User groups, when the developer is active, can provide similar benefits. Two of the user groups I follow have significant developer participation (CONTAM build

User groups, when the developer is active, can provide similar benefits. Two of the user groups I follow have significant developer participation (CONTAM building airflow simulation, and the Sundials suite of numerical libraries). On both, users actually address the developers by name, make feature suggestions, and (in the case of Sundials, which has open code) suggest code fixes. Those groups also have more of a sense of community than the ones where the developers don't seem to spend much time.