diff --git a/src/built_ins.cpp b/src/built_ins.cpp
index 396859b..60af1ea 100644
--- a/src/built_ins.cpp
+++ b/src/built_ins.cpp
@@ -29,9 +29,7 @@ proc lisp_object_equal(Lisp_Object* n1, Lisp_Object* n2) -> bool {
         create_error(Error_Type::Not_Yet_Implemented, n1->sourceCodeLocation);
         return false;
     case Lisp_Object_Type::String:
-        return string_equal(
-            n1->value.string->value,
-            n2->value.string->value);
+        return string_equal(n1->value.string, n2->value.string);
     case Lisp_Object_Type::Symbol:
         return string_equal(
             n1->value.symbol->identifier,
@@ -270,8 +268,8 @@ proc built_in_exponentiate(Lisp_Object* arguments, Environment* env) -> Lisp_Obj
 }
 
 
-proc built_in_load(const char* file_name, Environment* env) -> Lisp_Object* {
-    char* file_content = read_entire_file(file_name);
+proc built_in_load(String* file_name, Environment* env) -> Lisp_Object* {
+    char* file_content = read_entire_file(Memory::get_c_str(file_name));
     if (file_content) {
         Lisp_Object* result = Memory::create_lisp_object_nil();
         Lisp_Object_Array_List* program;
@@ -670,7 +668,7 @@ proc load_built_ins_into_environment(Environment* env) -> void {
             arguments = arguments->value.pair->rest;
             // if there is a docstring, use it
             if (arguments->value.pair->first->type == Lisp_Object_Type::String) {
-                function->docstring = arguments->value.pair->first->value.string->value;
+                function->docstring = arguments->value.pair->first->value.string;
                 arguments = arguments->value.pair->rest;
             } else {
                 function->docstring = nullptr;
@@ -720,7 +718,7 @@ proc load_built_ins_into_environment(Environment* env) -> void {
             arguments = arguments->value.pair->rest;
             // if there is a docstring, use it
             if (arguments->value.pair->first->type == Lisp_Object_Type::String) {
-                function->docstring = arguments->value.pair->first->value.string->value;
+                function->docstring = arguments->value.pair->first->value.string;
                 arguments = arguments->value.pair->rest;
             } else {
                 function->docstring = nullptr;
@@ -876,29 +874,33 @@ proc load_built_ins_into_environment(Environment* env) -> void {
                     Lisp_Object* fun = eval_expr(arguments->value.pair->first, env);
 
                     if (fun->value.function->docstring)
-                        printf("Docstring:\n==========\n%s\n\n", fun->value.function->docstring);
+                        printf("Docstring:\n==========\n%s\n\n", Memory::get_c_str(fun->value.function->docstring));
                     else
                         printf("No docstring avaliable\n");
 
                     printf("Arguments:\n==========\n");
                     printf("Postitional: {");
                     if (fun->value.function->positional_arguments->next_index != 0) {
-                        printf("%s", fun->value.function->positional_arguments->identifiers[0]);
+                        printf("%s",
+                               Memory::get_c_str(fun->value.function->positional_arguments->identifiers[0]));
                         for (int i = 1; i < fun->value.function->positional_arguments->next_index; ++i) {
-                            printf(", %s", fun->value.function->positional_arguments->identifiers[i]);
+                            printf(", %s",
+                                   Memory::get_c_str(fun->value.function->positional_arguments->identifiers[i]));
                         }
                     }
                     printf("}\n");
                     printf("Keyword:     {");
                     if (fun->value.function->keyword_arguments->next_index != 0) {
-                        printf("%s", fun->value.function->keyword_arguments->identifiers[0]);
+                        printf("%s",
+                               Memory::get_c_str(fun->value.function->keyword_arguments->identifiers[0]));
                         if (fun->value.function->keyword_arguments->values->data[0]) {
                             printf(" (");
                             print(fun->value.function->keyword_arguments->values->data[0]);
                             printf(")");
                         }
                         for (int i = 1; i < fun->value.function->keyword_arguments->next_index; ++i) {
-                            printf(", %s", fun->value.function->keyword_arguments->identifiers[i]);
+                            printf(", %s",
+                                   Memory::get_c_str(fun->value.function->keyword_arguments->identifiers[i]));
                             if (fun->value.function->keyword_arguments->values->data[i]) {
                                 printf(" (");
                                 print(fun->value.function->keyword_arguments->values->data[i]);
@@ -909,7 +911,8 @@ proc load_built_ins_into_environment(Environment* env) -> void {
                     printf("}\n");
                     printf("Rest:        {");
                     if (fun->value.function->rest_argument)
-                        printf("%s", fun->value.function->rest_argument);
+                        printf("%s",
+                               Memory::get_c_str(fun->value.function->rest_argument));
                     printf("}\n");
 
