I’m working on a Rails 1 application. We’d like to upgrade it to Rails 3
4, but Rails 1 is so old that we think it would take a total rewrite to
upgrade. There are management and budget issues with a total rewrite. We
wouldn’t be able to deliver anything until the entire rewritten
So, we are searching for creative solutions to the upgrade problem. One
idea is to start rewriting the application in Rails 4 and run it
the Rails 1 application. As features are added to the Rails 4 version,
same feature in the Rails 1 version could be taken offline. Users would
a mix of the two versions. Some pages would be served by Rails 1 and
by Rails 4.
This would require both the Rails 1 and Rails 4 versions to use the same
So my question is, will this work? What problems with this approach
we be anticipating? We know it isn’t a perfect solution, but we’re
it’s good enough to drive the project forward.