But I do think it is the case at the GDS, as evidenced by the comment on this page:

> GDS is full of mostly django based systems, some legacy ruby and that's just the stuff from the last few years. Going back further there are various C# systems, the amount of separate systems is staggering, it's not too surprising costs add up

And this blog post:

> ...quickly agreed that rather than try to settle on a single one of those we'd build each tool using whichever technology would most quickly get us to a relatively-durable prototype, and then "federate" them. We started with the python-based framework Django for the Department pages, added Ruby on Rails for a suite of tools focussed on specific tasks, and used Sinatra (another ruby framework) to glue together our search.

https://gds.blog.gov.uk/2011/05/12/a-brief-overview-of-techn...