[lmm]

Morgan Stanley's version is open-source at https://github.com/morganstanley/optimus-cirrus , although I don't know how practical it is to actually run yourself. (They don't go quite as far as having the code itself be bitemporal and kept in the datastore, but most of the stuff in the article exists there)

[lesam]

Poetic that the most recent update is 6 months ago, a one line change adding a 'Lifecycle: Active' emoji to the Readme.