diff --git a/DTLib/Extensions/StringConverter.cs b/DTLib/Extensions/StringConverter.cs
index a3ce624..80d94b1 100644
--- a/DTLib/Extensions/StringConverter.cs
+++ b/DTLib/Extensions/StringConverter.cs
@@ -44,30 +44,47 @@ public static class StringConverter
     public static bool StartsWith(this string s, char c) => s[0] == c;
     public static bool EndsWith(this string s, char c) => s[s.Length - 1] == c;
 
-    public static string MergeToString(params object[] parts)
+    public static string MergeToString<TVal>(params TVal[] parts)
     {
+        if (parts.Length == 0)
+            return "";
         StringBuilder builder = new();
         for (int i = 0; i < parts.Length; i++)
             builder.Append(parts[i]);
         return builder.ToString();
     }
-    public static string MergeToString<T>(this IEnumerable<T> collection, string separator)
+    public static string MergeToString<TVal, TSep>(TSep separator, params TVal[] parts)
     {
-        StringBuilder builder = new();
-        foreach (T elem in collection)
-        {
-            builder.Append(elem);
-            builder.Append(separator);
-        }
-        if (builder.Length == 0)
+        if (parts.Length == 0)
             return "";
-        builder.Remove(builder.Length - separator.Length, separator.Length);
+        StringBuilder builder = new();
+        builder.Append(parts[0]);
+        for (int i = 1; i < parts.Length; i++)
+        {
+            builder.Append(separator);
+            builder.Append(parts[i]);
+        }
         return builder.ToString();
     }
-    public static string MergeToString<T>(this IEnumerable<T> collection)
+    
+    public static string MergeToString<TVal, TSep>(this IEnumerable<TVal> collection, TSep separator)
     {
         StringBuilder builder = new();
-        foreach (T elem in collection)
+        using var e = collection.GetEnumerator();
+        if(e.MoveNext()) 
+            builder.Append(e.Current);
+        while (e.MoveNext())
+        {
+            builder.Append(separator);
+            builder.Append(e.Current);
+        }
+        return builder.ToString();
+    }
+    
+    public static string MergeToString<TVal>(this IEnumerable<TVal> collection)
+    {
+        StringBuilder builder = new();
+        foreach (var elem in collection)
             builder.Append(elem);
         return builder.ToString();
     }
diff --git a/DTLib/Filesystem/File.cs b/DTLib/Filesystem/File.cs
index 8ed8912..85b58ee 100644
--- a/DTLib/Filesystem/File.cs
+++ b/DTLib/Filesystem/File.cs
@@ -3,7 +3,7 @@ namespace DTLib.Filesystem;
 
 public static class File
 {
-    public static int GetSize(string file) => new System.IO.FileInfo(file).Length.ToInt();
+    public static long GetSize(string file) => new System.IO.FileInfo(file).Length;
 
     public static bool Exists(string file) => System.IO.File.Exists(file);
 
@@ -32,9 +32,10 @@ public static class File
     public static byte[] ReadAllBytes(string file)
     {
         using System.IO.FileStream stream = OpenRead(file);
-        int size = GetSize(file);
+        int size = GetSize(file).ToInt();
         byte[] output = new byte[size];
-        stream.Read(output, 0, size);
+        if (stream.Read(output, 0, size) < size)
+            throw new Exception("can't read all bytes");
         stream.Close();
         return output;
     }
diff --git a/DTLib/Filesystem/New/Directory.cs b/DTLib/Filesystem/New/Directory.cs
new file mode 100644
index 0000000..bb2a280
--- /dev/null
+++ b/DTLib/Filesystem/New/Directory.cs
@@ -0,0 +1,120 @@
+namespace DTLib.Filesystem.New;
+
+public static class Directory
+{
+    public static bool Exists(string dir) => System.IO.Directory.Exists(dir);
+
+    // создает папку, если её не существует
+    public static void Create(string dir)
+    {
+        if (!Exists(dir))
+        {
+            // проверяет существование папки, в которой нужно создать dir
+            if (dir.Contains(Путь.Разд) && !Exists(dir.Remove(dir.LastIndexOf(Путь.Разд))))
+                Create(dir.Remove(dir.LastIndexOf(Путь.Разд)));
+            System.IO.Directory.CreateDirectory(dir);
+        }
+    }
