CircleCI Build Forked Pull Requests
Today I learned that CircleCI does not build against forked pull requests by default. You have to enable it under 'Advanced Settings'.
This is important if your
.circleci/config.yml contains build steps like running an automated test suite, linter, or autoformatter. With this setting enabled, every PR goes through the same motions before human review, whether coming from inside or outside the project organization.