diff --git a/cli.py b/cli.py
index 7515db2..5fa47a2 100755
--- a/cli.py
+++ b/cli.py
@@ -16,6 +16,7 @@ You should have received a copy of the GNU General Public License
 along with pilang.  If not, see <https://www.gnu.org/licenses/>.
 """
 import sys
+from rtypes import goto
 from intern import main_class
 
 if len(sys.argv) == 1: # CLI loop
@@ -37,19 +38,46 @@ if len(sys.argv) == 1: # CLI loop
         except KeyboardInterrupt:
             print()
             continue
-        res = main.get_rstring(main.run_command(commandstr), errorsonly=False)
+        try:
+            res = main.get_rstring(main.run_command(commandstr), errorsonly=False)
+        except goto:
+            res = "Goto is not possible in CLI mode"
         if res != None:
             print(res)
 else:                  # File execution loop
+    # Initialise interpreter
     main = main_class()
+    # Parse argv
     if sys.argv[1] == "-c":
         del sys.argv[1]
         if len(sys.argv[1]) == 1:
             sys.exit(1)
+    # Save file line-by-line into list
     with open(sys.argv[1], mode="r") as f:
+        lines = []
         for line in f:
             if line[-1] == "\n":
                 line = line[:-1]
-            cmdres = main.get_rstring(main.run_command(line), errorsonly=True)
-            if cmdres:
-                print(cmdres)
+            lines.append(line)
+    # Execute file
+    linenum = 0
+    markers = {"start": 0}
+    while True:
+        try:
+            cmdres = main.get_rstring(main.run_command(lines[linenum]), errorsonly=True)
+            linenum += 1
+        except goto as gotoinstr:
+            if gotoinstr.define:
+                markers[gotoinstr.marker] = linenum + 1
+                linenum += 1
+                continue
+            else:
+                try:
+                    linenum = markers[gotoinstr.marker]
+                except KeyError:
+                    print("Invalid goto instruction (critical)")
+                    sys.exit(3)
+        except IndexError:
+            break
+        if cmdres:
+            print(cmdres)
diff --git a/errors.py b/errors.py
index 20086c1..27feedf 100644
--- a/errors.py
+++ b/errors.py
@@ -19,3 +19,4 @@ class nochsuchcmd:      pass
 class badarguments:     pass
 class nosuchmodule:     pass
 class nosuchvariable:   pass
+class inputeof:         pass
diff --git a/modules/builtin.py b/modules/builtin.py
index dedaa89..a863d5d 100644
--- a/modules/builtin.py
+++ b/modules/builtin.py
@@ -23,11 +23,17 @@ class builtin:
     def __init__(self, environ):
         self.commands = {
             "ret": self.cmd_ret,
+            "get": self.cmd_get,
+            "len": self.cmd_len,
             "catch": self.cmd_catch,
             "exit": self.cmd_exit,
+            "marker": self.cmd_marker,
+            "printnnl": self.cmd_printnnl,
             "print": self.cmd_print,
             "input": self.cmd_input,
             "set": self.cmd_set,
+            "inc": self.cmd_inc,
+            "dec": self.cmd_dec,
             "del": self.cmd_del,
             "eval": self.cmd_eval,
             "cmp": self.cmd_cmp,
@@ -44,6 +50,20 @@ class builtin:
     def cmd_ret(self, args):
         return " ".join(args)
     
+    def cmd_get(self, args):
+        if len(args) != 2:
+            return errors.badarguments
+        try:
+            return args[0][int(round(float(args[1])))]
+        except:
+            return errors.badarguments
+    
+    def cmd_len(self, args):
+        result = 0
+        for arg in args:
+            result += len(arg)
+        return str(result)
+    
     def cmd_catch(self, args):
         if args == []:
             self.environ.catch = not self.environ.catch
@@ -63,16 +83,33 @@ class builtin:
         except IndexError:
             return errors.badarguments
     
