# Using enzyme with SystemJS If you are using a test runner that runs code in a browser-based environment, you may be using [SystemJS]() in order to bundle your React code. Prior to enzyme 3.0 there were some issues with conditional requires that were used to maintain backwards compatibility with React versions. With enzyme 3.0+, this should no longer be an issue. If it is, please file a GitHub issue or make a PR to this documentation with instructions on how to set it up.