                 }
@@ -948,7 +951,9 @@ proc load_built_ins_into_environment(Environment* env) -> void {
                 print(evaluated_arguments->value.pair->first);
             }
             char* line = read_line();
-            return Memory::create_lisp_object_string(line, (int)strlen(line));
+            String* strLine = Memory::create_string(line);
+            free(line);
+            return Memory::create_lisp_object_string(strLine);
         });
     defun("exit", cLambda {
             try {
@@ -1012,8 +1017,7 @@ proc load_built_ins_into_environment(Environment* env) -> void {
 
             Lisp_Object* result;
             try {
-                result = built_in_load(
-                    evaluated_arguments->value.pair->first->value.string->value, env);
+                result = built_in_load(evaluated_arguments->value.pair->first->value.string, env);
             }
             return result;
 
@@ -1070,7 +1074,7 @@ proc load_built_ins_into_environment(Environment* env) -> void {
                 report_error(Error_Type::Type_Missmatch);
             }
 
-            return Memory::create_lisp_object_symbol(_strdup(source->value.string->value));
+            return Memory::create_lisp_object_symbol(Memory::duplicate_string(source->value.string));
         });
     defun("symbol->string", cLambda {
             try {
@@ -1086,9 +1090,7 @@ proc load_built_ins_into_environment(Environment* env) -> void {
             if (source->type != Lisp_Object_Type::Symbol) {
                 report_error(Error_Type::Type_Missmatch);
             }
-
-            // TODO(Felix): this is not really fast what we are doing here:
-            return Memory::create_lisp_object_string(_strdup(source->value.symbol->identifier), (int)strlen(source->value.symbol->identifier));
+            return Memory::create_lisp_object_string(Memory::duplicate_string(source->value.symbol->identifier));
         });
     defun("concat-strings", cLambda {
             try {
@@ -1114,18 +1116,17 @@ proc load_built_ins_into_environment(Environment* env) -> void {
 
             head = evaluated_arguments;
 
-            char* resulting_string = (char*)malloc(resulting_string_len * sizeof(char)) + 1;
+            String* resulting_string = Memory::create_string("", resulting_string_len);
             int index_in_string = 0;
 
             while (head->type == Lisp_Object_Type::Pair) {
-                strcpy(resulting_string+index_in_string, head->value.pair->first->value.string->value);
+                strcpy((&resulting_string->data)+index_in_string,
+                       Memory::get_c_str(head->value.pair->first->value.string));
                 index_in_string += head->value.pair->first->value.string->length;
                 head = head->value.pair->rest;
             }
 
-            resulting_string[index_in_string] = '\0';
-
-            return Memory::create_lisp_object_string(resulting_string, resulting_string_len);
+            return Memory::create_lisp_object_string(resulting_string);
         });
 
 #undef report_error
diff --git a/src/env.cpp b/src/env.cpp
index e814264..35b377e 100644
--- a/src/env.cpp
+++ b/src/env.cpp
@@ -11,14 +11,14 @@ proc define_symbol(Lisp_Object* symbol, Lisp_Object* value, Environment* env) ->
         env->values = (Lisp_Object**)realloc(env->values, env->capacity * sizeof(Lisp_Object*));
     }
 
-    env->keys  [env->next_index] = symbol->value.symbol->identifier;
+    env->keys  [env->next_index] = Memory::get_c_str(symbol->value.symbol->identifier);
     env->values[env->next_index] = value;
     ++env->next_index;
 }
 
 proc lookup_symbol_in_this_envt(Symbol* sym, Environment* env) -> Lisp_Object* {
     for (int i = env->next_index - 1; i >= 0; --i)
-        if (string_equal(env->keys[i], sym->identifier))
+        if (string_equal(env->keys[i], Memory::get_c_str(sym->identifier)))
             return env->values[i];
     return nullptr;
 }
@@ -38,15 +38,15 @@ proc lookup_symbol(Lisp_Object* node, Environment* env) -> Lisp_Object* {
             return result;
     }
 
-    if (string_equal(sym->identifier, "nil")) {
+    if (string_equal(Memory::get_c_str(sym->identifier), "nil")) {
         return Memory::create_lisp_object_nil();
     }
-    if (string_equal(sym->identifier, "t")) {
+    if (string_equal(Memory::get_c_str(sym->identifier), "t")) {
         return Memory::create_lisp_object_t();
     }
 
     create_error(Error_Type::Symbol_Not_Defined, node->sourceCodeLocation);
-    printf("%s\n", sym->identifier);
+    printf("%s\n", Memory::get_c_str(sym->identifier));
     return nullptr;
 }
 
diff --git a/src/eval.cpp b/src/eval.cpp
index 97b8d39..4a37b8f 100644
--- a/src/eval.cpp
+++ b/src/eval.cpp
@@ -18,7 +18,7 @@ proc apply_arguments_to_function(Lisp_Object* arguments, Function* function) ->
         arguments = arguments->value.pair->rest;
     }
 
