diff --git a/src/me/topchetoeu/jscript/Main.java b/src/me/topchetoeu/jscript/Main.java
index 6082226..818b328 100644
--- a/src/me/topchetoeu/jscript/Main.java
+++ b/src/me/topchetoeu/jscript/Main.java
@@ -16,6 +16,10 @@ import me.topchetoeu.jscript.events.Observer;
 import me.topchetoeu.jscript.exceptions.EngineException;
 import me.topchetoeu.jscript.exceptions.InterruptException;
 import me.topchetoeu.jscript.exceptions.SyntaxException;
+import me.topchetoeu.jscript.filesystem.MemoryFilesystem;
+import me.topchetoeu.jscript.filesystem.Mode;
+import me.topchetoeu.jscript.filesystem.RootFilesystem;
+import me.topchetoeu.jscript.lib.FilesystemLib;
 import me.topchetoeu.jscript.lib.Internals;
 
 public class Main {   
@@ -112,6 +116,11 @@ public class Main {
                 throw new EngineException("Couldn't open do.js");
             }
         });
+
+        var fs = new RootFilesystem(null);
+        fs.protocols.put("file", new MemoryFilesystem(Mode.READ_WRITE));
+
+        environment.global.define((Context)null, "fs", false, new FilesystemLib(fs));
     }
     private static void initEngine() {
         debugServer.targets.put("target", (ws, req) -> new SimpleDebugger(ws, engine));
diff --git a/src/me/topchetoeu/jscript/engine/Environment.java b/src/me/topchetoeu/jscript/engine/Environment.java
index 30a77a7..8bca1de 100644
--- a/src/me/topchetoeu/jscript/engine/Environment.java
+++ b/src/me/topchetoeu/jscript/engine/Environment.java
@@ -12,6 +12,7 @@ import me.topchetoeu.jscript.interop.Native;
 import me.topchetoeu.jscript.interop.NativeGetter;
 import me.topchetoeu.jscript.interop.NativeSetter;
 import me.topchetoeu.jscript.interop.NativeWrapperProvider;
+import me.topchetoeu.jscript.permissions.PermissionsManager;
 
 public class Environment {
     private HashMap<String, ObjectValue> prototypes = new HashMap<>();
@@ -21,6 +22,7 @@ public class Environment {
 
     public GlobalScope global;
     public WrappersProvider wrappers;
+    public PermissionsManager permissions;
 
     private static int nextId = 0;
 
