let mkPackage = https://raw.githubusercontent.com/purescript/package-sets/psc-0.12.3-20190403/src/mkPackage.dhall let upstream = https://raw.githubusercontent.com/purescript/package-sets/psc-0.12.3-20190403/src/packages.dhall let overrides = { halogen = upstream.halogen ⫽ { version = "v5.0.0-rc.4" } , halogen-vdom = upstream.halogen-vdom ⫽ { version = "v6.1.0" } } let additions = {=} in upstream ⫽ overrides ⫽ additions