Backend

The backend owns generated project layout and .NET toolchain execution.

Responsibilities

• write Program.cs
• write tsonic.csproj
• place emitted .cs files
• lay out package-shaped generated source trees where needed
• invoke dotnet build, publish, test, and pack
• manage NativeAOT vs managed output differences

Output modes

• executable
• managed library
• NativeAOT shared library
• NativeAOT static library

Important inputs

• compiler-emitted C#
• workspace DLL and NuGet references
• framework references
• runtime overlays from source-package metadata
• local package ownership mode (source vs dll)

Package-shaped generated source

When local or installed source packages are emitted into the closure, the backend preserves package hierarchy rather than flattening everything into one directory.

That is why generated output often includes paths like:

generated/node_modules/@tsonic/nodejs/...
generated/node_modules/@acme/domain/...

That is intentional. It preserves module ownership and avoids collisions.

Local DLL boundaries

When a local package reference uses mode: "dll", the backend:

• builds the referenced project first
• references its assembly boundary
• avoids generating that package’s source again into the same closure