Running out of memory during build due to too many concurrent threads

[VorpalBlade]

Using CircleCI the build box appears to have 35 threads. However, the system does not have enough memory to use all of those threads to build my project, resulting in running out of memory and sporadic internal compiler errors.

There should be a way to limit the maximum number of threads (passing -j to the build system). Alternatively, if this already is possible, I haven't found it in the documentation and would like to know how. (Plus the documentation should be updated to include it, if it is missing.)