-    String_Array_List* read_in_keywords = create_String_array_list(16);
+    String_Array_List* read_in_keywords = create_String_array_list();
 
     if (arguments->type == Lisp_Object_Type::Nil)
         goto checks;
@@ -86,7 +86,7 @@ proc apply_arguments_to_function(Lisp_Object* arguments, Function* function) ->
   checks:
     // check if all necessary keywords have been read in
     for (int i = 0; i < function->keyword_arguments->next_index; ++i) {
-        char* defined_keyword = function->keyword_arguments->identifiers[i];
+        String* defined_keyword = function->keyword_arguments->identifiers[i];
         bool was_set = false;
         for (int j = 0; j < read_in_keywords->next_index; ++j) {
             if (string_equal(
@@ -439,12 +439,13 @@ proc interprete_file (char* file_name) -> Lisp_Object* {
     load_built_ins_into_environment(env);
 
     try {
-        built_in_load("pre.slime", env);
+        built_in_load(Memory::create_string("pre.slime"), env);
     }
 
     Lisp_Object_Array_List* program;
     try {
-        program = Parser::parse_program(file_name, file_content);
+        program = Parser::parse_program(
+            Memory::create_string(file_name), file_content);
     }
 
     Lisp_Object* result = Memory::create_lisp_object_nil();
@@ -466,8 +467,8 @@ proc interprete_stdin() -> void {
 
     char* line;
 
-    built_in_load("pre.slime", env);
-    built_in_load("test.slime", env);
+    built_in_load(Memory::create_string("pre.slime"), env);
+    built_in_load(Memory::create_string("test.slime"), env);
 
     if (error) {
         log_error();
@@ -479,6 +480,7 @@ proc interprete_stdin() -> void {
         printf(">");
         line = read_expression();
         parsed = Parser::parse_single_expression(line);
+        free(line);
         if (error) {
             log_error();
             delete_error();
diff --git a/src/forward_decls.cpp b/src/forward_decls.cpp
index f3b0e61..3653a7c 100644
--- a/src/forward_decls.cpp
+++ b/src/forward_decls.cpp
@@ -5,3 +5,4 @@ proc is_truthy (Lisp_Object*, Environment*) -> bool;
 proc list_length(Lisp_Object*) -> int;
 proc load_built_ins_into_environment(Environment*) -> void;
 proc parse_argument_list(Lisp_Object*, Function*) -> void;
+proc create_error(Error_Type type, Source_Code_Location* location) -> void;
diff --git a/src/io.cpp b/src/io.cpp
index 02a917c..4156450 100644
--- a/src/io.cpp
+++ b/src/io.cpp
@@ -8,6 +8,18 @@ proc string_equal(const char input[], const char check[]) -> bool {
     return true;
 }
 
+proc string_equal(String* str, const char check[]) -> bool {
+    return string_equal(Memory::get_c_str(str), check);
+}
+
+proc string_equal(const char check[], String* str) -> bool {
+    return string_equal(Memory::get_c_str(str), check);
+}
+
+proc string_equal(String* str1, String* str2) -> bool {
+    return string_equal(Memory::get_c_str(str1), Memory::get_c_str(str2));
+}
+
 proc get_nibble(char c) -> char {
     if (c >= 'A' && c <= 'F')
         return (c - 'a') + 10;
@@ -67,7 +79,7 @@ proc unescape_string(char* in) -> bool {
     return true;
 }
 
-proc read_entire_file (const char* filename) -> char* {
+proc read_entire_file(char* filename) -> char* {
     char *fileContent = nullptr;
     FILE *fp = fopen(filename, "r");
     if (fp) {
@@ -106,7 +118,8 @@ proc read_entire_file (const char* filename) -> char* {
 }
 
 proc read_expression() -> char* {
-    char* line = (char*)malloc(100), * linep = line;
+    char* line = (char*)malloc(100);
+    char* linep = line;
     size_t lenmax = 100, len = lenmax;
     int c;
 
@@ -132,20 +145,20 @@ proc read_expression() -> char* {
             linep = linen;
         }
 
-        line++;
-        if((*line = (char)c) == '(')
+        *line = (char)c;
+        if(*line == '(')
             ++nesting;
-        else if((*line = (char)c) == ')')
+        else if(*line == ')')
             --nesting;
-        else if((*line = (char)c) == '\n')
+        else if(*line == '\n')
             if (nesting == 0)
                 break;
+        line++;
     }
     (*line)--; // we dont want the \n actually
     *line = '\0';
-    // BUG(Felix): Why do we have to add 1 here?
 
