Spotlights

Short tips, essays, and news about working with Go and software development. Most spotlights originate from my Go newsletter.

Container-Aware GOMAXPROCS (New in Go 1.25)

Before Go 1.25, GOMAXPROCS defaults to the number of available physical CPU cores at app startup time. Now it takes container limits into account and checks changes periodically.

New in Go 1.25: WaitGroup.Go()

WaitGroups are a means of synchronizing goroutines; yet the Add()/defer Done() idiom feels clumsy and is error-prone. A new method, Go(), puts an end to goroutine counting.

The Synctest Package (new in Go 1.25)

Tests that rely on time.Sleep() to test timings can be unreliable and slow. The synctest package introduces two antidotes: fake time and