+    // копирует все файлы и папки
+    public static void Copy(string source_dir, string new_dir, bool owerwrite = false)
+    {
+        Create(new_dir);
+        var subdirs = new List<string>();
+        List<string> files = GetAllFiles(source_dir, ref subdirs);
+        for (int i = 0; i < subdirs.Count; i++)
+            Create(subdirs[i].Replace(source_dir, new_dir));
+        for (int i = 0; i < files.Count; i++)
+            File.Copy(files[i], files[i].Replace(source_dir, new_dir), owerwrite);
+    }
+
+    // копирует все файлы и папки и выдаёт список конфликтующих файлов
+    public static void Copy(string source_dir, string new_dir, out List<string> conflicts, bool owerwrite = false)
+    {
+        conflicts = new List<string>();
+        var subdirs = new List<string>();
+        List<string> files = GetAllFiles(source_dir, ref subdirs);
+        Create(new_dir);
+        for (int i = 0; i < subdirs.Count; i++)
+            Create(subdirs[i].Replace(source_dir, new_dir));
+        for (int i = 0; i < files.Count; i++)
+        {
+            string newfile = files[i].Replace(source_dir, new_dir);
+            if (File.Exists(newfile))
+                conflicts.Add(newfile);
+            File.Copy(files[i], newfile, owerwrite);
+        }
+    }
+
+    // удаляет папку со всеми подпапками и файлами
+    public static void Delete(string dir)
+    {
+        var subdirs = new List<string>();
+        List<string> files = GetAllFiles(dir, ref subdirs);
+        for (int i = 0; i < files.Count; i++)
+            File.Delete(files[i]);
+        for (int i = subdirs.Count - 1; i >= 0; i--)
+        {
+            Log($"deleting {subdirs[i]}");
+            if (Exists(subdirs[i]))
+                System.IO.Directory.Delete(subdirs[i], true);
+        }
+        Log($"deleting {dir}");
+        if (Exists(dir))
+            System.IO.Directory.Delete(dir, true);
+    }
+
+    public static string[] GetFiles(string dir) => System.IO.Directory.GetFiles(dir);
+    public static string[] GetFiles(string dir, string searchPattern) => System.IO.Directory.GetFiles(dir, searchPattern);
+    public static string[] GetDirectories(string dir) => System.IO.Directory.GetDirectories(dir);
+
+    // выдает список всех файлов
+    public static List<string> GetAllFiles(string dir)
+    {
+        var all_files = new List<string>();
+        string[] cur_files = GetFiles(dir);
+        for (int i = 0; i < cur_files.Length; i++)
+            all_files.Add(cur_files[i]);
+        string[] cur_subdirs = GetDirectories(dir);
+        for (int i = 0; i < cur_subdirs.Length; i++)
+            all_files.AddRange(GetAllFiles(cur_subdirs[i]));
+        return all_files;
+    }
+
+    // выдает список всех файлов и подпапок в папке
+    public static List<string> GetAllFiles(string dir, ref List<string> all_subdirs)
+    {
+        var all_files = new List<string>();
+        string[] cur_files = GetFiles(dir);
+        for (int i = 0; i < cur_files.Length; i++)
+            all_files.Add(cur_files[i]);
+        string[] cur_subdirs = GetDirectories(dir);
+        for (int i = 0; i < cur_subdirs.Length; i++)
+        {
+            all_subdirs.Add(cur_subdirs[i]);
+            all_files.AddRange(GetAllFiles(cur_subdirs[i], ref all_subdirs));
+        }
+        return all_files;
+    }
+
+    public static string GetCurrent() => System.IO.Directory.GetCurrentDirectory();
+
+    public static void CreateSymlink(string sourceName, string symlinkName)
+    {
+        if (symlinkName.Contains(Путь.Разд))
+            Create(symlinkName.Remove(symlinkName.LastIndexOf(Путь.Разд)));
+        if (!Symlink.CreateSymbolicLink(symlinkName, sourceName, Symlink.SymlinkTarget.Directory))
+            throw new InvalidOperationException($"some error occured while creating symlink\nDirectory.CreateSymlink({symlinkName}, {sourceName})");
+    }
+
+    // copies directory with symlinks instead of files
+    public static int SymCopy(string srcdir, string newdir)
+    {
+        List<string> files = GetAllFiles(srcdir);
+        if (!srcdir.EndsWith(Путь.Разд)) srcdir += Путь.Разд;
+        if (!newdir.EndsWith(Путь.Разд)) newdir += Путь.Разд;