-    return linep + 1;
+    return linep;
 }
 
 proc read_line() -> char* {
@@ -175,19 +188,20 @@ proc read_line() -> char* {
             linep = linen;
         }
 
-        line++;
-        if((*line = (char)c) == '(')
+        *line = (char)c;
+        if(*line == '(')
             ++nesting;
-        else if((*line = (char)c) == ')')
+        else if(*line == ')')
             --nesting;
-        else if((*line = (char)c) == '\n')
+        else if(*line == '\n')
             if (nesting == 0)
                 break;
+        line++;
     }
     (*line)--; // we dont want the \n actually
     *line = '\0';
-    // BUG(Felix): Why do we have to add 1 here?
-    return linep + 1;
+    
+    return linep;
 }
 
 
@@ -225,13 +239,13 @@ proc print(Lisp_Object* node) -> void {
         printf("%f", node->value.number->value);
     } break;
     case (Lisp_Object_Type::String): {
-        printf("\"%s\"", node->value.string->value);
+        printf("\"%s\"", Memory::get_c_str(node->value.string));
     } break;
     case (Lisp_Object_Type::Symbol): {
-        printf("%s", node->value.symbol->identifier);
+        printf("%s", Memory::get_c_str(node->value.symbol->identifier));
     } break;
     case (Lisp_Object_Type::Keyword): {
-        printf(":%s", node->value.keyword->identifier);
+        printf(":%s", Memory::get_c_str(node->value.keyword->identifier));
     } break;
     case (Lisp_Object_Type::Function): {
         if (node->value.function->type == Function_Type::Lambda)
@@ -286,13 +300,13 @@ proc fprint(FILE* f, Lisp_Object* node) -> void {
         fprintf(f, "%f", node->value.number->value);
     } break;
     case (Lisp_Object_Type::String): {
-        fprintf(f, "\"%s\"", node->value.string->value);
+        fprintf(f, "\"%s\"", Memory::get_c_str(node->value.string));
     } break;
     case (Lisp_Object_Type::Symbol): {
-        fprintf(f, "%s", node->value.symbol->identifier);
+        fprintf(f, "%s", Memory::get_c_str(node->value.symbol->identifier));
     } break;
     case (Lisp_Object_Type::Keyword): {
-        fprintf(f, ":%s", node->value.keyword->identifier);
+        fprintf(f, ":%s", Memory::get_c_str(node->value.keyword->identifier));
     } break;
     case (Lisp_Object_Type::Function): {
         if (node->value.function->type == Function_Type::Lambda)
@@ -337,7 +351,7 @@ proc fprint(FILE* f, Lisp_Object* node) -> void {
 proc print_error_location() -> void {
     if (error->location) {
         printf("%s (line %d, position %d)",
-               error->location->file,
+               Memory::get_c_str(error->location->file),
                error->location->line,
                error->location->column);
     } else {
diff --git a/src/lisp_object.cpp b/src/lisp_object.cpp
index 0876ce3..cc2d5bb 100644
--- a/src/lisp_object.cpp
+++ b/src/lisp_object.cpp
@@ -1,4 +1,4 @@
-proc create_source_code_location(const char* file, int line, int col) -> Source_Code_Location* {
+proc create_source_code_location(String* file, int line, int col) -> Source_Code_Location* {
     if (!file)
         return nullptr;
 
@@ -26,23 +26,23 @@ proc Lisp_Object_Type_to_string(Lisp_Object_Type type) -> const char* {
 
 proc create_positional_argument_list(int initial_capacity) -> Positional_Arguments* {
     Positional_Arguments* ret = new(Positional_Arguments);
-    ret->identifiers = (char**)malloc(initial_capacity * sizeof(char*));
+    ret->identifiers = (String**)malloc(initial_capacity * sizeof(String*));
     ret->next_index = 0;
     ret->length = initial_capacity;
     return ret;
 }
 
-proc append_to_positional_argument_list(Positional_Arguments* args, char* identifier) -> void {
+proc append_to_positional_argument_list(Positional_Arguments* args, String* identifier) -> void {
     if (args->next_index == args->length) {
         args->length *= 2;
-        args->identifiers = (char**)realloc(args->identifiers, args->length * sizeof(char*));
+        args->identifiers = (String**)realloc(args->identifiers, args->length * sizeof(String*));
     }
     args->identifiers[args->next_index++] = identifier;
 }
 
 proc create_keyword_argument_list(int initial_capacity) -> Keyword_Arguments* {
     Keyword_Arguments* ret = new(Keyword_Arguments);
-    ret->identifiers = (char**)malloc(initial_capacity * sizeof(char*));
+    ret->identifiers = (String**)malloc(initial_capacity * sizeof(String*));
     ret->values = create_Lisp_Object_array_list(initial_capacity);
     ret->next_index = 0;
     ret->length = initial_capacity;
@@ -50,12 +50,12 @@ proc create_keyword_argument_list(int initial_capacity) -> Keyword_Arguments* {
 }
 
