MyPackage.jl/
├── test/
│   ├── Project.toml       # Test dependencies
│   ├── runtests.jl        # Test runner with filtering
│   ├── test_core.jl       # Core functionality tests
│   ├── test_aqua.jl       # Code quality checks
│   └── test_jet.jl        # Static analysis

@testitem "Core functionality" begin
    using MyPackage

    @test myfunction(1) == expected_value
    @test_throws ArgumentError myfunction(-1)
end

@testitem "Advanced feature" tags=[:advanced] begin
    using MyPackage

    @test advanced_function() works
end

@testitem "Aqua" tags=[:aqua] begin
    using Aqua
    using MyPackage

    Aqua.test_all(MyPackage;
        ambiguities=false,  # Optional: skip ambiguity checks
    )
end

@testitem "JET" tags=[:jet] begin
    using JET
    using MyPackage

    @test_opt target_modules=[MyPackage] myfunction(1)
    @test_call target_modules=[MyPackage] myfunction(1)
end