Since 1998 the ALICE Offline Project has developed an integrated offline framework (AliRoot) and a distributed computing environment (AliEn) to process the data of the ALICE experiment. These systems are integrated with the LCG computing infrastructure, and in particular with the ROOT system and with the WLCG Grid middleware, but they also present a number of original solutions, which have been developed by the ALICE Offline Project to face the challenges specific to the ALICE, experiment. This talk will review the development and current status of the ALICE Offline. The presentation will describe how this environment has been tested during a series of exercises of increasing complexity carried on over the years. The status of readiness of the systems will be described, as well as the major challenges facing it at the eve of data taking. The lessons learned during this nine-year development will be described and analysed, and the development roadmap will be presented and discussed.

ALICE