 proc append_to_keyword_argument_list(Keyword_Arguments* args,
-                                     char* identifier,
-                                     struct Lisp_Object* default_value) -> void
+                                     String* identifier,
+                                     Lisp_Object* default_value) -> void
 {
     if (args->next_index == args->length) {
         args->length *= 2;
-        args->identifiers = (char**)realloc(args->identifiers, args->length * sizeof(char*));
+        args->identifiers = (String**)realloc(args->identifiers, args->length * sizeof(String*));
     }
 
     args->identifiers[args->next_index++] = identifier;
diff --git a/src/memory.cpp b/src/memory.cpp
index 0a4447a..e85725c 100644
--- a/src/memory.cpp
+++ b/src/memory.cpp
@@ -1,40 +1,100 @@
 namespace Memory {
 
-    constexpr int maxLispObjects = 4096 * 1024; // == 98304kb == 96mb
-    Int_Array_List* freeSpots;
-    Lisp_Object* memory;
-    int nextFreeSpot = 0;
-
-    proc init() -> void {
-        memory = (Lisp_Object*)malloc(maxLispObjects * sizeof(Lisp_Object));
-        freeSpots = create_Int_array_list();
+    // ------------------
+    //   lisp_object
+    // ------------------
+    constexpr int object_memory_size = 4096 * 1024; // == 98304kb == 96mb
+    Int_Array_List* free_spots_in_object_memory;
+    Lisp_Object* object_memory;
+    int next_index_in_object_memory = 0;
+
+    // ------------------
+    //   strings
+    // ------------------
+    constexpr int string_memory_size = 4096 * 1024; // == 98304kb == 96mb
+    // free_spots_in_string_memory is an arraylist of pointers into
+    // the string_memory, where dead String objects live (which give
+    // information about their size)
+    Void_Ptr_Array_List* free_spots_in_string_memory;
+    String* string_memory;
+    String* next_free_spot_in_string_memory;
+
+    proc init() {
+        free_spots_in_object_memory = create_Int_array_list();
+        free_spots_in_string_memory = create_Void_Ptr_array_list();
+
+        object_memory = (Lisp_Object*)malloc(object_memory_size * sizeof(Lisp_Object));
+        string_memory = (String*)malloc(object_memory_size * sizeof(Lisp_Object));
+
+        next_free_spot_in_string_memory = string_memory;
     }
 
-    proc print_status() -> void {
+    proc print_status() {
         printf("Memory Status:\n"
-               " - %f%% of the memory is used\n"
+               " - %f%% of the object_memory is used\n"
                " - %d of %d total Lisp_Objects are in use\n"
                " - %d holes in used memory (fragmentation)\n",
-               (1.0*nextFreeSpot - freeSpots->next_index)/maxLispObjects,
-               nextFreeSpot - freeSpots->next_index, maxLispObjects,
-               freeSpots->next_index);
+               (1.0*next_index_in_object_memory - free_spots_in_object_memory->next_index)/object_memory_size,
+               next_index_in_object_memory - free_spots_in_object_memory->next_index, object_memory_size,
+               free_spots_in_object_memory->next_index);
+
+        printf("Memory Status:\n"
+               " - %f%% of the string_memory is used\n"
+               " - %d holes in used memory (fragmentation)\n",
+               (1.0*(size_t)next_free_spot_in_string_memory - (size_t)string_memory)/string_memory_size,
+               free_spots_in_string_memory->next_index);
+    }
+
+    inline proc get_c_str(String* str) -> char* {
+        return &str->data;
+    }
+
+    proc create_string(const char* str, int len) -> String* {
+        // TODO(Felix): check the holes first, not just always append
+        // at the end
+
+        String* ret = next_free_spot_in_string_memory;
+        ret->length = len;
+        strcpy(&ret->data, str);
+
+        // now update the next_free_spot_in_string_memory pointer:
+        // overstrep the counter and the first char (thik of it as if
+        // we were overstepping the last ('\0') char) and then we only
+        // need to overstep 'len' more chars
+        next_free_spot_in_string_memory += 1;
+
+        // overstep the other chars
+        next_free_spot_in_string_memory = ((String*)((char*)next_free_spot_in_string_memory)+len);
+        return ret;
+    }
+
+    proc delete_string(String* str) {
+        append_to_Void_Ptr_array_list(free_spots_in_string_memory, (void*)str);
+    }
+
+    proc duplicate_string(String* str) -> String* {
+        return create_string(get_c_str(str), str->length);
+    }
+
+    proc create_string (const char* str) -> String* {
+        return create_string(str, (int)strlen(str));
     }
 
     proc create_lisp_object() -> Lisp_Object* {
         int index;
         // if we have no free spots then append at the end
-        if (freeSpots->next_index == 0) {
+        if (free_spots_in_object_memory->next_index == 0) {
             // if we still have space
-            if (maxLispObjects == nextFreeSpot) {
+            if (object_memory_size == next_index_in_object_memory) {
                 create_error(Error_Type::Out_Of_Memory, nullptr);
                 return nullptr;
             }
-            index = nextFreeSpot++;
+            index = next_index_in_object_memory++;
         } else {
             // else fill a free spot
-            index = freeSpots->data[freeSpots->next_index--];
+            index = free_spots_in_object_memory->data[free_spots_in_object_memory->next_index--];
         }
-        Lisp_Object* object = memory+index;
+        Lisp_Object* object = object_memory+index;
         object->sourceCodeLocation = nullptr;
         return object;
     }
@@ -61,31 +121,39 @@ namespace Memory {
         return node;
     }
 
