String/string.h b/String/string.h
index 43c60b7..e2076ee 100644
--- a/String/string.h
+++ b/String/string.h
@@ -16,10 +16,10 @@ typedef struct string{
 static const string stringNull={NULL,0};
 
 // copies str content to new char pointer value (adding '\0' at the end)
-char* string_cpToCptr(string str);
+char* string_extract(string str);
 
-// copies cptr content (excluding '\0' at the end) to new string
-string string_cpFromCharPtr(char* cptr);
+// copies src.ptr content to new string
+string string_copy(string src);
 
 // compares two strings, NullPtr-friendly
 bool string_compare(string str0, string str1);
diff --git a/base/cptr.c b/base/cptr.c
index 75a0ed7..210dd84 100644
--- a/base/cptr.c
+++ b/base/cptr.c
@@ -1,16 +1,16 @@
 #include "base.h"
 
-// returns length of string (including \0)
+// returns length of char buffer (without \0)
 uint32 cptr_length(char* str){
     uint32 len=0;
     while(*(str++)) len++;
-    return ++len;
+    return len;
 }
 
 // allocates new char[] and copies src there
 char* cptr_copy(char* src){
     uint32 len=cptr_length(src);
-    char* dst=malloc(len*sizeof(char));
+    char* dst=malloc(len+1);
     while(len-->0)
         dst[len]=src[len];
     return dst;
diff --git a/base/cptr.h b/base/cptr.h
index 50cd173..ccce381 100644
--- a/base/cptr.h
+++ b/base/cptr.h
@@ -6,7 +6,7 @@ extern "C" {
 
 #include "types.h"
 
-// returns length of string (including \0)
+// returns length of char buffer (without \0)
 uint32 cptr_length(char* str);
 
 // allocates new char[] and copies src there
diff --git a/tests/test_string.c b/tests/test_string.c
index 1a8a523..90110f6 100644
--- a/tests/test_string.c
+++ b/tests/test_string.c
@@ -5,12 +5,10 @@ void test_string(){
     optime(__func__,1,({
         printf("\e[96m-------------[test_string]-------------\n");
         char c[]="0123456789abcdef";
-        string s=string_cpFromCharPtr(c);
-        printf("\e[92m\"%s\" \e[94m-> string_cpFromCharPtr()\n",c);
-        if(s.length!=16) throw("string created with incorrect length");
-        char* p=string_cpToCptr(s);
-        printf("\e[94mstring_cpToCptr() -> \e[92m\"%s\"\n",p);
+        string s={.ptr=c, .length=cptr_length(c)};
+        if(s.length!=sizeof(c)-1) throw("string created with incorrect length");
+        char* p=string_extract(s);
+        printf("\e[94mstring_extract() -> \e[92m\"%s\"\n",p);
         free(p);
-        free(s.ptr);
     }));
 }
\ No newline at end of file