We worked on MediaWiki-libs-Rdbms for a year (T343098: [epic] Data Persistence Hypothesis WE 3.2.1 and more) to improve developer experience of MediaWiki developers relying on rdbms library. Anecdotally, we heard positive feedback about the work but being able to measure satisfaction with the changes in a more structured way (probably as part of Developer Satisfaction Survey) could help us a lot with communication surrendering the work.

This can also guide us for further improvements in other areas of MediaWiki (for example for asking for other "components of mediawiki they find in need of improvement")