-    proc create_lisp_object_string(char* str, int length) -> Lisp_Object* {
+    proc create_lisp_object_string(String* str) -> Lisp_Object* {
         Lisp_Object* node = create_lisp_object();
         node->type = Lisp_Object_Type::String;
-        node->value.string = new(String);
-        node->value.string->value = str;
-        node->value.string->length = length;
+        node->value.string = str;
         return node;
     }
 
-    proc create_lisp_object_symbol(const char* identifier) -> Lisp_Object* {
+    proc create_lisp_object_symbol(String* identifier) -> Lisp_Object* {
         Lisp_Object* node = create_lisp_object();
         node->type = Lisp_Object_Type::Symbol;
         node->value.symbol = new(Symbol);
-        node->value.symbol->identifier = (char*) identifier;
+        node->value.symbol->identifier = identifier;
         return node;
     }
 
-    proc create_lisp_object_keyword(const char* keyword) -> Lisp_Object* {
+    proc create_lisp_object_symbol(const char* identifier) -> Lisp_Object* {
+        return create_lisp_object_symbol(
+            Memory::create_string(identifier));
+    }
+
+    proc create_lisp_object_keyword(String* keyword) -> Lisp_Object* {
         Lisp_Object* node = create_lisp_object();
         node->type = Lisp_Object_Type::Keyword;
         node->value.keyword = new(Keyword);
-        node->value.keyword->identifier = (char*) keyword;
+        node->value.keyword->identifier = keyword;
         return node;
     }
 
+    proc create_lisp_object_keyword(const char* keyword) -> Lisp_Object* {
+        return create_lisp_object_keyword(
+            Memory::create_string(keyword));
+    }
+
     proc create_lisp_object_cfunction(std::function<Lisp_Object*(Lisp_Object*, Environment*)> function) -> Lisp_Object* {
         Lisp_Object* node = create_lisp_object();
         node->type = Lisp_Object_Type::CFunction;
@@ -132,5 +200,4 @@ namespace Memory {
         load_built_ins_into_environment(ret);
         return ret;
     }
-
 }
diff --git a/src/parse.cpp b/src/parse.cpp
index 4deeb31..af1c4a9 100644
--- a/src/parse.cpp
+++ b/src/parse.cpp
@@ -1,15 +1,8 @@
 namespace Parser {
 
-#define inject_scl(_ret)                                         \
-    _ret->sourceCodeLocation = new(Source_Code_Location);        \
-    _ret->sourceCodeLocation->file   = parser_file;              \
-    _ret->sourceCodeLocation->line   = parser_line;              \
-    _ret->sourceCodeLocation->column = parser_col
-
-    const char* parser_file;
+    String* parser_file;
     int parser_line;
     int parser_col;
-
     // NOTE(Felix): In this environment, the build in functions will
     // be loaded, and the macros will be stroed in form of
     // special-lambdas, that get executed in this environment at
@@ -28,6 +21,13 @@ namespace Parser {
         environment_for_macros = env;
     }
 
+    proc inject_scl(Lisp_Object* lo) -> void {
+        lo->sourceCodeLocation = new(Source_Code_Location);
+        lo->sourceCodeLocation->file   = parser_file;
+        lo->sourceCodeLocation->line   = parser_line;
+        lo->sourceCodeLocation->column = parser_col;
+    }
+
     void eat_comment_line(char* text, int* index_in_text) {
         // safety check if we are actually starting a comment here
         if (text[*index_in_text] != ';')
@@ -68,7 +68,7 @@ namespace Parser {
         } while (position_before != *index_in_text);
     }
 
-    char* read_atom(char* text, int* index_in_text) {
+    String* read_atom(char* text, int* index_in_text) {
         int atom_length = 0;
         while (text[*index_in_text+atom_length] != ' '  &&
                text[*index_in_text+atom_length] != ')'  &&
@@ -88,8 +88,9 @@ namespace Parser {
         text[*index_in_text+atom_length] = '\0';
 
         // get the atom
-        char* atom = (char*)malloc(atom_length*sizeof(char)+1); // plus null char
-        strcpy(atom, text+(*index_in_text));
+        String* ret = Memory::create_string("", atom_length);
+        // char* atom = (char*)malloc(atom_length*sizeof(char)+1); // plus null char
+        strcpy(&ret->data, text+(*index_in_text));
 
