FYI, there are some Apache projects in C++ ( https://projects.apache.org/projects.html?language), and more in github ( https://github.com/apache?language=c%2B%2B), including incubator projects.
I summaries how typically they deal with the third parties and the release. - Apache Mesos (https://github.com/apache/mesos) has most third parties in release tar balls, along with patches. - Apache Kudu (https://github.com/apache/kudu) has multiple scripts to download and build third parties. - Apache NiFi - MiNiFi (https://github.com/apache/nifi-minifi-cpp) includes the whole codebase of third parties. Cheers, Zuyu
