For libraries with physical barcodes on their items that do not match the barcode value in the record (and for whom re-barcoding is not feasible), the barcode transformation plugin hook allows any action with a barcode to be transformed via regex -- so if your physical barcode reads "T000123" but your record reads "123", you can remove the "T000." This transformation is also applied to searches of the barcode index. However, that library will still not find their record in a keyword search for "T000123." We should add a plugin hook to allow regex transformation of searches generally. While I imagine this will generally be used in tandem with the barcode transform hook, it seems more flexible to keep them distinct. This plugin hook would have the potential to cause a lot of confusion and really mess up searches if configured poorly, but I feel the utility outweighs the potential for error.