At times, template designers may wish to set environment variables in the projects created from their templates. For example, if a template designer adds 3rd-party software like aws-cli to the template and wishes to preconfigure this software, they might want to set AWS_CONFIG_FILE to a file shared by all current and future users under /cloud/project.
This can be accomplished in RStudio projects by creating a .Renviron file in /cloud/project. Environment variables defined here will be defined in both R and bash shell sessions for future users.
More information about .Renviron files can be found in R Startup Environments.