  We describe the \texttt{Imeall} package for the calculation and indexing of
atomistic properties of grain boundaries in materials. The package provides a
structured database for the storage of atomistic structures and their
associated properties, equipped with a programmable application interface to
interatomic potential calculators. The database adopts a general indexing
system that allows storing arbitrary grain boundary structures for any
crystalline material. The usefulness of the \texttt{Imeall} package is
demonstrated by computing, storing, and analysing relaxed grain boundary
structures for a dense range of low index orientation axis symmetric tilt and
twist boundaries in $\alpha$-iron for various interatomic potentials. The
package's capabilities are further demonstrated by carrying out automated
structure generation, dislocation analysis, interstitial site detection, and
impurity segregation energies across the grain boundary range. All computed
atomistic properties are exposed via a web framework, providing open access to
the grain boundary repository and the analytic tools suite.
