diff --git a/build.bat b/build.bat
index 308ef81..acbf959 100644
--- a/build.bat
+++ b/build.bat
@@ -3,6 +3,6 @@ call ../misc/compile_setup.bat
 
 mkdir build
 cd build
-cl -Fe:bld.exe ../build_tool/build_main.cpp -WX -W3 -wd4200 -diagnostics:column -nologo -Zi -D_CRT_SECURE_NO_WARNINGS
+cl -Fe:bld.exe ../build_tool/build_main.cpp -FC -WX -W3 -wd4200 -diagnostics:column -nologo -Zi -D_CRT_SECURE_NO_WARNINGS
 cd ..
 build\bld.exe
diff --git a/build_file.cpp b/build_file.cpp
index 47ff140..ea645a3 100644
--- a/build_file.cpp
+++ b/build_file.cpp
@@ -8,7 +8,7 @@ int Main() {
     Strs files = ListDir("../tests");
     CompileFiles(cc, {"../tests/main_core_as_header.cpp", "../core_library/core.c"});
     For(files) {
-        if (S8_Find(it, "test_"_s, 0, 0)) {
+        if (S8_Find(it, "test_"_s)) {
             CompileFiles(cc, it);
         }
     }
diff --git a/build_tool/build_lib.cpp b/build_tool/build_lib.cpp
index 918ee49..38fd2e6 100644
--- a/build_tool/build_lib.cpp
+++ b/build_tool/build_lib.cpp
@@ -43,134 +43,11 @@ DEBUG = -fsanitize=address
 #define AND_CL_STRING_TERMINATE_ON_NEW_LINE
 #include "../standalone_libraries/clexer.c"
 
-#define SRC_CACHE_ENTRY_COUNT 1024
-struct SRC_CacheEntry {
-    uint64_t filepath_hash;
-    uint64_t file_hash;
-    uint64_t includes_hash;
-    uint64_t total_hash;
-};
-
-struct SRC_Cache {
-    int entry_cap;
-    int entry_len;
-    SRC_CacheEntry entries[SRC_CACHE_ENTRY_COUNT];
-};
-
-double SRC_Time;
-SRC_Cache *SRC_InMemoryCache;
-SRC_Cache *SRC_FromFileCache;
-CL_ArenaTuple SRC_ArenaTuple;
-S8_String SRC_CacheFilename;
 MA_Arena PernamentArena;
 MA_Arena *Perm = &PernamentArena;
-CL_SearchPaths SRC_SearchPaths = {}; // @todo;
 Table<S8_String> CMDLine;
 
-void SRC_InitCache(MA_Arena *arena, S8_String cachefilename) {
-    SRC_CacheFilename = cachefilename;
-    CL_InitDefaultTuple(&SRC_ArenaTuple);
-
-    SRC_InMemoryCache = MA_PushStruct(arena, SRC_Cache);
-    SRC_InMemoryCache->entry_cap = SRC_CACHE_ENTRY_COUNT;
-
-    SRC_FromFileCache = MA_PushStruct(arena, SRC_Cache);
-    SRC_FromFileCache->entry_cap = SRC_CACHE_ENTRY_COUNT;
-
-    S8_String cache = OS_ReadFile(arena, SRC_CacheFilename);
-    if (cache.len) MA_MemoryCopy(SRC_FromFileCache, cache.str, cache.len);
-}
-
-void SRC_SaveCache() {
-    S8_String dump = S8_Make((char *)SRC_InMemoryCache, sizeof(SRC_Cache));
-    OS_WriteFile(SRC_CacheFilename, dump);
-}
-
-SRC_CacheEntry *SRC_AddHash(uint64_t filepath, uint64_t file, uint64_t includes) {
-    IO_Assert(SRC_InMemoryCache->entry_len + 1 < SRC_InMemoryCache->entry_cap);
-    SRC_CacheEntry *result = SRC_InMemoryCache->entries + SRC_InMemoryCache->entry_len++;
-    result->filepath_hash = filepath;
-    result->file_hash = file;
-    result->includes_hash = includes;
-    result->total_hash = HashBytes(result, sizeof(uint64_t) * 3);
-    return result;
-}
-
-SRC_CacheEntry *SRC_FindCache(SRC_Cache *cache, uint64_t filepath_hash) {
-    for (int cache_i = 0; cache_i < cache->entry_len; cache_i += 1) {
-        SRC_CacheEntry *it = cache->entries + cache_i;
-        if (it->filepath_hash == filepath_hash) {
-            return it;
-        }
-    }
-    return 0;
-}
-
-SRC_CacheEntry *SRC_HashFile(S8_String file, char *parent_file) {
-    char *resolved_file = CL_ResolveFilepath(Perm, &SRC_SearchPaths, file.str, parent_file, false);
-    if (!resolved_file) {
-        IO_Printf("Failed to resolve file: %s\n", file.str);
-        return 0;
-    }
-
-    uint64_t filepath_hash = HashBytes(resolved_file, S8_Length(resolved_file));
-    SRC_CacheEntry *entry = SRC_FindCache(SRC_InMemoryCache, filepath_hash);
-    if (entry) return entry;
-
-    CL_LexResult *first_lex = CL_LexFile(&SRC_ArenaTuple, resolved_file);
-    IO_Assert(first_lex);
-    uint64_t file_hash = HashBytes(first_lex->stream_begin, first_lex->stream - first_lex->stream_begin);
-    uint64_t includes_hash = 13;
-
-    CL_LexList list = CL_MakeLexList(first_lex);
-    for (CL_IncludeIter iter = CL_IterateIncludes(&list); iter.filename; CL_GetNextInclude(&iter)) {
-        if (iter.is_system_include) continue;
-
-        S8_String file_it = S8_MakeFromChar(iter.filename);
-        SRC_CacheEntry *cache = SRC_HashFile(file_it, resolved_file);
-        if (!cache) {
-            IO_Printf("Missing cache for: %s\n", file_it.str);
-            continue;
-        }
-
-        includes_hash = HashMix(includes_hash, cache->total_hash);
-    }
-
-    SRC_CacheEntry *result = SRC_AddHash(filepath_hash, file_hash, includes_hash);
-    return result;
-}
-
-bool SRC_WasModified(S8_String file, S8_String artifact_path) {
-    double time_start = OS_GetTime();
-
-    if (OS_FileExists(file) == false) {
-        IO_Printf("FAILED File doesnt exist: %.*s\n", S8_Expand(file));
-        exit(0);
-    }
-    if (OS_IsAbsolute(file) == false) {
-        file = OS_GetAbsolutePath(Perm, file);
-    }
-
-    S8_String without_ext = S8_ChopLastPeriod(file);
-    S8_String name_only = S8_SkipToLastSlash(without_ext);
-
-    if (artifact_path.len == 0) artifact_path = S8_Format(Perm, "%.*s.%s", S8_Expand(name_only), IF_WINDOWS_ELSE("obj", "o"));
-    bool modified = OS_FileExists(artifact_path) == false;
-
-    SRC_CacheEntry *in_memory = SRC_HashFile(file, 0);
-    IO_Assert(in_memory);
-
-    if (modified == false) {
-        SRC_CacheEntry *from_file = SRC_FindCache(SRC_FromFileCache, in_memory->filepath_hash);
-        if (from_file == 0 || (in_memory->total_hash != from_file->total_hash)) {
-            modified = true;
-        }
-    }
-
-    SRC_Time = SRC_Time + (OS_GetTime() - time_start);
-
-    return modified;
-}
+#include "cache.c"
 
