The cBioPortal REST API is described using Swagger/OpenAPI, which allows one to generate a client in most programming languages. One can use the command line tool
curl for dowloading data on the command line or use another language such as
R to make visualizations. We list some common examples below, but if your language is not listed, there is likely a client generator available elsewhere (see e.g. https://swagger.io/tools/swagger-codegen/). Do reach out if you'd like us to add a language.