Best Practices

We're planning to use Outsystems to support two existing apps from our newly acquired company. However, I like what I've seen of the UI tools so far and have a few questions:

1. We have alot of (complex) business code in C# DLLs that we'd like to keep on the server and expose it to OutSystems via WCF or WebAPIs. I know an Outsystsm app can consume this, but is it a good idea to proceed this way for almost any kind of business logic?

2. We wish to keep our existing stored procedures and move data in and out of our SQL Server databases using these. Again, also a good idea?

3. Can we host an OutSystems app on our local servers using our local databsaes, i.e. avoid the cloud completely?

What we're trying to do is to marginalize OutSystems for our web development as much as possible. We want to restrict it to UI only. Thus, if a set of data is needed to populate a combobox, it will be fed to the app by an API which uses a stored procedure. Then, if a choice is made in that combo box that filters the options in another combo box, our C# DLL would make that decision and serve up the filtered data.


I'm not the best person to answer your questions (someone from OutSystems is), but here are my two cents:

1) OutSystems is a great integrator. You can pretty much consume anything (sometimes more difficult than others). If you really want to take advantage of the platform you could start migrating all the complex business logic into Outsystems and focus on the logic itself and leave the code generation/refactoring to the platform. Only then you will be able to do quick changes and deploy them with 1-click;

2) You can keep using your stored procedures. Again the platform integrates natively with SQL Server / Oracle. More recently also with MySQL and DB2. So no reason to not take advantage of this;

3) You can totally avoid the cloud. 

My opinion, based on your short description, is you should maximize OutSystems for your web development.
To use it only for UI is a waste of money. 

Contact them directly. All the info here

If the existing code is hard to read, but working, you can start be doing what you said and have the new site up and running in minimum time. As time goes by and business changes (it always does), you can slowly move the logic to OutSystems.
1) well either via wcf/webapi it simply using the dll's in integration studio works as well.
2) stored-procedures can be used, but I strongly suggest to take advantage of crud-actions in outsystems for the simple inserting/updating
3) yup, no need for the cloud