golang-github-fatih-semgroup-dev 1.2.0-2 (armhf binary) in ubuntu oracular

 semgroup provides synchronization and error propagation, for groups of
 goroutines working on subtasks of a common task. It uses a weighted
 semaphore implementation to make sure that only a number of maximum
 tasks can be run at any time.
 .
 Unlike golang.org/x/sync/errgroup, it doesn't return the first non-nil
 error, rather it accumulates all errors and returns a set of errors,
 allowing each task to fullfil their task.