Compiled Unreal source then linked project, forced to compile engine again?

Development Programming & Scripting
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Hello dear fellow developers,
I would need some help here:
I am afraid to be forced to compile all engine sources each time I do a little thing inside my project so I prefer to ask as the Engine with 32 Gb RAM takes around 8hours to compile which makes me lose entires days of work.
Here is how I did:

  1. Forked Engine source code from github to be at the same release version as the one we used from now on.
  2. Followed the tutorial to build the engine for "Development Editor " Win64
  3. Opening it using the Windows local debugger
  4. Trying to open my project, which was previously build with the “in launcher” Engine.
  5. Fail! versions don’t match, we need to recompile the project for the built version of Engine.
  6. Changed the Unreal version of the .uproject of our project to be the one built previously
  7. Generate Visual Studio Files
  8. Open the generated solution
  9. Tried to compile only the project
  10. Solution is starting to build whole Engine, which seems to take hours again.
  11. Stopped it to check if anything went wrong, came back to the Engine solution, trying to open it again with Windows local Debugger, the build start all over again, losing 8 hours again.

Now I am afraid to open the project solution and doing anything wrong again which would make me lose other days of works.

What is your experience with it? Any help would be very appreciated.

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hi , I usually work with source built engine, everything runs smoothly..
clone engine source code with [ --depth 1 ] argument and compile it only 2 hours on i9-13th cpu + 32G memory.
1, for first time opening your project, build it with console command to generate binaries folder and all modules (plugins modules)
2, daily coding and debug i only use LiveCoding and UE_LOG() , seldom touch the visual studio…

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  1. Make sure you are only building the UE5 project from the source solution, as it contains like 100 auxilliary projects which you rarely need to build yourself (the .dll are already provided by Setup.bat). This reduces compile time from 8H (whole solution) to about 1H (UE5 project only).

  2. Depending on configuration, it can sometimes happen that a subset of the engine will rebuild at least once the first time you launch a new configuration through a project solution, but this usually only happens once. I’m not sure its a bug or something, but I have experienced it on some machines. To be safe, be sure that you are launching the DeveloperEditor configuration, as if you launch DebugGame or some other config, it might compile a second binary of the source build under that other config. But if you launch a project with a configuration once, it shouldn’t rebuild the engine ever unless a change is detected in the source, and even new projects under the same configuration shouldn’t, at this point, rebuild the engine.

  3. Never clean the UE5 project or the source solution, it will trigger a rebuild.

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Thanks for your answers, I actually am trying to build UE5 only and the process build 5197 actions, which seems to be quite the same amount as when I built directly from the Local Windows Debugger (with UE5 as startup project).
I also, for test purpose, switched to Development|PS5 environment, then went back to Development Editor|Win64, aftre that the build process started all over again although I already built it during night.
This is really painful if I have to build all over again when I want to change environment. Am I missing something here again?