 //
 //
diff --git a/build_tool/build_main.cpp b/build_tool/build_main.cpp
index 1403519..a709944 100644
--- a/build_tool/build_main.cpp
+++ b/build_tool/build_main.cpp
@@ -28,7 +28,7 @@ int main(int argument_count, char **arguments) {
     {
         S8_List files_current_dir = OS_ListDir(Perm, S8_Lit(".."), 0);
         for (S8_Node *it = files_current_dir.first; it; it = it->next) {
-            if (S8_Find(it->string, S8_Lit("build_file.c"), S8_IGNORE_CASE, 0)) {
+            if (S8_Find(it->string, S8_Lit("build_file.c"), S8_IgnoreCase)) {
                 build_file = it->string;
             }
         }
diff --git a/build_tool/cache.c b/build_tool/cache.c
new file mode 100644
index 0000000..bf1ad75
--- /dev/null
+++ b/build_tool/cache.c
@@ -0,0 +1,126 @@
+
+#define SRC_CACHE_ENTRY_COUNT 1024
+struct SRC_CacheEntry {
+    uint64_t filepath_hash;
+    uint64_t file_hash;
+    uint64_t includes_hash;
+    uint64_t total_hash;
+};
+
+struct SRC_Cache {
+    int entry_cap;
+    int entry_len;
+    SRC_CacheEntry entries[SRC_CACHE_ENTRY_COUNT];
+};
+
+double SRC_Time;
+SRC_Cache *SRC_InMemoryCache;
+SRC_Cache *SRC_FromFileCache;
+CL_ArenaTuple SRC_ArenaTuple;
+S8_String SRC_CacheFilename;
+CL_SearchPaths SRC_SearchPaths = {}; // @todo;
+
+void SRC_InitCache(MA_Arena *arena, S8_String cachefilename) {
+    SRC_CacheFilename = cachefilename;
+    CL_InitDefaultTuple(&SRC_ArenaTuple);
+
+    SRC_InMemoryCache = MA_PushStruct(arena, SRC_Cache);
+    SRC_InMemoryCache->entry_cap = SRC_CACHE_ENTRY_COUNT;
+
+    SRC_FromFileCache = MA_PushStruct(arena, SRC_Cache);
+    SRC_FromFileCache->entry_cap = SRC_CACHE_ENTRY_COUNT;
+
+    S8_String cache = OS_ReadFile(arena, SRC_CacheFilename);
+    if (cache.len) MA_MemoryCopy(SRC_FromFileCache, cache.str, cache.len);
+}
+
+void SRC_SaveCache() {
+    S8_String dump = S8_Make((char *)SRC_InMemoryCache, sizeof(SRC_Cache));
+    OS_WriteFile(SRC_CacheFilename, dump);
+}
+
+SRC_CacheEntry *SRC_AddHash(uint64_t filepath, uint64_t file, uint64_t includes) {
+    IO_Assert(SRC_InMemoryCache->entry_len + 1 < SRC_InMemoryCache->entry_cap);
+    SRC_CacheEntry *result = SRC_InMemoryCache->entries + SRC_InMemoryCache->entry_len++;
+    result->filepath_hash = filepath;
+    result->file_hash = file;
+    result->includes_hash = includes;
+    result->total_hash = HashBytes(result, sizeof(uint64_t) * 3);
+    return result;
+}
+
+SRC_CacheEntry *SRC_FindCache(SRC_Cache *cache, uint64_t filepath_hash) {
+    for (int cache_i = 0; cache_i < cache->entry_len; cache_i += 1) {
+        SRC_CacheEntry *it = cache->entries + cache_i;
+        if (it->filepath_hash == filepath_hash) {
+            return it;
+        }
+    }
+    return 0;
+}
+
+SRC_CacheEntry *SRC_HashFile(S8_String file, char *parent_file) {
+    char *resolved_file = CL_ResolveFilepath(Perm, &SRC_SearchPaths, file.str, parent_file, false);
+    if (!resolved_file) {
+        IO_Printf("Failed to resolve file: %s\n", file.str);
+        return 0;
+    }
+
+    uint64_t filepath_hash = HashBytes(resolved_file, S8_Length(resolved_file));
