Right now, there is no way to set the scope of an environment variable in the web UI. All variables have RUN_AND_BUILD_TIME scope by default. It is only possible to configure the scope of environment variables by directly editing the app spec. The scope is then saved but not shown in the UI when making changes to these variables. This is confusing as you are never sure what the scope of a given variable is unless you look at the spec file.

Please, consider adding a select next to each environment variable which would allow us to choose one of the scopes: RUN_TIME, BUILD_TIME, or RUN_AND_BUILD_TIME