The harden package has been deprecated.
Please use the shim for harden provided [SES][].
SES: https://github.com/Agoric/SES-shim/blob/master/packages/ses/README.md#harden
Since calling harden before lockdown provides no security guarantees, and
since a single harden should be shared throughout a realm, SES now provides
this singleton and exposes it globally.
The last coherent version of harden, prior to deprecation, was version
0.0.8.