Is Pulumi still using

dep

v0.4.1?

Yes - see https://github.com/pulumi/pulumi/blob/master/build/travis/install-common-toolchain.sh

Thanks. Is there a reason not to upgrade to 0.5 besides not having got round to it yet? The resolution speed is substantially faster for a large dependency graph

No. Would be nice to get to

0.5

.