Pathfinder is a year old!
Pathfinder's been a wild ride, starting at a KITP workshop and sitting in alpha for a year before undergoing rapid dev at an intensive workshop at JHU, and is now published and has been out in the wild for about a year. In this time it seems to have found a stable audience and racked up in the ballpark of 100k uses, which is extremely gratifying! It was rather volatile until sometime mid-January this year, after which it has stabilized at around 500-600 queries a day (I'm guessing after the AAS meeting this year, where I gave a talk to the cosmic origins folks). It has also found its way into multiple paper acknowledgements, and seems to be fulfilling its primary role as a research tool to find relevant papers in a natural-language friendly way, and keep in touch with the ever-growing astronomy literature.
There's still a lot to be done - I'm not really interested in competing with services like scispace or AllenAI's paperfinder, and am interested instead in tracking research trends over time, looking for interesting use-cases for the paper embedding space, populating text with references, synthesizing information from large consortium paper releases, generating a 'daily digest'-like summary personalized to folks' research interests, mitigating biases due to in-group and missing citations, and identifying areas for future research / proposal writing. Some of this is actively being worked on, but there's still a lot to be done!