diff --git a/ztl-mode.el b/ztl-mode.el
index 3a5e386..a7cc1fb 100644
--- a/ztl-mode.el
+++ b/ztl-mode.el
@@ -1,19 +1,16 @@
 ;;; ztl-mode.el --- Major mode for editing Ztl code -*- lexical-binding: t; -*-
 ;;
 ;; Licensed under the GPLv3 License.
-(require 'font-lock)
 
 (defvar ztl-keywords
-  '("fn" "to" "in" "is" "as" "use" "set" "if" "else" "for" "loop" "concurrent"
-    "while" "push" "pop" "return" "const" "type" "this" "eq" "ne" "do" "panic"
-    "mod" "not" "and" "or" "xor" "band" "bor" "bxor" "srl" "sll" "let")
+  '("fn" "to" "in" "is" "as" "use" "set" "if" "else"
+    "for" "loop" "concurrent" "while" "do" "exits" "exit"
+    "return" "const" "type" "this" "panic"
+    "break" "mod" "not" "and" "or" "print" "let")
   "Keywords in Ztl.")
 
 (defvar ztl-types
-  '("byte" "str" "int" "real"
-    "logical" "bool" "err"
-    "i8" "i16" "i32" "i64" "i128"
-    "f8" "f16" "f32" "f64" "f128")
+  '("byte" "str" "real" "bool" "err" "any")
   "Types in Ztl.")
 
 (defvar ztl-constants
@@ -21,41 +18,96 @@
   "Constants in Ztl.")
 
 (defvar ztl-font-lock-keywords
-  (list
-   ;; Constants
-   (cons (regexp-opt ztl-constants 'words) font-lock-constant-face)
-   ;; Keywords
-   (cons (regexp-opt ztl-keywords 'words) font-lock-keyword-face)
-   ;; Types
-   (cons (regexp-opt ztl-types 'words) font-lock-type-face)
-   ;; Structs (PascalCase)
-   '("\\b[A-Z][A-Za-z0-9_]*\\b" . font-lock-type-face)
-   ;; Numbers
-   '("\\b\\([0-9]+\\(?:\\.[0-9]*\\)?\\)\\b" . font-lock-number-face)
-   ;; Function calls
-   '("\\b\\([a-zA-Z_][a-zA-Z0-9_]*\\)\\s-*(" (1 font-lock-function-name-face))
-   )
-  "Font lock definitions for Ztl.")
+  `(
+    ;; Keywords
+    (,(regexp-opt ztl-keywords 'words) . font-lock-keyword-face)
 
-(defvar ztl-syntax-table
-  (let ((table (make-syntax-table)))
-    ;; Comments: C and C++ style
-    (modify-syntax-entry ?/ ". 14b" table)
-    (modify-syntax-entry ?* ". 23" table)
-    (modify-syntax-entry ?\n ">" table)
+    ;; Types
+    (,(regexp-opt ztl-types 'words) . font-lock-type-face)
+
+    ;; Constants
+    (,(regexp-opt ztl-constants 'words) . font-lock-constant-face)
+
+    ;; Structs: CamelCase identifiers
+    ("\\b[A-Z][a-zA-Z0-9_]*\\b" . font-lock-type-face)
+
+    ;; Floating point numbers
+    ("-?[0-9]+\\.[0-9]+" . font-lock-constant-face)
+
+    ;; Ints
+    ("-?[0-9]+" . font-lock-constant-face)
+
+    ;; Strings with double quotes
+    ("\"[^\"\n]*\"" . font-lock-string-face)
+
+    ;; Strings with backticks
+    ("`[^`]*`" . font-lock-string-face)
+
+    ;; Function definitions
+    ("\\_<fn\\>\\s-+\\(\\w+\\)(" (1 font-lock-function-name-face))
+
+    ;; Function calls
+    ("\\_<\\([a-zA-Z_][a-zA-Z0-9_]*\\)\\s-*(" (1 font-lock-function-name-face))
+
+    )
+  "Font lock keywords for Ztl mode.")
+
+(defvar ztl-mode-syntax-table
+  (let ((st (make-syntax-table)))
+    ;; C++-style comments
+    (modify-syntax-entry ?/ ". 14b" st)
+    ;; C-style comments
+    (modify-syntax-entry ?* ". 23" st)
     ;; Strings
-    (modify-syntax-entry ?\" "\"" table)
-    (modify-syntax-entry ?\\ "\\" table)
-    table)
-  "Syntax table for `ztl-mode'.")
+    (modify-syntax-entry ?\" "\"" st)
+    (modify-syntax-entry ?` "\"" st)
+    st)
+  "Syntax table for Ztl mode.")
 
-(define-derived-mode ztl-mode prog-mode "ZTL"
-  "Major mode for editing Ztl source files."
-  :syntax-table ztl-syntax-table
-  :group 'ztl
+(defun ztl-indent-line ()
+  "Indent current line as Ztl code."
+  (interactive)
+  (let ((indent (calculate-ztl-indent)))
+    (if (null indent)
+        (setq indent 0))
+    (indent-line-to indent)))
+
+(defun calculate-ztl-indent ()
+  "Calculate the proper indentation for the current line."
+  (save-excursion
+    (beginning-of-line)
+    (let ((pos (point-marker))
+          (indent 0))
+      (skip-chars-forward " \t")
+      (if (looking-at "\\s)\\|\\s(")
+          (setq indent 0)
+        (condition-case nil
+            (progn
+              (backward-up-list 1)
+              (while (and (> (point) (point-min))
+                          (progn
+                            (forward-line -1)
+                            (skip-chars-forward " \t")
+                            (or (looking-at "\\s<") ; comment
+                                (looking-at "\\s\"") ; string
+                                (looking-at "\\s$")))) ; skip to previous line
+                nil)
+              (setq indent (current-indentation))
+              (forward-line 0)
+              (skip-chars-forward " \t")
+              (if (looking-at "\\s(") ; opening brace
+                  (setq indent (+ indent tab-width))))
+          (error nil)))
+      indent)))
+
+(define-derived-mode ztl-mode prog-mode "Ztl"
+  "Major mode for editing Ztl code."
+  :syntax-table ztl-mode-syntax-table
   (setq-local font-lock-defaults '(ztl-font-lock-keywords))
-  (setq-local comment-start "//")
+  (setq-local comment-start "// ")
   (setq-local comment-end "")
+  (setq-local parse-sexp-ignore-comments t)
+  (setq-local indent-line-function 'ztl-indent-line)
   (setq-local syntax-propertize-function
               (syntax-propertize-rules
                ;; Line comments starting with //
@@ -65,5 +117,4 @@
 (add-to-list 'auto-mode-alist '("\\.ztl\\'" . ztl-mode))
 
 (provide 'ztl-mode)
-
-;; End of ztl-mode.el
+;;; ztl-mode.el ends here