[mlnox]

The UK government's digital services implement Open Standards for most of the code they develop. While this isn't something that third party vendors have to do, GDS/PDS/MOJDS/HMRCDigital are all rapidly reducing the amount of work external vendors do for government anyway.

https://github.com/alphagov

[bozho]

Yes, in the linked presentation I mention GDS as a good example. The US also has a lot of opensource projects.