From https://travis-ci.org/Pr0methean/BetterRandom/jobs/471236396, this is the entire log:
Worker information
hostname: d3e37a89-7c02-43d7-94af-ce8f2eea7dfe@7814.wjb-2
version: v4.4.0 https://github.com/travis-ci/worker/tree/80d1a9bbc1de0f176c56230ce9cc27f45ff1eb27
instance: 312d4f7e-499a-44cc-959e-dfe7cd664e0e travis-ci-osx10.11-xcode7.3-1480691248 (via amqp)
startup: 1m10.071491827s
curl: (60) SSL certificate problem: Invalid certificate chain
More details here: http://curl.haxx.se/docs/sslcerts.html
curl performs SSL certificate verification by default, using a "bundle"
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn't adequate, you can specify an alternate file
using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
the -k (or --insecure) option.
Download from https://build.travis-ci.org/filter/redirect_io.rb failed. Trying https://build.travis-ci.com/filter/redirect_io.rb ...
ruby: No such file or directory -- /Users/travis/filter.rb (LoadError)