Test-driven roles for pair programming

We propose a new model of two-person programming with a new structure based on test-driven development. In test driven development, developers follow two rules: "write new code only if an automated test has failed," and "eliminate duplication". The result is short, rapid development cycles in which an initially failing test is written to specify new functionality, code is written to make the test pass, and the code is then refactored to eliminate newly-introduced duplication. In our new model, the process of test-driven development is parallelized, with one member of the pair working primarily on tests, while the other works primarily on implementation. While developers can and will swap roles as it suits them, authoring tests and implementation gives structure to the developers\´ collaboration.