libdispatch has been open source since 2009<p><a href="https:&#x2F;&#x2F;libdispatch.macosforge.org&#x2F;post&#x2F;libdispatch-is-open-source&#x2F;" rel="nofollow">https:&#x2F;&#x2F;libdispatch.macosforge.org&#x2F;post&#x2F;libdispatch-is-open-...</a>