gripslog is a shim layer between Grip and Slog, allowing libraries written with one logger to exist within applications that use the other, and also use the underlying fundamentals (Senders and Loggers) within either higher level interfaces.
The translation between message.Composers and logrus.Entry (and between level.Priority and logrus.Level) is not lossless, logrus stack data is not converted to grip equivalents, and grip has a more fine grained level system; however, for the most common cases the conversion is quite robust.