diff --git a/PyTeX b/PyTeX
index dbdd99c..6c0dee2 160000
--- a/PyTeX
+++ b/PyTeX
@@ -1 +1 @@
-Subproject commit dbdd99cc3d6e02b0cfadb1d337f6b85c5f52a9b5
+Subproject commit 6c0dee2511b1e28a8af3ceefa2219fc5135c8221
diff --git a/build.py b/build.py
index 962a773..c61e709 100644
--- a/build.py
+++ b/build.py
@@ -6,7 +6,7 @@ from datetime import *
 sys.path.insert(0, 'PyTeX/')
 
 from package_formatter import PackageFormatter
-from replacements import make_default_commands
+from class_formatter import ClassFormatter
 from git_version import git_describe, get_latest_commit
 
 BUILD_DETAILS = [
@@ -41,14 +41,21 @@ def build(build_dir: str):
     if git.Repo().is_dirty():
         extra_header += ['WARNING: Local changes to git repository detected.',
                          '         The build will not be reproducible (!)']
-    num_files = 0
+    num_packages = 0
+    num_classes = 0
     for file in input_root.rglob('*.pysty'):
-        num_files += 1
+        num_packages += 1
         formatter = PackageFormatter(package_name=file.with_suffix('').name, extra_header=extra_header)
         print('[PyTeX] Writing file {}'.format(formatter.file_name))
-        make_default_commands(formatter)
-        formatter.format_package(file, Path('./').resolve() / build_dir / str(file.parent.relative_to(input_root)))
-    print(f'[PyTeX] Successfully built {num_files} packages in {build_dir}/')
+        formatter.make_default_macros()
+        formatter.format_file(file, Path('./').resolve() / build_dir / str(file.parent.relative_to(input_root)))
+    for file in input_root.rglob('*.pycls'):
+        num_classes += 1
+        formatter = ClassFormatter(class_name=file.with_suffix('').name, extra_header=extra_header)
+        print('[PyTeX] Writing class file {}'.format(formatter.file_name))
+        formatter.make_default_macros()
+        formatter.format_file(file, Path('./').resolve() / build_dir / str(file.parent.relative_to(input_root)))
+    print(f'[PyTeX] Successfully built {num_packages} packages and {num_classes} classes in {build_dir}/')
 
 
 if __name__ == "__main__":
diff --git a/packages/lecture-notes/script.cls b/packages/lecture-notes/script.pycls
similarity index 75%
rename from packages/lecture-notes/script.cls
rename to packages/lecture-notes/script.pycls
index acabba1..2cbeb28 100644
--- a/packages/lecture-notes/script.cls
+++ b/packages/lecture-notes/script.pycls
@@ -1,55 +1,49 @@
-\NeedsTeXFormat{LaTeX2e}
-\ProvidesClass{mkessler-script}[2021/03/31 Write up lecture notes as script]
+__HEADER__(Write up lecture notes as script)
 
-%%%%Options of the package
-\newif\ifenglish\englishtrue
-\DeclareOption{english}{\englishtrue}
-\DeclareOption{german}{\englishfalse}
+__LANGUAGE_OPTIONS__
 
-\newif\ifshowversion\showversiontrue
-\DeclareOption{show version}{\showversiontrue}
-\DeclareOption{hideversion}{\showversionfalse}
+__NEW_IF__(showversion,true)
+\DeclareOption{show version}{__SET_IF__(showversion,true)}
+\DeclareOption{hideversion}{__SET_IF__(showversion,false)}
 
-\newif\iffancyfoot\fancyfootfalse
-\DeclareOption{fancyfoot}{\fancyfoottrue}
-
-\newif\ifgitversion\gitversionfalse
-\DeclareOption{git}{\gitversiontrue}
-
-\ProcessOptions\relax
+__NEW_IF__(fancyfoot,false)
+\DeclareOption{fancyfoot}{__SET_IF__(fancyfoot,true)}
 
 
+__NEW_IF__(gitversion,false)
+\DeclareOption{git}{__SET_IF__(gitversion,true)}
+
+__END_OPTIONS__
 
 \RequirePackage{xifthen}
 
 %%%%Define command to set metainformation of document
 %Set the course
-\def\@course{\ClassError{mkessler-script}{No \noexpand\course given}{See documentation for details}}%
+\def\@course{__ERROR__(No \noexpand\course given){See documentation for details}}%
 \DeclareRobustCommand*{\course}[1]{\gdef\@course{#1}}
 
-\def\@lecturer{\ClassError{mkessler-script}{No \noexpand\lecturer given}{See documentation for details}}%
+\def\@lecturer{__ERROR__(No \noexpand\lecturer given){See documentation for details}}%
 \def\@lecturertitle{}
 \DeclareRobustCommand*{\lecturer}[2][]{
     \gdef\@lecturer{#2}
-    \gdef\@lecturertitle{\ifenglish Lecturer\else\ifthenelse{\isempty{#1}}{Dozent}{Dozentin}\fi}{}
+    \gdef\@lecturertitle{__IF__(english) Lecturer\else\ifthenelse{\isempty{#1}}{Dozent}{Dozentin}\fi}{}
 }
 
 %Set the assistant
-\newif\ifprintassistant\printassistantfalse
+__NEW_IF__(printassistant,false)
 \def\@assistant{}%
 \def\@assistantitle{}
 \DeclareRobustCommand*{\assistant}[2][]{
-    \printassistanttrue
+    __SET_IF__(printassistant,true)
     \gdef\@assistant{#2}
-    \gdef\@assistanttitle{\ifenglish Assistant\else\ifthenelse{\isempty{#1}}{Assistent}{Assistentin}\fi}
+    \gdef\@assistanttitle{__IF__(english) Assistant\else\ifthenelse{\isempty{#1}}{Assistent}{Assistentin}\fi}
 }
 
 %%%%Load base class article
 \LoadClass{article}
 
-
-\ifshowversion
-    \ifgitversion
+__IF__(showversion)
+    __IF__(gitversion)
         \RequirePackage[dirty={ (local changes have been made!)}]{gitinfo2}
     \fi
 \fi
@@ -73,7 +67,7 @@
         \@lecturertitle \\
         {\sc \@lecturer} \\
       \end{tabular}\par
-    \ifprintassistant
+    __IF__(printassistant)
     \vskip 1em%
         \begin{tabular}[t]{c}%
         \@assistanttitle \\
@@ -82,17 +76,17 @@
     \fi
     \vskip 1em%
         \begin{tabular}[t]{c}%
-        \ifenglish Notes\else Mitschrift\fi \\
+        __IF__(english) Notes\else Mitschrift\fi \\
         {\sc \@author} \\
         \end{tabular}
         \par}%
-    \ifshowversion
+    __IF__(showversion)
     \vskip 3em%
         \begin{tabular}[t]{c}%
         {\small Version} \\
-        \ifgitversion
+        __IF__(gitversion)
             git: \gitFirstTagDescribe\\
-            \ifenglish compiled\else kompiliert\fi:
+            __IF__(english) compiled\else kompiliert\fi:
         \fi\today\,\currenttime \\
         \end{tabular}\par
     \fi
@@ -131,7 +125,7 @@
 
 %%%% These are the fancy headers
 
-\iffancyfoot
+__IF__(fancyfoot)
     \RequirePackage{fancyhdr}
     \pagestyle{fancy}