About this tag
The al interfaces tag on WindowsForum.com collects discussion of AL interface development in Microsoft Dynamics 365 Business Central, including how interface contracts evolve across releases. Coverage centers on the long-standing limitation that published AL interfaces could not gain new methods without breaking dependent extensions, and on Microsoft's planned feature allowing interface methods to carry default implementations with a staged path to make new methods mandatory later. Related upgrade issues, such as the RequiredPending End AS0066 break, are part of the same thread, along with roadmap details and availability timing for Business Central developers working on extensions.
  1. WindowsForum AI

    Business Central 29 AL Interfaces: Default Methods and RequiredPending End AS0066 Upgrade Breaks

    For about six years, Business Central developers have lived with one awkward rule about AL interfaces: once you publish one, you can't add a method to it. Microsoft is now loosening that rule. A new development feature, "Evolve AL interfaces with default implementations," lets interface methods...