We have faced for some time some issues with compound integration with ChEMBL - specifically the loading of compound sets into ChEMBL for cross referencing, between for example, ChEBI, PDBe compounds, etc . The ChEMBL update cycle is relatively slow with respect to some other resources, and there is inevitable thrash with compounds not being present, especially for exciting new data. Without doing something different for compound integration, we were starting to face a scenario where we had a compound table with many millions of compounds without any bioactivity data, and following this the inevitable slowdown in searching, etc . We also had some issues facing us about curation of other people's primary data, changing compound structures, or their rendering, etc . So, we decided to set up an external system to resolve cross-references between various databases. This is a very simple Standard InChI lookup, containing compounds from resources such as ChEMBL, ChEBI, PDBe, Dru...