# Design guidance for for Plug-in/Engine based application **URL:** \ **Category:** Engines\ **Created:** [May 12, 2007, 8:00am UTC](https://www.ruby-forum.com/t/design-guidance-for-for-plug-in-engine-based-application/103978 "2007-05-12T08:00:43Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![dondi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/8797f3/32.png) [@dondi](https://www.ruby-forum.com/u/dondi)\ **Post date:** [May 12, 2007, 8:00am UTC](https://www.ruby-forum.com/t/design-guidance-for-for-plug-in-engine-based-application/103978/1 "2007-05-12T08:00:43Z")
Hello, Is the following app suitable to a Plug-in based app architecture? I have been researching this for some time and have not found a clear-cut perspective to date. I did receive some generous feedback from a post on Railsforum suggesting an Engines-based approach, so now I am trying to further explore that approach. All thoughts are appreciated. App outline: 1. 5 module complex work flow system to assist in automobile design: module 1 - spaceframe, module 2 - drivetrain, module 3 - aerodynamics, module 4 - environmentals, module 5 - controls 1. Each of these modules are fairly complex and should themselves be implemented as n-step wizards 2. The modules can either be used in sequence to complete an end-to-end design project (XYZ Concept Car), or they can be used independently to assist in the design of a single subsystem or multiple independent subsystems. i.e., a project can encompass one or more modules 3. Some modules will produce data that other modules can use to complete their particular function (for example: controls module needs to know about drive train and environmentals) 4. A user can have many projects (i.e., a portfolio) Questions: 1. Is an app like this best suited to an Engines/Plug-in or conventional app architecture? 2. What’s the best way to organize such an application? 1 app? 5 independent Rails applications orchestrated by a sixth app? 1 app with 5 plug-ins?, …? Thoughts? Thx, Dondi.