Compilation fails on Windows

[EduardoMartinezLopez]

I'm not able to compile even a basic HelloWorld app with Juliac on Windows. The same example works fine on Linux.

I have a minimal project named HelloWorld in it's own directory of the same name.
julia file is in the "src" folder:

# src/HelloWorld.jl
module HelloWorld
function @main (args::Vector{String})
    println(Core.stdout,"Hello, World!")
    return 0
end
    
end

Project.toml:

 name = "HelloWorld"
 uuid = "386ce6dc-249a-4132-8b7b-795a0f20cf22"
 version = "0.1.0"
 authors = ["NMART122_FORD <nmart122+ford@ford.com>"]
 
 [apps]
 HelloWorld = {}

compilation command:

 juliac "C:\Users\NMART122\Documents\Julia\HelloWorld" --output-exe hello
(I have also tried without the full path to the project, no double quotes, etc.)

Output:

 C:\Users\NMART122\Documents\Julia>juliac "C:\Users\NMART122\Documents\Julia\HelloWorld" --output-exe hello
 Precompiling packages finished.
   0 dependencies successfully precompiled in 0 seconds
 
 The following 1 direct dependency failed to precompile:
 
 HelloWorld
 
 Error: Missing source file for Base.PkgId(Base.UUID("386ce6dc-249a-4132-8b7b-795a0f20cf22"), "HelloWorld"Precompiling packages finished.
   0 dependencies successfully precompiled in 0 seconds
 
 ERROR: The following 1 direct dependency failed to precompile:
 
 HelloWorld
 
 Error: Missing source file for Base.PkgId(Base.UUID("386ce6dc-249a-4132-8b7b-795a0f20cf22"), "HelloWorld"
 ERROR: Error encountered during instantiate/precompile of app project.
 Stacktrace:
  [1] error(s::String)
    @ Base .\error.jl:44
  [2] compile_products(recipe::JuliaC.ImageRecipe)
    @ JuliaC C:\Users\NMART122\.julia\packages\JuliaC\EFQEY\src\compiling.jl:105
  [3] _main_cli(args::Vector{String}; io::Base.TTY)
    @ JuliaC C:\Users\NMART122\.julia\packages\JuliaC\EFQEY\src\JuliaC.jl:191
  [4] _main_cli(args::Vector{String})
    @ JuliaC C:\Users\NMART122\.julia\packages\JuliaC\EFQEY\src\JuliaC.jl:182
  [5] main(ARGS::Vector{String})
    @ JuliaC C:\Users\NMART122\.julia\packages\JuliaC\EFQEY\src\JuliaC.jl:197
  [6] _start()
    @ Base .\client.jl:556

The HelloWorld app does work from the command line after being installed

Version info:

 julia> versioninfo()
 Julia Version 1.12.4
 Commit 01a2eadb04 (2026-01-06 16:56 UTC)
 Build Info:
   Official https://julialang.org release
 Platform Info:
   OS: Windows (x86_64-w64-mingw32)
   CPU: 28 × 13th Gen Intel(R) Core(TM) i7-13850HX
   WORD_SIZE: 64
   LLVM: libLLVM-18.1.7 (ORCJIT, alderlake)
   GC: Built with stock GC
 Threads: 1 default, 1 interactive, 1 GC (on 28 virtual cores)
 Environment:
   JULIA_CC = C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.44.35207\bin\Hostx64\x64\cl.exe