  We develop an integral form for the bispectrum in general single-field
inflation whose domain of validity includes models of inflation where the
background evolution is not constrained to be slowly varying everywhere. Our
integral form preserves the squeezed-limit consistency relation, allows for
fast evaluation of the bispectrum for all triangle configurations expediting
the efficient comparison of slow-roll violating models with data, and provides
complete and compact slow-roll expressions correct to first order in slow-roll
parameters. Motivated by the recent Planck results, we consider as an example a
sharp step in the warped-brane tension of DBI inflation and provide analytic
solutions for the peak of the resulting bispectrum. For the step in the warp
that reproduces the oscillations in the power spectrum favored by the Planck
data, the corresponding equilateral bispectrum is both extremely large and
highly scale dependent. The bispectrum serves as a means of distinguishing such
a model from alternative scenarios that generate otherwise indistinguishable
power spectra, such as a step in the potential in canonical single-field
inflation.