+    SRC_CacheEntry *entry = SRC_FindCache(SRC_InMemoryCache, filepath_hash);
+    if (entry) return entry;
+
+    CL_LexResult *first_lex = CL_LexFile(&SRC_ArenaTuple, resolved_file);
+    IO_Assert(first_lex);
+    uint64_t file_hash = HashBytes(first_lex->stream_begin, first_lex->stream - first_lex->stream_begin);
+    uint64_t includes_hash = 13;
+
+    CL_LexList list = CL_MakeLexList(first_lex);
+    for (CL_IncludeIter iter = CL_IterateIncludes(&list); iter.filename; CL_GetNextInclude(&iter)) {
+        if (iter.is_system_include) continue;
+
+        S8_String file_it = S8_MakeFromChar(iter.filename);
+        SRC_CacheEntry *cache = SRC_HashFile(file_it, resolved_file);
+        if (!cache) {
+            IO_Printf("Missing cache for: %s\n", file_it.str);
+            continue;
+        }
+
+        includes_hash = HashMix(includes_hash, cache->total_hash);
+    }
+
+    SRC_CacheEntry *result = SRC_AddHash(filepath_hash, file_hash, includes_hash);
+    return result;
+}
+
+bool SRC_WasModified(S8_String file, S8_String artifact_path) {
+    double time_start = OS_GetTime();
+
+    if (OS_FileExists(file) == false) {
+        IO_Printf("FAILED File doesnt exist: %.*s\n", S8_Expand(file));
+        exit(0);
+    }
+    if (OS_IsAbsolute(file) == false) {
+        file = OS_GetAbsolutePath(Perm, file);
+    }
+
+    S8_String without_ext = S8_ChopLastPeriod(file);
+    S8_String name_only = S8_SkipToLastSlash(without_ext);
+
+    if (artifact_path.len == 0) artifact_path = S8_Format(Perm, "%.*s.%s", S8_Expand(name_only), IF_WINDOWS_ELSE("obj", "o"));
+    bool modified = OS_FileExists(artifact_path) == false;
+
+    SRC_CacheEntry *in_memory = SRC_HashFile(file, 0);
+    IO_Assert(in_memory);
+
+    if (modified == false) {
+        SRC_CacheEntry *from_file = SRC_FindCache(SRC_FromFileCache, in_memory->filepath_hash);
+        if (from_file == 0 || (in_memory->total_hash != from_file->total_hash)) {
+            modified = true;
+        }
+    }
+
+    SRC_Time = SRC_Time + (OS_GetTime() - time_start);
+
+    return modified;
+}
\ No newline at end of file
diff --git a/core_library/core.c b/core_library/core.c
index a3629b4..16fcf68 100644
--- a/core_library/core.c
+++ b/core_library/core.c
@@ -1,5 +1,19 @@
-#include "core.h"
+/*
+@todo
+- Rewrite OS_ListDir, no weird flags and conventions, [relative, absolute, is_dir]
+- add c++ default args using macros
+- Rework string flags
+- String should use allocator instead of arena?
+- Maybe remove completely null termination from S8_String, I think it might complicate and is error prone because one can sometimes assume it's null terminated and it isn't
+- Maybe create a nice C++ binding for strings,
+    - also add String Arrays and String Builder, temp allocators hook ins for nicer api
+    - Iterating over unicode codepoints using For
+- Redesign clexer because the Arena Tuple is hella weird
+    - Maybe remove token array stuff, do standard stream thing, then you need one arena ...
+        - Add filter stuff so we can get includes / comments / normal tokens etc.
+*/
 
