  Software ecosystems (e.g., npm, PyPI) are the backbone of modern software
developments. Developers add new packages to ecosystems every day to solve new
problems or provide alternative solutions, causing obsolete packages to decline
in their importance to the community. Packages in decline are reused less
overtime and may become less frequently maintained. Thus, developers usually
migrate their dependencies to better alternatives. Replacing packages in
decline with better alternatives requires time and effort by developers to
identify packages that need to be replaced, find the alternatives, asset
migration benefits, and finally, perform the migration.
  This paper proposes an approach that automatically identifies packages that
need to be replaced and finds their alternatives supported with real-world
examples of open source projects performing the suggested migrations. At its
core, our approach relies on the dependency migration patterns performed in the
ecosystem to suggest migrations to other developers. We evaluated our approach
on the npm ecosystem and found that 96% of the suggested alternatives are
accurate. Furthermore, by surveying expert JavaScript developers, 67% of them
indicate that they will use our suggested alternative packages in their future
projects.
