John Lenton, senior engineering manager at Canonical, announced that Canonical would be moving away from CouchDB due to a few unresolvable issues Canonical ran into in production with CouchDB and the scale/requirements of the Ubuntu One service. Instead, says Lenton, Canonical will be moving to a custom data storage abstraction layer (U1DB) that is platform agnostic as well as datastore agnostic; utilizing the native datastore on the host device (e.g. SQLite, MySQL, API layers, "everything"). U1DB will be complete at some point after the 12.04 release."
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