diff --git a/paper/code/mutability.jl b/paper/code/mutability.jl
deleted file mode 100644
index b92ca7f..0000000
--- a/paper/code/mutability.jl
+++ /dev/null
@@ -1,13 +0,0 @@
-mutability(::Type) = IsNotMutable()
-function mutability(
-    T::Type,
-    op::Function,
-    args::Type...,
-)
-    if mutability(T) isa IsMutable &&
-        T == promote_operation(op, args...)
-        return IsMutable()
-    else
-        return IsNotMutable()
-    end
-end
diff --git a/paper/paper.tex b/paper/paper.tex
index dfe66b1..20de2e8 100644
--- a/paper/paper.tex
+++ b/paper/paper.tex
@@ -225,7 +225,17 @@ \subsection{Mutability fallback}
 returns \lstinline|IsMutable()| if \lstinline|T| is in the first category
 and \lstinline|IsNotMutable()| if \lstinline|T| is in the second category.
 Then we have the following fallback for \lstinline|mutability|:
-\jlinputlisting{code/mutability.jl}
+\begin{jllisting}
+mutability(::Type) = IsNotMutable()
+function mutability(T::Type, op::Function, args::Type...)
+    if mutability(T) isa IsMutable &&
+        T == promote_operation(op, args...)
+        return IsMutable()
+    else
+        return IsNotMutable()
+    end
+end
+\end{jllisting}
 
 \subsection{Minimal interface}
 In summary, for a type \lstinline|Foo| to implement the interface,