Our initial decision to use was primarily driven by [built-in support in Cloud Foundry](https://docs.cloudfoundry.org/buildpacks/python/index.html#pipenv). In practice, we have found that we still need to export the requirements file as part of the build process, removing the benefit.
Meanwhile, `poetry` appears to be the informal standard around TTS. It's relatively simple for a dev to switch between them, but we do value consistency across the organization.