By default, Semaphore automatically halts the build if a command takes longer than an hour. This is to prevent cases like having left a debugger statement in the source code.
You can extend this timeout if needed. As project admin, go to project settings > Admin tab, and within "Build options" select the desired value of "Command timeout". Options range from 15 minutes to 180 minutes.
Semaphore Docs are open source — Edit on GitHub