OutSystems Detach Process: What Really Happens (And Why It's Not Enough)
A technical deep-dive into the OutSystems detach process - what you actually get, common pitfalls, and why there is a better approach to leaving the platform.
What the documentation says vs. what actually happens
OutSystems offers a "detach" process that lets you extract the generated source code from your applications. On paper, this sounds like your exit strategy. In practice, it's the beginning of a very long headache.
We've talked to teams who've been through it. Here's what they found.
Step 1: The detach itself
OutSystems generates .NET code (C#) from your visual models. The detach process gives you this generated code as a Visual Studio solution (.sln file).
Requirements:
- You must be current on payments per your MSA
- You must provide written notice before your contract termination date
- Self-hosted environments are simpler; cloud-hosted adds complexity
"Does anybody have experience in detaching their code from the OutSystems platform? We are self-hosted, so it should potentially be easier. I have read the OutSystems how-to, but I'm concerned that it might be more complex than anticipated."
— r/OutSystems, Sep 2023
That concern is justified.
Step 2: Getting it to compile
The generated .NET solution rarely compiles out of the box. Common issues:
Missing DLL references OutSystems runtime libraries and third-party extensions are dynamically loaded. After detach, these references are often broken.
"After getting the code to compile, will my application function correctly? No. Getting the solution to compile is just the first part of the problem. During execution, DLLs from OutSystems or third parties are dynamically loaded, which might not have been configured correctly."
— lowcodedetach.com FAQ
Namespace conflicts Modules that reference each other can create circular dependencies and missing namespace errors.
"The name 'ssUsers' does not exist in the current context."
— Suriyakala S, OutSystems Forum, Jan 2025 (actively detaching)
External resource paths References to external files, CSS, JavaScript, and images break because they pointed to OutSystems-managed paths.
"I recently had the opportunity, unfortunately, to perform some detach processes. We encountered some issues not covered in this guide, particularly related to the path to external resources."
— Gonçalo Ferraria, OutSystems Forum, Jan 2025
Step 3: Getting it to run
Even after compilation, the application likely won't run correctly:
- Database connections need to be reconfigured — the generated code assumes OutSystems database naming conventions
- Authentication was handled by the OutSystems Users module — you need to replace it
- Timer processes (BPT) relied on OutSystems scheduling infrastructure
- Forge components are OutSystems-specific and won't work outside the platform
Step 4: The data problem
If you're cloud-hosted, OutSystems won't give you a database backup. You get read-write SQL access and have to export the data yourself.
"Biggest headache was getting the data locally, as they (OutSystems) won't provide you with a database backup. Only a SQL user with read-write access. We resolved this by creating our own C# import program, and some SQL magic dropping foreign keys, running inserts, recreate foreign keys."
— r/OutSystems, Sep 2023
Step 5: Maintaining the result
Congratulations — you now have a working (sort of) .NET application built from auto-generated code that no human wrote. It looks like this:
- Hundreds of classes with machine-generated names
- Business logic buried in auto-generated action chains
- No documentation
- No tests
- No clear separation of concerns
"If we want to get the C# code to run it ourselves, we have to pay loads of money, and then start maintaining the generated code directly OURSELVES, which means the whole IT department has to quickly adapt to the spaghetti-like codebase."
— r/programming, Dec 2023
This is not a maintainable codebase. It's a liability dressed up as source code.
The honest assessment
The detach process does work — technically. Teams have successfully detached and gotten applications running. But what you end up with is:
- ✅ Independence from OutSystems licensing
- ❌ A codebase nobody can maintain
- ❌ Months of work just to get it running
- ❌ No path to improvement or new features
- ❌ Technical debt that makes the original OutSystems problems look small
"In all the cases we have seen, it was faster and therefore cheaper just to rebuild the application in a new, open platform."
There's a better approach
The fundamental problem with the detach is that it works at the wrong level. It gives you the generated output — machine code that was never meant for human eyes. No wonder teams spend months just getting it to compile.
What if you could skip the spaghetti entirely?
We've developed proprietary technology that understands your OutSystems applications at a deeper level than the generated code. We recover the complete logic — data models, business rules, workflows, integrations — and produce a clear blueprint. Then we rebuild in clean, modern code.
No spaghetti. No guessing. No 12-month blind rebuild.
Book a free assessment → — We'll analyze your OutSystems applications and show you exactly what's inside.