+#include "core.h"
 #define STB_SPRINTF_IMPLEMENTATION
 #include "../standalone_libraries/stb_sprintf.h"
 #define IO_VSNPRINTF stbsp_vsnprintf
@@ -20,3 +34,7 @@
 #include "../standalone_libraries/hash.c"
 #include "../standalone_libraries/load_library.c"
 #include "filesystem.c"
+
+// #if LANG_CPP
+//     #include "string.cpp"
+// #endif
\ No newline at end of file
diff --git a/core_library/core.h b/core_library/core.h
index 343ec26..a50bb14 100644
--- a/core_library/core.h
+++ b/core_library/core.h
@@ -12,7 +12,7 @@
 #include "../standalone_libraries/load_library.h"
 #include "filesystem.h"
 
-#ifdef __cplusplus
+#if LANG_CPP
     #include "../standalone_libraries/defer.hpp"
     #define TABLE_ASSERT IO_Assert
     #define TABLE_Allocator M_Allocator
@@ -28,4 +28,5 @@
     #define ARRAY_SET_DEFAULT_ALLOCATOR \
         if (!allocator.p) allocator = M_GetSystemAllocator();
     #include "../standalone_libraries/array.hpp"
+// #include "string.hpp"
 #endif
diff --git a/core_library/filesystem.c b/core_library/filesystem.c
index 24f5c76..6c17798 100644
--- a/core_library/filesystem.c
+++ b/core_library/filesystem.c
@@ -1,7 +1,3 @@
-#include "filesystem.h"
-
-#define OS_LENGTHOF(x) ((int64_t)((sizeof(x) / sizeof((x)[0]))))
-
 #ifdef _WIN32
     #ifndef NOMINMAX
         #define NOMINMAX
@@ -47,7 +43,7 @@ OS_API bool OS_IsAbsolute(S8_String path) {
 
 OS_API S8_String OS_GetExePath(MA_Arena *arena) {
     wchar_t wbuffer[1024];
-    DWORD wsize = GetModuleFileNameW(0, wbuffer, OS_LENGTHOF(wbuffer));
+    DWORD wsize = GetModuleFileNameW(0, wbuffer, MA_LENGTHOF(wbuffer));
     IO_Assert(wsize != 0);
 
     S8_String path = UTF_CreateStringFromWidechar(arena, wbuffer, wsize);
@@ -64,7 +60,7 @@ OS_API S8_String OS_GetExeDir(MA_Arena *arena) {
 
 OS_API S8_String OS_GetWorkingDir(MA_Arena *arena) {
     wchar_t wbuffer[1024];
-    DWORD wsize = GetCurrentDirectoryW(OS_LENGTHOF(wbuffer), wbuffer);
+    DWORD wsize = GetCurrentDirectoryW(MA_LENGTHOF(wbuffer), wbuffer);
     IO_Assert(wsize != 0);
     IO_Assert(wsize < 1022);
     wbuffer[wsize++] = '/';
@@ -77,15 +73,15 @@ OS_API S8_String OS_GetWorkingDir(MA_Arena *arena) {
 
 OS_API void OS_SetWorkingDir(S8_String path) {
     wchar_t wpath[1024];
-    UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), path.str, path.len);
+    UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), path.str, path.len);
     SetCurrentDirectoryW(wpath);
 }
 
 OS_API S8_String OS_GetAbsolutePath(MA_Arena *arena, S8_String relative) {
     wchar_t wpath[1024];
-    UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), relative.str, relative.len);
+    UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), relative.str, relative.len);
     wchar_t wpath_abs[1024];
-    DWORD written = GetFullPathNameW((wchar_t *)wpath, OS_LENGTHOF(wpath_abs), wpath_abs, 0);
+    DWORD written = GetFullPathNameW((wchar_t *)wpath, MA_LENGTHOF(wpath_abs), wpath_abs, 0);
     if (written == 0)
         return S8_MakeEmpty();
     S8_String path = UTF_CreateStringFromWidechar(arena, wpath_abs, written);
@@ -95,7 +91,7 @@ OS_API S8_String OS_GetAbsolutePath(MA_Arena *arena, S8_String relative) {
 
 OS_API bool OS_FileExists(S8_String path) {
     wchar_t wbuff[1024];
-    UTF_CreateWidecharFromChar(wbuff, OS_LENGTHOF(wbuff), path.str, path.len);
+    UTF_CreateWidecharFromChar(wbuff, MA_LENGTHOF(wbuff), path.str, path.len);
     DWORD attribs = GetFileAttributesW(wbuff);
     bool result = attribs == INVALID_FILE_ATTRIBUTES ? false : true;
     return result;
@@ -103,14 +99,14 @@ OS_API bool OS_FileExists(S8_String path) {
 
 OS_API bool OS_IsDir(S8_String path) {
     wchar_t wbuff[1024];
-    UTF_CreateWidecharFromChar(wbuff, OS_LENGTHOF(wbuff), path.str, path.len);
+    UTF_CreateWidecharFromChar(wbuff, MA_LENGTHOF(wbuff), path.str, path.len);
     DWORD dwAttrib = GetFileAttributesW(wbuff);
     return dwAttrib != INVALID_FILE_ATTRIBUTES && (dwAttrib & FILE_ATTRIBUTE_DIRECTORY);
 }
 
