\begin{document}
\begin{tikzpicture}[node distance=1em]
\node (s1) {\verb#>>|.#};
- \node (d1) [left=of s1.north,yshift=-3em] {\verb#delay#};
+ \node (d1) [left=of s1.north,yshift=-3em] {\verb#delay 500#};
\node (s2) [right=of s1.north,yshift=-3em] {\verb#>>=.# $\lambda x\shortrightarrow$};
- \node (wd) [left=of s2.north,yshift=-3em] {\verb#writeD#};
+ \node (wd) [left=of s2.north,yshift=-3em] {\verb#writeD D3 st#};
\node (rec) [right=of s2.north,yshift=-3em,fill=gray!15,label={[xshift=1em,label distance=-5pt]above:{\tiny interpreter}}] {\verb#blink (Not x)#};
\draw (s1.south) -- (d1.north);
\draw (s1.south) -- (s2.north);
\draw (s2.south) -- (wd.north);
\draw (s2.south) -- ([xshift=-1.5em]rec.north);
- \draw [->,dashed] ([xshift=-1.5em]rec.north) to [out=25,in=25] (s1.east);
+% \draw [->,dashed] ([xshift=-1.5em]rec.north) to [out=25,in=25] (s1.east);
\end{tikzpicture}
\end{document}