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ADR024: web app language and framework selection


We are starting to develop a number of user-facing applications with web interfaces that need to be GOV.UK branded. In order to keep things consistent we want to pick a single programming language to write these in.

We’ve previously chosen Ruby on Rails as our desired framework in the previous ADR022. And whether or not it was a right choice, we decided to revisit and reconsider that choice.

The reason for that, is simply the direction GDS is heading at. It would appear that old components will be soon deprecated and the Frontend Community has no desire to support gems in the future. Saying that, we could have remain with Rails and delegate the component management to NPM. This would however increase the amount of possible maintenance work we would need to undertake, due to the use of nunjucks by the Design System team.

We questioned the need of running Rails application for something that essentially is a templating system for existing data and API.

After some more research, discussion with the head of the Frontend Community, members of the team and some others in GDS, the better choice would be Node for the following reasons:

  • It’s the way Frontend Community is heading at
  • It will be easier to rotate/onboard Frontend Developers
  • The initial applications are to be simple (thin layer between API calls and HTML parsing)
  • It’s light and essentially is JavaScript
  • It supports nunjucks which will help us in maintenance


We will use Node to create new user-facing applications that render a web interface for our service but will not be used to implement any significant ‘application logic’.




We should consider porting some of our existing applications over to Node.