 OS_API bool OS_IsFile(S8_String path) {
     wchar_t wbuff[1024];
-    UTF_CreateWidecharFromChar(wbuff, OS_LENGTHOF(wbuff), path.str, path.len);
+    UTF_CreateWidecharFromChar(wbuff, MA_LENGTHOF(wbuff), path.str, path.len);
     DWORD dwAttrib = GetFileAttributesW(wbuff);
     bool is_file = (dwAttrib & FILE_ATTRIBUTE_DIRECTORY) == 0;
     return dwAttrib != INVALID_FILE_ATTRIBUTES && is_file;
@@ -143,8 +139,8 @@ OS_API S8_List OS_ListDir(MA_Arena *arena, S8_String path, unsigned flags) {
     for (S8_Node *it = dirs_to_read.first; it; it = it->next) {
         wchar_t wbuff[1024];
         S8_String modified_path = S8_Format(scratch.arena, "%.*s\\*", (int)it->string.len, it->string.str);
-        IO_Assert(modified_path.len < OS_LENGTHOF(wbuff));
-        int64_t wsize = UTF_CreateWidecharFromChar(wbuff, OS_LENGTHOF(wbuff), modified_path.str, modified_path.len);
+        IO_Assert(modified_path.len < MA_LENGTHOF(wbuff));
+        int64_t wsize = UTF_CreateWidecharFromChar(wbuff, MA_LENGTHOF(wbuff), modified_path.str, modified_path.len);
         IO_Assert(wsize);
 
         WIN32_FIND_DATAW ffd;
@@ -197,7 +193,7 @@ OS_API S8_List OS_ListDir(MA_Arena *arena, S8_String path, unsigned flags) {
 
 OS_API OS_Result OS_MakeDir(S8_String path) {
     wchar_t wpath[1024];
-    UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), path.str, path.len);
+    UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), path.str, path.len);
     BOOL success = CreateDirectoryW(wpath, NULL);
     OS_Result result = OS_SUCCESS;
     if (success == 0) {
@@ -217,10 +213,10 @@ OS_API OS_Result OS_MakeDir(S8_String path) {
 
 OS_API OS_Result OS_CopyFile(S8_String from, S8_String to, bool overwrite) {
     wchar_t wfrom[1024];
-    UTF_CreateWidecharFromChar(wfrom, OS_LENGTHOF(wfrom), from.str, from.len);
+    UTF_CreateWidecharFromChar(wfrom, MA_LENGTHOF(wfrom), from.str, from.len);
 
     wchar_t wto[1024];
-    UTF_CreateWidecharFromChar(wto, OS_LENGTHOF(wto), to.str, to.len);
+    UTF_CreateWidecharFromChar(wto, MA_LENGTHOF(wto), to.str, to.len);
 
     BOOL fail_if_exists = !overwrite;
     BOOL success = CopyFileW(wfrom, wto, fail_if_exists);
@@ -233,7 +229,7 @@ OS_API OS_Result OS_CopyFile(S8_String from, S8_String to, bool overwrite) {
 
 OS_API OS_Result OS_DeleteFile(S8_String path) {
     wchar_t wpath[1024];
-    UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), path.str, path.len);
+    UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), path.str, path.len);
     BOOL success = DeleteFileW(wpath);
     OS_Result result = OS_SUCCESS;
     if (success == 0)
@@ -247,7 +243,7 @@ OS_API OS_Result OS_DeleteDir(S8_String path, unsigned flags) {
         S8_List list = OS_ListDir(scratch.arena, path, OS_RECURSIVE);
         S8_Node *dirs_to_remove = 0;
         for (S8_Node *it = list.first; it; it = it->next) {
-            if (!S8_EndsWith(it->string, S8_Lit("/"), S8_IGNORE_CASE)) {
+            if (!S8_EndsWith(it->string, S8_Lit("/"), S8_IgnoreCase)) {
                 OS_DeleteFile(it->string);
             }
             else {
@@ -264,7 +260,7 @@ OS_API OS_Result OS_DeleteDir(S8_String path, unsigned flags) {
     }
     else {
         wchar_t wpath[1024];
-        UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), path.str, path.len);
+        UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), path.str, path.len);
         BOOL success = RemoveDirectoryW(wpath);
         OS_Result result = OS_SUCCESS;
         if (success == 0)
@@ -275,7 +271,7 @@ OS_API OS_Result OS_DeleteDir(S8_String path, unsigned flags) {
 
 static OS_Result OS__WriteFile(S8_String path, S8_String data, bool append) {
     wchar_t wpath[1024];
-    UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), path.str, path.len);
+    UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), path.str, path.len);
     OS_Result result = OS_FAILURE;
 
     DWORD access = GENERIC_WRITE;
@@ -316,7 +312,7 @@ OS_API S8_String OS_ReadFile(MA_Arena *arena, S8_String path) {
     MA_Checkpoint checkpoint = MA_Save(arena);
 
     wchar_t wpath[1024];
-    UTF_CreateWidecharFromChar(wpath, OS_LENGTHOF(wpath), path.str, path.len);
+    UTF_CreateWidecharFromChar(wpath, MA_LENGTHOF(wpath), path.str, path.len);
     HANDLE handle = CreateFileW(wpath, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
     if (handle != INVALID_HANDLE_VALUE) {
         LARGE_INTEGER file_size;
@@ -680,7 +676,7 @@ OS_API S8_List S8_SplitOnRegex(MA_Arena *arena, S8_String string, S8_String rege
         S8_String before_match = S8_Make(string.str, match.pos);
         S8_String the_match = S8_Make(string.str + match.pos, match.size);
         if (before_match.len) S8_AddNode(arena, &result, before_match);
-        if (flags & S8_SPLIT_INCLUSIVE) {
+        if (flags & S8_SplitFlag_SplitInclusive) {
             if (the_match.len) S8_AddNode(arena, &result, the_match);
         }
         string = S8_Skip(string, match.pos + match.size);
diff --git a/core_library/filesystem.h b/core_library/filesystem.h
index 08aa283..f0ab35b 100644
--- a/core_library/filesystem.h
+++ b/core_library/filesystem.h
@@ -1,4 +1,3 @@
-#pragma once
 // Quick and dirty filesystem operations
 