diff --git a/src/me/topchetoeu/jscript/lib/FileLib.java b/src/me/topchetoeu/jscript/lib/FileLib.java
new file mode 100644
index 0000000..11c042f
--- /dev/null
+++ b/src/me/topchetoeu/jscript/lib/FileLib.java
@@ -0,0 +1,88 @@
+package me.topchetoeu.jscript.lib;
+
+import me.topchetoeu.jscript.engine.Context;
+import me.topchetoeu.jscript.engine.values.ArrayValue;
+import me.topchetoeu.jscript.engine.values.Values;
+import me.topchetoeu.jscript.filesystem.File;
+import me.topchetoeu.jscript.filesystem.FilesystemException;
+import me.topchetoeu.jscript.interop.Native;
+import me.topchetoeu.jscript.interop.NativeGetter;
+
+@Native("File")
+public class FileLib {
+    public final File file;
+
+    @Native public PromiseLib read(Context ctx, int n) {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                var buff = new byte[n];
+                var res = new ArrayValue();
+                int resI = file.read(buff);
+    
+                for (var i = resI - 1; i >= 0; i--) res.set(ctx, i, (int)buff[i]);
+                return res;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public PromiseLib write(Context ctx, ArrayValue val) {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                var res = new byte[val.size()];
+
+                for (var i = 0; i < val.size(); i++) res[i] = (byte)Values.toNumber(ctx, val.get(i));
+                file.write(res);
+
+                return null;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public PromiseLib close(Context ctx) {
+        return PromiseLib.await(ctx, () -> {
+            file.close();
+            return null;
+        });
+    }
+    @NativeGetter public PromiseLib pointer(Context ctx) {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                return file.getPtr();
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public PromiseLib setPointer(Context ctx, long ptr) {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                file.setPtr(ptr, 0);
+                return null;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @NativeGetter("length") public PromiseLib getLength(Context ctx) {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                long curr = file.getPtr();
+                file.setPtr(0, 2);
+                long res = file.getPtr();
+                file.setPtr(curr, 0);
+                return res;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @NativeGetter("mode") public PromiseLib getMode(Context ctx) {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                return file.mode().name;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+
+    public FileLib(File file) {
+        this.file = file;
+    }
+}
diff --git a/src/me/topchetoeu/jscript/lib/FilesystemLib.java b/src/me/topchetoeu/jscript/lib/FilesystemLib.java
new file mode 100644
index 0000000..8a9aaab
--- /dev/null
+++ b/src/me/topchetoeu/jscript/lib/FilesystemLib.java
@@ -0,0 +1,161 @@
+package me.topchetoeu.jscript.lib;
+
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.Stack;
+
+import me.topchetoeu.jscript.Filename;
+import me.topchetoeu.jscript.engine.Context;
+import me.topchetoeu.jscript.engine.values.ObjectValue;
+import me.topchetoeu.jscript.engine.values.Values;
+import me.topchetoeu.jscript.filesystem.EntryType;
+import me.topchetoeu.jscript.filesystem.File;
+import me.topchetoeu.jscript.filesystem.FileStat;
+import me.topchetoeu.jscript.filesystem.FilesystemException;
+import me.topchetoeu.jscript.filesystem.Mode;
+import me.topchetoeu.jscript.filesystem.RootFilesystem;
+import me.topchetoeu.jscript.filesystem.FilesystemException.FSCode;
+import me.topchetoeu.jscript.interop.Native;
+
+@Native("Filesystem")
+public class FilesystemLib {
+    public final RootFilesystem fs;
+
+    @Native public PromiseLib open(Context ctx, String _path, String mode) {
+        var filename = Filename.parse(_path);
+        var _mode = Mode.parse(mode);
+
+        return PromiseLib.await(ctx, () -> {
+            try {
+                if (fs.stat(filename.path).type != EntryType.FILE) {
+                    throw new FilesystemException(filename.toString(), FSCode.NOT_FILE);
+                }
+
+                var file = fs.open(filename.path, _mode);
+                return new FileLib(file);
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public ObjectValue ls(Context ctx, String _path) throws IOException {
+        var filename = Filename.parse(_path);
+
+        return Values.toJSAsyncIterator(ctx, new Iterator<>() {
+            private boolean failed, done;
+            private File file;
+            private String nextLine;
+
+            private void update() {
+                if (done) return;
+                if (!failed) {
+                    if (file == null) {
+                        if (fs.stat(filename.path).type != EntryType.FOLDER) {
+                            throw new FilesystemException(filename.toString(), FSCode.NOT_FOLDER);
+                        }
+
+                        file = fs.open(filename.path, Mode.READ);
+                    }
+
+                    if (nextLine == null) {
+                        while (true) {
+                            nextLine = file.readLine();
+                            if (nextLine == null) {
+                                done = true;
+                                return;
+                            }
+                            nextLine = nextLine.trim();
+                            if (!nextLine.equals("")) break;
+                        }
+                    }
+                }
+            }
+
+            @Override
+            public boolean hasNext() {
+                try {
+                    update();
+                    return !done && !failed;
+                }
+                catch (FilesystemException e) { throw e.toEngineException(); }
+            }
+            @Override
+            public String next() {
+                try {
+                    update();
+                    var res = nextLine;
+                    nextLine = null;
+                    return res;
+                }
+                catch (FilesystemException e) { throw e.toEngineException(); }
+            }
+        });
+    }
+    @Native public PromiseLib mkdir(Context ctx, String _path) throws IOException {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                fs.create(Filename.parse(_path).toString(), EntryType.FOLDER);
+                return null;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+
+    }
+    @Native public PromiseLib mkfile(Context ctx, String _path) throws IOException {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                fs.create(Filename.parse(_path).toString(), EntryType.FILE);
+                return null;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public PromiseLib rm(Context ctx, String _path, boolean recursive) throws IOException {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                if (!recursive) fs.create(Filename.parse(_path).toString(), EntryType.NONE);
+                else {
+                    var stack = new Stack<String>();
+                    stack.push(_path);
+
+                    while (!stack.empty()) {
+                        var path = Filename.parse(stack.pop()).toString();
+                        FileStat stat;
+
+                        try { stat = fs.stat(path); }
+                        catch (FilesystemException e) { continue; }
+
+                        if (stat.type == EntryType.FOLDER) {
+                            for (var el : fs.open(path, Mode.READ).readToString().split("\n")) stack.push(el);
+                        }
+                        else fs.create(path, EntryType.NONE);
+                    }
+                }
+                return null;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public PromiseLib stat(Context ctx, String _path) throws IOException {
+        return PromiseLib.await(ctx, () -> {
+            try {
+                var stat = fs.stat(_path);
+                var res = new ObjectValue();
+
+                res.defineProperty(ctx, "type", stat.type.name);
+                res.defineProperty(ctx, "mode", stat.mode.name);
+                return res;
+            }
+            catch (FilesystemException e) { throw e.toEngineException(); }
+        });
+    }
+    @Native public PromiseLib exists(Context ctx, String _path) throws IOException {
+        return PromiseLib.await(ctx, () -> {
+            try { fs.stat(_path); return true; }
+            catch (FilesystemException e) { return false; }
+        });
+    }
+
+    public FilesystemLib(RootFilesystem fs) {
+        this.fs = fs;
+    }
+}
diff --git a/src/me/topchetoeu/jscript/lib/FunctionLib.java b/src/me/topchetoeu/jscript/lib/FunctionLib.java
index ffa2ff7..77f5068 100644
--- a/src/me/topchetoeu/jscript/lib/FunctionLib.java
+++ b/src/me/topchetoeu/jscript/lib/FunctionLib.java
@@ -39,7 +39,7 @@ import me.topchetoeu.jscript.interop.Native;
         });
     }
     @Native(thisArg = true) public static String toString(Context ctx, Object func) {
-        return "function (...) { ... }";
+        return func.toString();
     }
 
     @Native public static FunctionValue async(FunctionValue func) {