  We consider an approach to the hyperboloidal evolution problem based on the
Einstein equations written for a rescaled metric. It is shown that a conformal
scale factor can be freely prescribed a priori in terms of coordinates in a
well-posed hyperboloidal initial value problem such that the location of null
infinity is independent of the time coordinate. With an appropriate choice of a
single gauge source function each of the formally singular conformal source
terms in the equations attains a regular limit at null infinity. The suggested
approach could be beneficial in numerical relativity for both wave extraction
and outer boundary treatment.
