I ran into the same with with the Workday SaaS connector. Tried a customizer and no evidence of it getting invoked. SaaS connectors are supposed to be written purely in TypeScript, however, from your logs you can see there is a bunch of stuff going on with invocation of Java classes, which is what the original connector framework is written in. My take is that they are selling some “SaaS” connectors which are really just proxys for using the old original Java based connectors if one exists already form your target application, therefore not invoking customizers. See my similar post here which never got any traction either: SaaS Connectivity: connector customizers - #5 by patrickboston