 #ifndef OS_API
diff --git a/standalone_libraries/string.c b/standalone_libraries/string.c
index fa921f4..ae1138f 100644
--- a/standalone_libraries/string.c
+++ b/standalone_libraries/string.c
@@ -74,7 +74,7 @@ S8_API bool S8_AreEqual(S8_String a, S8_String b, unsigned ignore_case) {
     for (int64_t i = 0; i < a.len; i++) {
         char A = a.str[i];
         char B = b.str[i];
-        if (ignore_case & S8_IGNORE_CASE) {
+        if (ignore_case) {
             A = CHAR_ToLowerCase(A);
             B = CHAR_ToLowerCase(B);
         }
@@ -169,6 +169,10 @@ S8_API S8_String S8_GetPrefix(S8_String string, int64_t len) {
     return result;
 }
 
+S8_API S8_String S8_GetNameNoExtension(S8_String s) {
+    return S8_SkipToLastSlash(S8_ChopLastPeriod(s));
+}
+
 S8_API S8_String S8_Slice(S8_String string, int64_t first_index, int64_t one_past_last_index) {
     if (one_past_last_index < 0) one_past_last_index = string.len + one_past_last_index + 1;
     if (first_index < 0) first_index = string.len + first_index;
@@ -245,13 +249,14 @@ S8_API S8_String S8_ToUpperCase(S8_Allocator allocator, S8_String s) {
     return copy;
 }
 
-S8_API bool S8_Find(S8_String string, S8_String find, unsigned flags, int64_t *index_out) {
+S8_API bool S8_Find(S8_String string, S8_String find, S8_FindFlag flags, int64_t *index_out) {
+    bool ignore_case = flags & S8_FindFlag_IgnoreCase ? true : false;
     bool result = false;
-    if (flags & S8_MATCH_FIND_LAST) {
+    if (flags & S8_FindFlag_MatchFindLast) {
         for (int64_t i = string.len; i != 0; i--) {
             int64_t index = i - 1;
             S8_String substring = S8_Slice(string, index, index + find.len);
-            if (S8_AreEqual(substring, find, flags)) {
+            if (S8_AreEqual(substring, find, ignore_case)) {
                 if (index_out)
                     *index_out = index;
                 result = true;
@@ -262,7 +267,7 @@ S8_API bool S8_Find(S8_String string, S8_String find, unsigned flags, int64_t *i
     else {
         for (int64_t i = 0; i < string.len; i++) {
             S8_String substring = S8_Slice(string, i, i + find.len);
-            if (S8_AreEqual(substring, find, flags)) {
+            if (S8_AreEqual(substring, find, ignore_case)) {
                 if (index_out)
                     *index_out = i;
                 result = true;
@@ -274,14 +279,15 @@ S8_API bool S8_Find(S8_String string, S8_String find, unsigned flags, int64_t *i
     return result;
 }
 
-S8_API S8_List S8_Split(S8_Allocator allocator, S8_String string, S8_String find, unsigned flags) {
-    S8_ASSERT((flags & S8_MATCH_FIND_LAST) == 0);
+S8_API S8_List S8_Split(S8_Allocator allocator, S8_String string, S8_String find, S8_SplitFlag flags) {
     S8_List result = S8_MakeEmptyList();
     int64_t index = 0;
-    while (S8_Find(string, find, flags, &index)) {
+
+    S8_FindFlag find_flag = flags & S8_SplitFlag_IgnoreCase ? S8_FindFlag_IgnoreCase : S8_FindFlag_None;
+    while (S8_Find(string, find, find_flag, &index)) {
         S8_String before_match = S8_Make(string.str, index);
         S8_AddNode(allocator, &result, before_match);
-        if (flags & S8_SPLIT_INCLUSIVE) {
+        if (flags & S8_SplitFlag_SplitInclusive) {
             S8_String match = S8_Make(string.str + index, find.len);
             S8_AddNode(allocator, &result, match);
         }
@@ -294,7 +300,7 @@ S8_API S8_List S8_Split(S8_Allocator allocator, S8_String string, S8_String find
 S8_API S8_String S8_MergeWithSeparator(S8_Allocator allocator, S8_List list, S8_String separator) {
     if (list.node_count == 0) return S8_MakeEmpty();
     if (list.char_count == 0) return S8_MakeEmpty();
-    // S8_ASSERT((flags & S8_MATCH_FIND_LAST) == 0);
+
     int64_t base_size = (list.char_count + 1);
     int64_t sep_size = (list.node_count - 1) * separator.len;
     int64_t size = base_size + sep_size;
@@ -318,11 +324,11 @@ S8_API S8_String S8_Merge(S8_Allocator allocator, S8_List list) {
     return S8_MergeWithSeparator(allocator, list, S8_Lit(""));
 }
 
