1. A method comprising: displaying, at a client device, a first version of a feature in a file or having a first format suitable for an editor; invoking a merge service to request merging of a modification to the file with a master file, the master file supporting a second version of the feature not supported on the client device or the master file supporting a second format different from the first format, wherein invoking the merge service comprises providing, from the client device to the merge service, a modification request to an individual modification function and a location identifier that identifies a location of the modification within the file, wherein the individual modification function performs adding a comment.