Using the compiler

You can download the latest compiler from the Download page.

To compile your Vellum script, put your script into a .vel file and run the compiler with the following command:

vellum.exe -f <path-to-your-script> -i <path-to-skyrim-scripts-folder>

-i / --import adds directories where the compiler looks for imported scripts and base types (.vel / .psc). See Imports.

To write the .pex to a different folder (for example your mod's Scripts directory):

vellum.exe -f Scripts\Source\MyScript.vel -o Scripts

To compile every .vel file under a directory (recursive by default):

vellum.exe -f Scripts\Source -i <path-to-skyrim-scripts-folder> -o Scripts

Only compile sources directly in that folder (not subdirectories):

vellum.exe -f Scripts\Source --no-recursive -i <path-to-skyrim-scripts-folder> -o Scripts

Batch mode prints per-file status and a summary. It fails before compiling if two source files share the same script name (same .pex stem).

If compilation succeeds, this produces a .pex file alongside your script (or in the directory given by -o / --output).

Run vellum.exe -h to get info about other compiler options.

For editor-integrated compile, see the VS Code extension.