-S8_API S8_String S8_ReplaceAll(S8_Allocator allocator, S8_String string, S8_String replace, S8_String with, unsigned flags) {
-    S8_ASSERT((flags & S8_MATCH_FIND_LAST) == 0);
-    S8_List list = S8_Split(allocator, string, replace, flags | S8_SPLIT_INCLUSIVE);
+S8_API S8_String S8_ReplaceAll(S8_Allocator allocator, S8_String string, S8_String replace, S8_String with, bool ignore_case) {
+    S8_SplitFlag split_flag = ignore_case ? S8_SplitFlag_IgnoreCase : S8_SplitFlag_None;
+    S8_List list = S8_Split(allocator, string, replace, split_flag | S8_SplitFlag_SplitInclusive);
     for (S8_Node *it = list.first; it; it = it->next) {
-        if (S8_AreEqual(it->string, replace, flags)) {
+        if (S8_AreEqual(it->string, replace, ignore_case)) {
             S8_ReplaceNodeString(&list, it, with);
         }
     }
@@ -330,11 +336,12 @@ S8_API S8_String S8_ReplaceAll(S8_Allocator allocator, S8_String string, S8_Stri
     return result;
 }
 
-S8_API S8_List S8_FindAll(S8_Allocator allocator, S8_String string, S8_String find, unsigned flags) { // @untested
-    S8_ASSERT((flags & S8_MATCH_FIND_LAST) == 0);
+S8_API S8_List S8_FindAll(S8_Allocator allocator, S8_String string, S8_String find, bool ignore_case) { // @untested
     S8_List result = S8_MakeEmptyList();
     int64_t index = 0;
-    while (S8_Find(string, find, flags, &index)) {
+
+    S8_FindFlag find_flag = ignore_case ? S8_FindFlag_IgnoreCase : 0;
+    while (S8_Find(string, find, find_flag, &index)) {
         S8_String match = S8_Make(string.str + index, find.len);
         S8_AddNode(allocator, &result, match);
         string = S8_Skip(string, index + find.len);
@@ -344,20 +351,20 @@ S8_API S8_List S8_FindAll(S8_Allocator allocator, S8_String string, S8_String fi
 
 S8_API S8_String S8_ChopLastSlash(S8_String s) {
     S8_String result = s;
-    S8_Find(s, S8_Lit("/"), S8_MATCH_FIND_LAST, &result.len);
+    S8_Find(s, S8_Lit("/"), S8_FindFlag_MatchFindLast, &result.len);
     return result;
 }
 
 S8_API S8_String S8_ChopLastPeriod(S8_String s) {
     S8_String result = s;
-    S8_Find(s, S8_Lit("."), S8_MATCH_FIND_LAST, &result.len);
+    S8_Find(s, S8_Lit("."), S8_FindFlag_MatchFindLast, &result.len);
     return result;
 }
 
 S8_API S8_String S8_SkipToLastSlash(S8_String s) {
     int64_t pos;
     S8_String result = s;
-    if (S8_Find(s, S8_Lit("/"), S8_MATCH_FIND_LAST, &pos)) {
+    if (S8_Find(s, S8_Lit("/"), S8_FindFlag_MatchFindLast, &pos)) {
         result = S8_Skip(result, pos + 1);
     }
     return result;
@@ -366,7 +373,7 @@ S8_API S8_String S8_SkipToLastSlash(S8_String s) {
 S8_API S8_String S8_SkipToLastPeriod(S8_String s) {
     int64_t pos;
     S8_String result = s;
-    if (S8_Find(s, S8_Lit("."), S8_MATCH_FIND_LAST, &pos)) {
+    if (S8_Find(s, S8_Lit("."), S8_FindFlag_MatchFindLast, &pos)) {
         result = S8_Skip(result, pos + 1);
     }
     return result;
diff --git a/standalone_libraries/string.h b/standalone_libraries/string.h
index 375bdc2..0e811b4 100644
--- a/standalone_libraries/string.h
+++ b/standalone_libraries/string.h
@@ -11,6 +11,12 @@
     #endif
 #endif
 
+#ifdef __cplusplus
+    #define S8_IF_CPP(x) x
+#else
+    #define S8_IF_CPP(x)
+#endif
+
 #ifndef S8_Allocator
 struct MA_Arena;
     #define S8_Allocator MA_Arena *
@@ -19,12 +25,26 @@ struct MA_Arena;
 typedef struct S8_String S8_String;
 typedef struct S8_Node S8_Node;
 typedef struct S8_List S8_List;
+S8_API int64_t S8_Length(char *string);
 
 struct S8_String {
     char *str;
     int64_t len;
 };
 
+// #ifdef __cplusplus
+// struct String : S8_String {
+//     String() = default;
+//     String(char *s) : S8_String{s, S8_Length(s)} {}
+//     String(char *s, int64_t l) : S8_String{s, l} {}
+//     String(const char *s) : S8_String{(char *)s, S8_Length((char *)s)} {}
+//     String(const char *s, int64_t l) : S8_String{(char *)s, l} {}
+//     String(S8_String s) : S8_String{s.str, s.len} {}
+
+//     // @todo add unicode iterator
+// };
+// #endif
+
 struct S8_Node {
     S8_Node *next;
     S8_String string;
@@ -37,11 +57,20 @@ struct S8_List {
     S8_Node *last;
 };
 
