Yea I don’t really agree with the rule that goroutines shouldn’t be started in libraries either. For example, say you are building a library to send metrics to

Yea I don’t really agree with the rule that goroutines shouldn’t be started in libraries either. For example, say you are building a library to send metrics to a metrics collector. For me it makes sense that your metrics library contains a buffer of metrics which it batches data together and sends to the metrics collector asynchronously. This would be implemented as having a library goroutine which batches and sends metrics data. I guess in theory your library could have a ‘Flush’ method and then if the application wants async flushing the application can start a goroutine which periodically calls flush. But then the application needs to know the ideal frequency to flush, how to handle failures to flush, how to backoff, etc. These things are probably better done by the library writer.