Software adaptation aims at generating software pieces called adaptors to compensate interface and behavioural mismatch between components or services. This is crucial to foster reuse. So far, adaptation techniques have proceeded by computing global adaptors for closed systems made up of a fixed set of components. This is not satisfactory when the systems may evolve, with components entering or leaving it at any time, e.g., for pervasive computing. To enable adaptation on such systems, we propose tool-equipped adaptation techniques for the computation of open systems adaptors. Our proposal also support incremental adaptation to avoid the computation of global adaptors.