If your build produces persistent artifacts such as screenshots, coverage reports, core files, or deployment tarballs, CircleCI can automatically saves and links them for you. You can find them on the 'artifacts' tab:
The documentation for using artifacts is here: https://circleci.com/docs/2.0/artifacts/
We don't make guarantees about how long artifacts are available for. If you're relying on them as a source of documentation / persistent content, we recommend deploying the output to a dedicated output target. Hosting static a site with something like GitHub pages or Netlify (https://www.netlify.com/) makes this easy and more reliable than grabbing an artifact from our S3 store.