For each deconstructible class of modules
D
\mathcal D
, we prove that the categoricity of
D
\mathcal D
in a big cardinal is equivalent to its categoricity in a tail of cardinals. We also prove Shelah’s Categoricity Conjecture for
(
D
,
⪯
)
(\mathcal D, \preceq )
, where
(
D
,
⪯
)
(\mathcal D, \preceq )
is any abstract elementary class of roots of Ext.