  The inference of binary neutron star properties from gravitational-wave
observations requires the generation of millions of waveforms, each one
spanning about three order of magnitudes in frequency range. Thus, waveform
models must be efficiently generated and, at the same time, be faithful from
the post-Newtonian quasi-adiabatic inspiral up to the merger regime. A simple
solution to this problem is to combine effective-one-body waveforms with the
stationary phase approximation to obtain frequency-domain multipolar
approximants valid from any low frequency to merger. We demonstrate that
effective-one-body frequency-domain waveforms generated in post-adiabatic
approximation are computationally competitive with current phenomenological and
surrogate models, (virtually) arbitrarily long, and faithful up to merger for
any binary parameter. The same method can also be used to efficiently generate
intermediate mass binary black hole inspiral waveforms detectable by
space-based interferometers.
