Communication techniques between a radio unit and a distributed unit via an application programming interface

Methods, systems, and devices for wireless communications are described. A remote unit (RU) of a base station may report, to a distributed unit (DU) of the base station, a message indicating that the RU supports an RU processing capability that is one of a first processing capability or a second processing capability. The first processing capability corresponds to additional physical layer signal processing at the RU than does the second processing capability. The RU may receive one or more uplink signals from a user equipment (UE) or accept one or more downlink signals from the DU, or both and process the one or more signals in accordance with the RU processing capability. The RU may forward the processed uplink signals from the RU to the DU via an application programming interface (API) that supports both the first processing capability and the second processing capability (e.g., a generalized API).