+        int i = 0;
+        for (; i < files.Count; i++)
+            File.CreateSymlink(files[i], files[i].Replace(srcdir, newdir));
+        return i;
+    }
+}
diff --git a/DTLib/Filesystem/New/File.cs b/DTLib/Filesystem/New/File.cs
new file mode 100644
index 0000000..cd8274a
--- /dev/null
+++ b/DTLib/Filesystem/New/File.cs
@@ -0,0 +1,62 @@
+using System.IO;
+
+namespace DTLib.Filesystem.New;
+
+public class File
+{
+    public enum FileOpenMode
+    {
+        // open a file for reading 
+        Read=1, 
+        // (re)create a file for writing
+        Write=2, 
+        // opens file for writing additional data to the end / creates new file 
+        Append=4,
+        // (re)creates file for reading/writing
+        ReadWrite=Read|Write, 
+        // opens file for readng/writing additional data to the end / creates new file 
+        ReadAppend=Read|Append
+    }
+
+    public readonly FileOpenMode Mode;
+    public readonly FileStream Stream;
+    public string Name;
+    
+    public File(string path, FileOpenMode mode)
+    {
+        if(!Exists(path))
+        {
+            if (mode == FileOpenMode.Read)
+                throw new Exception($"file <{path}> is not found");
+        }
+        Mode = mode;
+        Stream = mode switch
+        {
+            FileOpenMode.Read => System.IO.File.Open(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite),
+            FileOpenMode.Write => System.IO.File.Open(path, FileMode.Open, FileAccess.Write, FileShare.ReadWrite),
+            FileOpenMode.Append => System.IO.File.Open(path, FileMode.Append, FileAccess.Write, FileShare.ReadWrite),
+            FileOpenMode.ReadWrite => System.IO.File.Open(path, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite),
+            FileOpenMode.ReadAppend => System.IO.File.Open(path, FileMode.Append, FileAccess.ReadWrite, FileShare.ReadWrite),
+            _ => throw new Exception($"unknown file mode: {mode}")
+        };
+    }
+
+    public static bool Exists(string path) => System.IO.File.Exists(path);
+    
+    public static void Create(string path)
+    {
+        if (Exists(path)) 
+            throw new Exception($"file <{path} already exists");
+        int sepIndex = path.LastIndexOf(Path.Sep);
+        if (sepIndex>-1)
+            Directory.Create(path.Remove(sepIndex));
+        System.IO.File.Create(path).Close();
+    }
+    
+    public static void Delete(string path) => System.IO.File.Delete(path);
+
+    public void Delete(string path)
+    {
+        
+    }
+}
\ No newline at end of file
diff --git a/DTLib/Filesystem/New/Path.cs b/DTLib/Filesystem/New/Path.cs
new file mode 100644
index 0000000..149892d
--- /dev/null
+++ b/DTLib/Filesystem/New/Path.cs
@@ -0,0 +1,39 @@
+using System.Runtime.CompilerServices;
+
+namespace DTLib.Filesystem.New;
+
+public static class Path
+{
+    
+    public static readonly char Sep = Environment.OSVersion.Platform == PlatformID.Win32NT ? '\\' : '/';
+    private static readonly char NotSep = Environment.OSVersion.Platform == PlatformID.Win32NT ? '/' : '\\' ;
+    
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static string Concat(string path, string addition) => $"{path}{Sep}{addition}";
+    
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static string Concat(params string[] parts) => StringConverter.MergeToString(Sep, parts);
+
+    public static string FixSeparators(string path)
+    {
+        var chars = path.ToCharArray();
+        int length = path.Length;
+        for(int i=0; i<length; i++)
+            if (chars[i] == NotSep)
+                chars[i] = Sep;
+        return chars.ToString();
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static string Resolve(params string[] parts) => FixSeparators(Concat(parts));
+    
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static string Resolve(string path, string addition) => FixSeparators(Concat(path, addition));
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static void ThrowIfEscapes(string path)
+    {
+        if (path.Contains(".."))
+            throw new Exception($"path <{path}> uses <..>, that's not allowed");
+    }
+}
\ No newline at end of file