In-Process vs Standalone SolidWorks API — Which Should Your Automation Use?
If you’re building SolidWorks automation or evaluating how existing tools work, the architectural question of in-process versus standalone matters more than most developers initially expect. The choice affects which API calls you can make, how reliably the automation runs, and how much maintenance you’ll do when SolidWorks updates. This is worth understanding whether you’re writing your own add-in or evaluating third-party tools. The Two Execution Models In-process automation runs inside the SolidWorks process. An add-in is a DLL loaded by SolidWorks at startup. When your add-in code runs, it’s in the same memory space as SolidWorks itself. You communicate with the SolidWorks API through a direct object reference — no inter-process communication, no marshaling. ...