+const int S8_IgnoreCase = true;
+
+typedef int S8_FindFlag;
 enum {
-    S8_NO_FLAGS = 0,
-    S8_IGNORE_CASE = 1,
-    S8_SPLIT_INCLUSIVE = 4,
-    S8_MATCH_FIND_LAST = 32,
+    S8_FindFlag_None = 0,
+    S8_FindFlag_IgnoreCase = 1,
+    S8_FindFlag_MatchFindLast = 2,
+};
+
+typedef int S8_SplitFlag;
+enum {
+    S8_SplitFlag_None = 0,
+    S8_SplitFlag_IgnoreCase = 1,
+    S8_SplitFlag_SplitInclusive = 2,
 };
 
 #if defined(__has_attribute)
@@ -80,9 +109,9 @@ S8_API bool CHAR_IsAlphabetic(char a);
 S8_API bool CHAR_IsIdent(char a);
 S8_API bool CHAR_IsDigit(char a);
 S8_API bool CHAR_IsAlphanumeric(char a);
-S8_API bool S8_AreEqual(S8_String a, S8_String b, unsigned ignore_case);
-S8_API bool S8_EndsWith(S8_String a, S8_String end, unsigned ignore_case);
-S8_API bool S8_StartsWith(S8_String a, S8_String start, unsigned ignore_case);
+S8_API bool S8_AreEqual(S8_String a, S8_String b, unsigned ignore_case S8_IF_CPP(= false));
+S8_API bool S8_EndsWith(S8_String a, S8_String end, unsigned ignore_case S8_IF_CPP(= false));
+S8_API bool S8_StartsWith(S8_String a, S8_String start, unsigned ignore_case S8_IF_CPP(= false));
 S8_API S8_String S8_Make(char *str, int64_t len);
 S8_API S8_String S8_Copy(S8_Allocator allocator, S8_String string);
 S8_API void S8_NormalizePath(S8_String s);
@@ -95,26 +124,28 @@ S8_API S8_String S8_Trim(S8_String string);
 S8_API S8_String S8_TrimEnd(S8_String string);
 S8_API S8_String S8_ToLowerCase(S8_Allocator allocator, S8_String s);
 S8_API S8_String S8_ToUpperCase(S8_Allocator allocator, S8_String s);
-S8_API bool S8_Find(S8_String string, S8_String find, unsigned flags, int64_t *index_out);
-S8_API S8_List S8_Split(S8_Allocator allocator, S8_String string, S8_String find, unsigned flags);
-S8_API S8_String S8_MergeWithSeparator(S8_Allocator allocator, S8_List list, S8_String separator);
-S8_API S8_String S8_Merge(S8_Allocator allocator, S8_List list);
-S8_API S8_String S8_ReplaceAll(S8_Allocator allocator, S8_String string, S8_String replace, S8_String with, unsigned flags);
-S8_API S8_List S8_FindAll(S8_Allocator allocator, S8_String string, S8_String find, unsigned flags);
+S8_API bool S8_Find(S8_String string, S8_String find, S8_FindFlag flags S8_IF_CPP(= S8_FindFlag_None), int64_t *index_out S8_IF_CPP(= 0));
 S8_API S8_String S8_ChopLastSlash(S8_String s);
 S8_API S8_String S8_ChopLastPeriod(S8_String s);
 S8_API S8_String S8_SkipToLastSlash(S8_String s);
 S8_API S8_String S8_SkipToLastPeriod(S8_String s);
+S8_API S8_String S8_GetNameNoExt(S8_String s);
 S8_API bool S8_IsPointerInside(S8_String string, char *p);
 S8_API S8_String S8_SkipToP(S8_String string, char *p);
 S8_API S8_String S8_SkipPast(S8_String string, S8_String a);
-S8_API int64_t S8_Length(char *string);
 S8_API int64_t S8_WideLength(wchar_t *string);
 S8_API S8_String S8_MakeFromChar(char *string);
 S8_API S8_String S8_MakeEmpty(void);
 S8_API S8_List S8_MakeEmptyList(void);
 S8_API S8_String S8_FormatV(S8_Allocator allocator, const char *str, va_list args1);
 S8_API S8_String S8_Format(S8_Allocator allocator, const char *str, ...) S8__PrintfFormat(2, 3);
+
+S8_API S8_List S8_Split(S8_Allocator allocator, S8_String string, S8_String find, S8_SplitFlag flags S8_IF_CPP(= S8_SplitFlag_None));
+S8_API S8_String S8_MergeWithSeparator(S8_Allocator allocator, S8_List list, S8_String separator S8_IF_CPP(= " "_s));
+S8_API S8_String S8_Merge(S8_Allocator allocator, S8_List list);
+S8_API S8_String S8_ReplaceAll(S8_Allocator allocator, S8_String string, S8_String replace, S8_String with, bool ignore_case S8_IF_CPP(= false));
+S8_API S8_List S8_FindAll(S8_Allocator allocator, S8_String string, S8_String find, bool ignore_case S8_IF_CPP(= false));
+
 S8_API S8_Node *S8_CreateNode(S8_Allocator allocator, S8_String string);
 S8_API void S8_ReplaceNodeString(S8_List *list, S8_Node *node, S8_String new_string);
 S8_API void S8_AddExistingNode(S8_List *list, S8_Node *node);
diff --git a/tests/1test_string.cpp b/tests/1test_string.cpp
new file mode 100644
index 0000000..7330dd2
--- /dev/null
+++ b/tests/1test_string.cpp
@@ -0,0 +1,4 @@
+#include "../core_library/core.c"
+
+int main() {
+}
\ No newline at end of file