         // restore the original string
         text[*index_in_text+atom_length] = before;
@@ -98,14 +99,17 @@ namespace Parser {
         // ended
         *index_in_text += atom_length;
 
-        return atom;
+        return ret;
     }
 
     Lisp_Object* parse_number(char* text, int* index_in_text) {
         double number;
-        char* str_number = read_atom(text, index_in_text);
-        sscanf(str_number, "%lf", &number);
+        // TODO(Felix): parse the number direcrly from the string and
+        // dont create a String first
+        String* str_number = read_atom(text, index_in_text);
+        sscanf(Memory::get_c_str(str_number), "%lf", &number);
         Lisp_Object* ret = Memory::create_lisp_object_number(number);
+
         inject_scl(ret);
         return ret;
     }
@@ -114,15 +118,16 @@ namespace Parser {
         // we are now on the colon
         ++(*index_in_text);
         ++parser_col;
-        char* str_keyword = read_atom(text, index_in_text);
+        String* str_keyword = read_atom(text, index_in_text);
         Lisp_Object* ret = Memory::create_lisp_object_keyword(str_keyword);
+
         inject_scl(ret);
         return ret;
     }
 
     Lisp_Object* parse_symbol(char* text, int* index_in_text) {
         // we are now at the first char of the symbol
-        char* str_symbol = read_atom(text, index_in_text);
+        String* str_symbol = read_atom(text, index_in_text);
         Lisp_Object* ret = Memory::create_lisp_object_symbol(str_symbol);
         inject_scl(ret);
         return ret;
@@ -136,9 +141,8 @@ namespace Parser {
         // now we are at the first letter, if this is the closing '"' then
         // it's easy
         if (text[*index_in_text] == '"') {
-            char* str = new(char);
-            *str = '\0';
-            Lisp_Object* ret = Memory::create_lisp_object_string(str, 0);
+            Lisp_Object* ret = Memory::create_lisp_object_string(
+                Memory::create_string("", 0));
             inject_scl(ret);
 
             // plus one because we want to go after the quotes
@@ -158,7 +162,7 @@ namespace Parser {
         // we found the end of the string
         text[*index_in_text+string_length] = '\0';
 
-        char* string = (char*)malloc(string_length*sizeof(char)+1); // plus null char
+        String* string = Memory::create_string("", string_length);
 
         if (!unescape_string(text+(*index_in_text))) {
             create_error(
@@ -166,7 +170,7 @@ namespace Parser {
                 create_source_code_location(parser_file, parser_line, parser_col));
             return nullptr;
         }
-        strcpy(string, text+(*index_in_text));
+        strcpy(&string->data, text+(*index_in_text));
         /* manually copy to parse control sequences correctly */
         /* int temp_index = 0; */
         /* while (text+(temp_index+(*index_in_text)) != '\0') { */
@@ -179,7 +183,7 @@ namespace Parser {
         *index_in_text += string_length +1; // plus one because we want to
         // go after the quotes
 
-        Lisp_Object* ret = Memory::create_lisp_object_string(string, string_length);
+        Lisp_Object* ret = Memory::create_lisp_object_string(string);
         inject_scl(ret);
         return ret;
     }
@@ -371,7 +375,7 @@ namespace Parser {
                 arguments = arguments->value.pair->rest;
                 // if there is a docstring, use it
                 if (arguments->value.pair->first->type == Lisp_Object_Type::String) {
-                    function->docstring = arguments->value.pair->first->value.string->value;
+                    function->docstring = arguments->value.pair->first->value.string;
                     arguments = arguments->value.pair->rest;
                 } else {
                     function->docstring = nullptr;
@@ -437,7 +441,7 @@ namespace Parser {
     }
 
     Lisp_Object* parse_single_expression(char* text) {
-        parser_file = "stdin";
+        parser_file = Memory::create_string("stdin");
         parser_line = 1;
         parser_col = 1;
 
@@ -466,10 +470,10 @@ namespace Parser {
         return nullptr;
     }
 
-    void write_expanded_file(const char* file_name, Lisp_Object_Array_List* program) {
+    void write_expanded_file(String* file_name, Lisp_Object_Array_List* program) {
         const char* ext = ".expanded";
-        char* newName = (char*)calloc(4 + strlen(file_name), sizeof(char));
-        strcpy(newName, file_name);
+        char* newName = (char*)calloc(10 + file_name->length, sizeof(char));
+        strcpy(newName, Memory::get_c_str(file_name));
         strcat(newName, ext);
 
