  We introduce an R-matrix formulation of qq-characters and corresponding
Frenkel-Reshetikhin deformed W-algebras. The R-matrix featuring in the
construction is of Ding-Iohara-Miki (DIM) algebra, while the type of the
qq-character is determined by the network of Fock representations corresponding
to a web of 5-branes geometrically engineering a quiver gauge theory. Our
formulation gives a unified description of qq-characters of $A_n$ type and
their elliptic uplifts.
