\documentclass{article}
\usepackage{tikz}
\usepackage{tikz-cd}
\usepackage{amsmath}

\begin{document}
	\[
	\begin{tikzcd}[
		column sep=scriptsize,
		execute at end picture={
		}
	 ]
		& |[name=myName]|foo \ar[dl]\\
		bar
	\end{tikzcd}
	\]
\end{document}

 \[
        	\begin{tikzcd}[
                        remember picture,
        		column sep=scriptsize,
        		execute at end picture={
        		}
        	 ]
                        &  foo \ar[dl]\\
        		bar
        	\end{tikzcd}
    \]
    \tikz[overlay, remember picture] \path (tikz@f@1-1-2) -- node[midway]{O} (tikz@f@1-2-1);

	\[
	\begin{tikzcd}[
	column sep=huge,
	row sep=huge,
	execute at end picture={
		\laxMorphism{(\tikzcdmatrixname-1-1)}{(\tikzcdmatrixname-1-3)}{$\TypeEras$}{$\TypePres$}
		\laxMorphism{(\tikzcdmatrixname-2-1)}{(\tikzcdmatrixname-2-3)}{$\TypeEras$}{$\TypePres$}
	}
	]
	\HardTyped \ar[d,hook] & & \SoftTyped \ar[d,hook]\\
	\HardProd & & \SoftProd
	\end{tikzcd}
	\]