  We present an implementation of arbitrary-precision numerical integration
with rigorous error bounds in the Arb library. Rapid convergence is ensured for
piecewise complex analytic integrals by use of the Petras algorithm, which
combines adaptive bisection with adaptive Gaussian quadrature where error
bounds are determined via complex magnitudes without evaluating derivatives.
The code is general, easy to use, and efficient, often outperforming existing
non-rigorous software.
