Learn how we increased the performance of the XC Metadata Services Toolkit (MST) by over 900%. Our first release performed too slowly with degrading performance with large record batches and we needed to enable the MST to process a library’s entire catalog in a reasonable amount of time on a common server. The MST was also intended to be extensible. Libraries will almost certainly want to customize this process in some way. Thus our second goal was to make it is as easy as possible for a developer to write a service which can be plugged into the MST.