\makeat{lett,oth}er are implicit in .cls and .sty files,

according to https://en.wikibooks.org/wiki/LaTeX/Creating_Packages

teckids2style.sty

@@ -65,11 +65,9 @@
 \RequirePackage[pdftex,unicode]{hyperref}%
 
 % Debian stretch compatibility glue
-\makeatletter%
 \ifx\f@nch@setoffs\@undefined%
  \let\f@nch@setoffs\fancy@setoffs%
 \fi%
-\makeatother%
 
 \definecolor{teckidsorangedark}{HTML}{FF6600}%
 \definecolor{teckidsorangelight}{HTML}{FF9955}%
@@ -180,7 +178,6 @@
 \teckidshdr{\headmark}%
 
 % Stuff to do at geometry changes
-\makeatletter%
 \def\teckidsgeometry{\@ifnextchar[\teckidsgeometry@BT\teckidsgeometry@BF}%
 \def\teckidsgeometry@BT[#1]{%
  \geometry{#1}%
@@ -190,9 +187,8 @@
  % restore lengths damaged during geometry change
  \setlength{\intextsep}{0pt}%
  % tell fancyhdr to redo its geometry calculations
- \makeatletter\f@nch@setoffs\makeatother%
+ \f@nch@setoffs%
 }%
-\makeatother%
 % run it initially
 \teckidsgeometry%
 
@@ -237,7 +233,6 @@
 
 % Listings
 
-\makeatletter%
 \newcounter{lstdumps}%
 \setcounter{lstdumps}{0}%
 \newcommand{\lstdumpname}{}%
@@ -370,7 +365,6 @@
 	xleftmargin=24pt,
 	numbersep=12pt,
 }%
-\makeatother%
 
 % Use pxfonts by default
 \renewcommand{\sfdefault}{pxss}%
@@ -388,18 +382,15 @@
 \newcommand{\Hair}{\kern.16667em}%
 
 % for lead paragraph before IT-Mieze
-\makeatletter%
 \newcommand{\keinumbruch}{\par\nobreak\@afterheading}%
-\makeatother%
 
-% for nice inline pictures in boxen with rounded corners
-\makeatletter%
 % fbox and ovalbox line will be inside the box
 \setlength{\fboxsep}{-2\fboxrule}%
 % to calculate horizontal padding inside the frame
 \newdimen{\inlinebildsep}%
 % to store dimensions of box without padding
 \newsavebox{\inlinebildbox}%
+% for nice inline pictures in boxen with rounded corners
 \newcommand{\inlinebild}[2][\@empty]{%
  % first, generate a box with square content and w/o padding
  \savebox{\inlinebildbox}{\ovalbox{\strut\hspace{1.25ex}}}%
@@ -423,10 +414,8 @@
   % right padding
   \hspace{\inlinebildsep}%
 }}%
-\makeatother%
 
 % for nice inline boxen with square corners
-\makeatletter%
 \newcommand{\inlinekasten}[1]{%
  % first, generate a box with square content and w/o padding
  \savebox{\inlinebildbox}{\fbox{\strut\hspace{1.25ex}}}%
@@ -448,9 +437,7 @@
   % right padding
   \hspace{\inlinebildsep}%
 }}%
-\makeatother%
 
-\makeatletter%
 % \hyperfootnotetext is what \footnotetext is supposed to be:
 % like \footnote except not rendering anything (it will not
 % generate a paragraph if you append % to all lines)
@@ -470,7 +457,6 @@
  }%
  % end of command
 }%
-\makeatother%
 
 % Berichtskopf mit Titel und Logo, Normalfall
 \newcommand{\teckidshead}[1]{%