         FILE *f = fopen(newName, "w");
@@ -487,15 +491,15 @@ namespace Parser {
         }
 
         fclose(f);
+        free(newName);
     }
 
-    Lisp_Object_Array_List* parse_program(const char* file_name, char* text) {
-        parser_file = (char*)malloc(strlen(file_name) * sizeof(char) + 1);
-        strcpy((char *)parser_file, file_name);
+    Lisp_Object_Array_List* parse_program(String* file_name, char* text) {
+        parser_file = file_name;
         parser_line = 1;
         parser_col = 0;
 
-        Lisp_Object_Array_List* program = create_Lisp_Object_array_list(16);
+        Lisp_Object_Array_List* program = create_Lisp_Object_array_list();
 
         int index_in_text = 0;
 
@@ -526,6 +530,4 @@ namespace Parser {
 
         return program;
     }
-
-#undef inject_scl
 }
diff --git a/src/slime.h b/src/slime.h
index 920c7ab..c21751e 100644
--- a/src/slime.h
+++ b/src/slime.h
@@ -6,10 +6,10 @@
 #include "./defines.cpp"
 #include "./structs.cpp"
 #include "./forward_decls.cpp"
+#include "./memory.cpp"
 #include "./lisp_object.cpp"
 #include "./error.cpp"
 #include "./io.cpp"
-#include "./memory.cpp"
 #include "./env.cpp"
 #include "./parse.cpp"
 #include "./built_ins.cpp"
diff --git a/src/structs.cpp b/src/structs.cpp
index 1327612..a905f18 100644
--- a/src/structs.cpp
+++ b/src/structs.cpp
@@ -1,9 +1,11 @@
 struct Lisp_Object;
+struct String;
 struct Environment;
 
 define_array_list(Lisp_Object*, Lisp_Object);
-define_array_list(char*, String);
+define_array_list(String*, String);
 define_array_list(int, Int);
+define_array_list(void*, Void_Ptr);
 
 enum struct Lisp_Object_Type {
     Nil,
@@ -49,29 +51,29 @@ enum struct Log_Level {
     Debug,
 };
 
+struct String {
+    int length;
+    char data;
+};
+
 struct Source_Code_Location {
-    const char* file;
+    String* file;
     int line;
     int column;
 };
 
 struct Symbol {
-    char* identifier;
+    String* identifier;
 };
 
 struct Keyword {
-    char* identifier;
+    String* identifier;
 };
 
 struct Number {
     double value;
 };
 
-struct String {
-    int length;
-    char* value;
-};
-
 struct Pair {
     Lisp_Object* first;
     Lisp_Object* rest;
@@ -80,13 +82,13 @@ struct Pair {
 struct Positional_Arguments {
     // TODO(Felix) use Lisp_Object_symbols here instead, so we don't have
     // to convert them to strings and back to symbols
-    char** identifiers;
+    String** identifiers; // Array of Pointers to String
     int next_index;
     int length;
 };
 
 struct Keyword_Arguments {
-    char** identifiers;
+    String** identifiers; // Array of Pointers to String
     // NOTE(Felix): values[i] will be nullptr if no defalut value was
     // declared for key identifiers[i]
     Lisp_Object_Array_List* values;
@@ -96,11 +98,11 @@ struct Keyword_Arguments {
 
 struct Function {
     Function_Type type;
-    char*  docstring;
+    String*  docstring;
     Positional_Arguments* positional_arguments;
     Keyword_Arguments*    keyword_arguments;
     // rest_argument will be nullptr if no rest argument is declared
-    char*                 rest_argument;
+    String*      rest_argument;
     Lisp_Object* body; // implicit prog
     Environment* parent_environment; // we are doing closures now!!
 };
diff --git a/src/testing.cpp b/src/testing.cpp
index af4eb29..4099533 100644
--- a/src/testing.cpp
+++ b/src/testing.cpp
@@ -50,7 +50,7 @@
 
 #define assert_equal_string(variable, value)                            \
     if (!string_equal(variable, value)) {                               \
-        print_assert_equal_fail(variable, value, char*, "%s");          \
+        print_assert_equal_fail(&variable->data, value, char*, "%s");    \
         return fail;                                                    \
     }
 
@@ -108,7 +108,7 @@ proc test_eval_operands() -> testresult {
 
     assert_equal_type(operands, Lisp_Object_Type::Pair);
     assert_equal_type(operands->value.pair->first, Lisp_Object_Type::String);
-    assert_equal_string(operands->value.pair->first->value.string->value, "okay");
+    assert_equal_string(operands->value.pair->first->value.string, "okay");
 
     operands = operands->value.pair->rest;
 
@@ -144,7 +144,7 @@ proc test_parse_atom() -> testresult {
 
     result = Parser::parse_atom(string, &index_in_text);
     assert_equal_type(result, Lisp_Object_Type::String);
-    assert_equal_string(result->value.string->value, "asd");
+    assert_equal_string(result->value.string, "asd");
 
     // test keywords
     ++index_in_text;