diff --git a/src/compiler/Compiler.c b/src/compiler/Compiler.c
new file mode 100644
index 0000000..d15aa5b
--- /dev/null
+++ b/src/compiler/Compiler.c
@@ -0,0 +1,140 @@
+#include "Compiler_internal.h"
+
+
+void Compiler_init(Compiler* cmp){
+    memset(cmp, 0, sizeof(Compiler));
+    cmp->state = CompilerState_Initial;
+    cmp->tokens = List_Token_alloc(4096);
+    cmp->line_lengths = List_u32_alloc(1024);
+}
+
+void Compiler_free(Compiler* cmp){
+    free(cmp->code);
+    free(cmp->tokens.data);
+    free(cmp->line_lengths.data);
+}
+
+CodePos Compiler_getLineAndColumn(Compiler* cmp, u32 pos){
+    u32 prev_lines_len = 0;
+    if(pos >= cmp->code_len)
+        return CodePos_create(0, 0);
+    
+    for(u32 i = 0; i < cmp->line_lengths.len; i++){
+        u32 line_len = cmp->line_lengths.data[i];
+        if(prev_lines_len + line_len > pos)
+            return CodePos_create(i + 1, pos + 1 - prev_lines_len);
+        prev_lines_len += line_len;
+    }
+
+    return CodePos_create(0, 0);
+}
+
+void _Compiler_setError(Compiler* cmp, cstr context, cstr format, ...){
+    // happens at the end of file
+    if(cmp->pos >= cmp->code_len)
+        cmp->pos = cmp->code_len - 1;
+    char position_str[32];
+    CodePos code_pos = Compiler_getLineAndColumn(cmp, cmp->pos);
+    sprintf(position_str, "[at %u:%u][", code_pos.line, code_pos.column);
+    char* real_format = strcat_malloc(position_str, context, "] ", format);
+    va_list argv;
+    va_start(argv, format);
+    char* NULLABLE(buf) = vsprintf_malloc(512, real_format, argv);
+    va_end(argv);
+    free(real_format);
+    if(buf == NULL){
+        buf = malloc(16);
+        strcpy(buf, "SPRINTF FAILED");
+    }
+    cmp->state = CompilerState_Error;
+    cmp->error_message = buf;
+}
+
+#define setError(FORMAT, ...) {\
+    Compiler_setError(cmp, FORMAT, ##__VA_ARGS__);\
+}
+
+static bool compileFile(Compiler* cmp, FILE* f){
+    returnErrorIf_auto(cmp->state != CompilerState_Parsing);
+    cmp->state = CompilerState_Compiling;
+
+    return true;
+}
+
+bool Compiler_compile(Compiler* cmp, cstr source_file_name, cstr out_file_name, bool debug){
+    FILE* f = fopen(source_file_name, "rb");
+    if(f == NULL)
+        returnError("ERROR: can't open file '%s'", source_file_name);
+    
+    List_u8 buf = List_u8_alloc(64 * 1024);
+    int ret;
+    while((ret = fgetc(f)) != EOF) {
+        List_u8_push(&buf, ret);
+    }
+    if(ferror(f)){
+        free(buf.data);
+        fclose(f);
+        returnError("can't read file '%s'", source_file_name);
+    }
+    fclose(f);
+
+    if(buf.len == 0){
+        free(buf.data);
+        fclose(f);
+        returnError("soucre file is empty");
+    }
+
+    cmp->code = (char*)buf.data;
+    cmp->code_len = buf.len;
+    List_u8_push(&buf, 0);
+
+    f = fopen(out_file_name, "wb");
+    if(f == NULL){
+        free(buf.data);
+        returnError("ERROR: can't open file '%s'", out_file_name);
+    }
+
+    if(debug){
+        printf("----------------------------------[%s]---------------------------------\n", source_file_name);
+        fputs(cmp->code, stdout);
+        fputc('\n', stdout);
+    }
+    
+    bool success = Compiler_lex(cmp);
+    if(debug){
+        printf("------------------------------------[lines]-----------------------------------\n");
+        for(u32 i = 0; i < cmp->line_lengths.len; i++){
+            printf("[%u] length: %u\n", i+1, cmp->line_lengths.data[i]);
+        }
+        printf("------------------------------------[tokens]-----------------------------------\n");
+        for(u32 i = 0; i < cmp->tokens.len; i++){
+            Token t = cmp->tokens.data[i];
+            CodePos pos = Compiler_getLineAndColumn(cmp, t.begin);
+            char* tokstr = malloc(4096);
+            strncpy(tokstr, cmp->code + t.begin, t.length);
+            tokstr[t.length] = 0;
+            printf("[l:%3u, c:%3u] %s '%s'\n", 
+                pos.line, pos.column,
+                TokenType_toString(t.type), tokstr);
+            free(tokstr);
+        }
+    }
+    if(!success){
+        fclose(f);
+        return false;
+    }
+
+    success = Compiler_parse(cmp);
+    if(!success){
+        fclose(f);
+        return false;
+    }
+
+    success = compileFile(cmp, f);
+    fclose(f);
+    if(success){
+        cmp->state = CompilerState_Success;
+    }
+    
+    return success;
+}
diff --git a/src/compiler/compiler.c b/src/compiler/Lexer.c
similarity index 100%
rename from src/compiler/compiler.c
rename to src/compiler/Lexer.c
diff --git a/src/main.c b/src/main.c
index 8393dfc..d6c3658 100644
--- a/src/main.c
+++ b/src/main.c
@@ -135,15 +135,16 @@ i32 compileSources(cstr source_file, cstr out_file){
     Compiler cmp;
     Compiler_init(&cmp);
     bool success = Compiler_compile(&cmp, source_file, out_file, true);
-    Compiler_free(&cmp);
     if(!success){
         if(cmp.error_message){
             printfe("COMPILER ERROR: %s\n", cmp.error_message);
             free(cmp.error_message);
         }
         else printfe("COMPILER ERROR: unknown (error_message is null)\n");
+        Compiler_free(&cmp);
         return 111;
     }
-
+    
+    Compiler_free(&cmp);
     return 0;
 }