+    def cmd_marker(self, args):
+        if len(args) != 2:
+            return errors.badarguments
+        if args[0] == "set":
+            raise rtypes.goto(marker=str(args[1]), define=True)
+        elif args[0] == "goto":
+            raise rtypes.goto(marker=str(args[1]), define=False)
+        else:
+            return errors.badarguments
+    
+    def cmd_printnnl(self, args):
+        return self.cmd_print(args, nonline=True)
+    
     def cmd_print(self, args, nonline=False):
         for arg in args:
-            print(arg, end="")
+            print(arg, end="", flush=nonline)
         if not nonline:
             print()
         return rtypes.success
     
     def cmd_input(self, args):
         self.cmd_print(args, nonline=True)
-        return input()
+        try:
+            return input()
+        except EOFError:
+            print()
+            return errors.inputeof
     
     def cmd_set(self, args):
         if len(args) != 2:
@@ -80,6 +117,22 @@ class builtin:
         self.environ.variables[args[0]] = args[1]
         return rtypes.success
     
+    def cmd_inc(self, args):
+        if len(args) == 1:
+            args.append(1)
+        if not len(args) == 2:
+            return errors.badarguments
+        try:
+            self.environ.variables[args[0]] = str(float(self.environ.variables[args[0]]) + float(args[1]))
+        except KeyError:
+            return errors.badarguments
+        return rtypes.success
+    
+    def cmd_dec(self, args):
+        if len(args) < 2:
+            args.append(1)
+        return self.cmd_inc(args[0], -args[1])
+    
     def cmd_del(self, args):
         # Check if variable exists
         for arg in args:
@@ -120,11 +173,9 @@ class builtin:
                 return matches
         except ValueError:
             return errors.badarguments
-        # Evaluate list of commands
+        # Evaluate list of commands if comparisation matches
         if matches:
-            for command in commands:
-                lastres = self.environ.evaluate(command)
-            return lastres
+            return self.cmd_eval(commands)
         else:
             return rtypes.fail
     
diff --git a/modules/time.py b/modules/time.py
new file mode 100644
index 0000000..9b860f9
--- /dev/null
+++ b/modules/time.py
@@ -0,0 +1,45 @@
+"""
+This file is part of pilang.
+
+pilang is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+pilang is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with pilang.  If not, see <https://www.gnu.org/licenses/>.
+"""
+import time as pytime
+import rtypes
+
+class time:
+    def __init__(self, environ):
+        self.commands = {
+            "sleep": self.cmd_sleep
+            }
+        self.environ = environ
+    
+    
+    def processor(self, command, args):
+        try:
+            return self.commands[command](args)
+        except KeyError:
+            return errors.nochsuchcmd
+    
+    def cmd_sleep(self, args):
+        if len(args) != 1:
+            return errors.badarguments
+        try:
+            pytime.sleep(float(args[0]))
+        except ValueError:
+            return errors.badarguments
+        return rtypes.success
+
+
+def adder(registerer):
+    registerer(time)
diff --git a/rstrings.py b/rstrings.py
index ea4ad8b..0e2a799 100644
--- a/rstrings.py
+++ b/rstrings.py
@@ -20,5 +20,6 @@ rstrings = {
     "nochsuchcmd": "No such command",
     "nosuchmodule": "No such module",
     "nosuchvariable": "No such variable",
-    "badarguments": "Bad arguments"
+    "badarguments": "Bad arguments",
+    "inputeof": "EOF in stdin",
         }
diff --git a/rtypes.py b/rtypes.py
index a5267c2..37cbb64 100644
--- a/rtypes.py
+++ b/rtypes.py
@@ -16,3 +16,8 @@ along with pilang.  If not, see <https://www.gnu.org/licenses/>.
 """
 class success: pass
 class fail:    pass
+
+class goto(Exception):
+    def __init__(self, marker, define:bool=False):
+        self.define = define
+        self.marker = marker