Basic Facts

Travis CI configuration is in file .travis.yml, and build scripts are in bin/build-*linux.sh. Only Linux builds are currently supported.
BUILD_TYPE=Debug jobs build and install MADNESS separately, before building TiledArray' BUILD_TYPE=Release jobs build MADNESS as a step of the TiledArray build.
MPICH and (BUILD_TYPE=Debug only) MADNESS installation directories are cached. Build scripts only verify the presence of installed directories, and do not update them if their configuration (e.g. static vs. shared, or code version) has changed. Thus it is admin's responsibility to manually wipe out the cache on a per-branch basis. It is the easiest to do via the Travis-CI web interface (click on 'More Options' menu at the top right, select 'Caches', etc.).
Rebuilding cache of prerequisites may take more time than the job limit (50 mins at the moment), so rebuilding cache can take several attempts. Since Travis-CI does not support forced cache updates (see e.g. https://github.com/travis-ci/travis-ci/issues/6410) if the job looks like it's going to time out we report success to Travis just so that it will store cache. Thus jobs that timed out will be falsely reported as successful (rather than errored)! When rebuilding cache it may be necessary to manually restart some build jobs to make sure that cache rebuild is complete (or, just to be sure, restart the whole build one time just to be sure all caches have been rebuilt). Again: this is only relevant when rebuilding caches (i.e. <5% of the time), otherwise there should be no need to restart jobs manually.

Debugging Travis-CI jobs

Local debugging

Follow the instructions contained in docker-travis.md .