# How to make an extendable application **URL:** \ **Category:** Rails\ **Created:** [March 15, 2007, 10:37am UTC](https://www.ruby-forum.com/t/how-to-make-an-extendable-application/88887 "2007-03-15T10:37:44Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [March 15, 2007, 10:37am UTC](https://www.ruby-forum.com/t/how-to-make-an-extendable-application/88887/1 "2007-03-15T10:37:44Z")
Hey, This is a question aimed to all who have created their own CMSs. What is the correct way to go about making a reusable CMS? We all must be doing this, creating a new CMS for each site we do is prohibitvely expensive. Going through the Radiant source I see the majority of the code is kept in /app. Won’t this make it difficult to update the CMS code once it has been interleaved with the rest of the app? A plugin? What about a seperate set of migrations… we can’t mix the CMS migrations and app migrations… Engines? Seem to be the best solution at the moment… (What I currently use) Thoughts? How does everyone do this?.. or think they should be doing it? ta -henry ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [March 17, 2007, 1:36pm UTC](https://www.ruby-forum.com/t/how-to-make-an-extendable-application/88887/2 "2007-03-17T13:36:56Z")
Excellent question - I’m wondering the same thing myself - do you write a plugin with a generator that gets you going but then relies upon method calls IN the plugin’s library perhaps? The concept of reusable modules is one very nice feature of Django that I like - there’s got to be something similar in Rails! Wes On Mar 15, 4:36 am, “removed\_email\_address@domain.invalid” ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [March 25, 2007, 10:31pm UTC](https://www.ruby-forum.com/t/how-to-make-an-extendable-application/88887/3 "2007-03-25T22:31:13Z")
Hi Wes, I have the answer. The Rails ideology of convention over customisation is all well and good until you find an area lacking a convention. Engines is the way to go at the moment. I suspect principles will be taken from engines and made core eventually, if the poor author of Engines finally pursuades everyone they’re plugins and not an engines! cheers -h ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [March 26, 2007, 10:11pm UTC](https://www.ruby-forum.com/t/how-to-make-an-extendable-application/88887/4 "2007-03-26T22:11:34Z")
Thanks for the reply - yeah it looks like the engines guys take a beating. 🙂 Wes On Mar 25, 3:29 pm, “removed\_email\_address@domain.invalid” ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [March 27, 2007, 12:11am UTC](https://www.ruby-forum.com/t/how-to-make-an-extendable-application/88887/5 "2007-03-27T00:11:16Z")
All the engines plugin does is make the plugin system a little bit more flexible, really. Possibly some parts will be adopted, others certainly wont, since it exists to serve a slightly different development environment than that of the Rails core team. This is the nature of open source - we make it work the way that serves our needs best 🙂