D3/D7 branes at singularities: Constraints from global embedding and moduli stabilisation

In the framework of type IIB string compactifications on Calabi-Yau orien-tifolds we describe how to construct consistent global embeddings of models with fractional D3-branes and connected 'flavour' D7-branes at del Pezzo singularities with moduli stabilisation. Our results are applied to build an explicit compact example with a left-right symmetric model at a dP₀ singularity which features three families of chiral matter and gauge coupling unification at the intermediate scale. We show how to stabilise the moduli obtaining a controlled de Sitter minimum and spontaneous supersymmetry breaking. We find an interesting non-trivial dynamical relation between the requirement of TeV-scale soft terms and the correct phenomenological values of the unified gauge coupling and unification scale.