prometeu-runtime/discussion/workflow/plans/PLN-0051-move-vm-runtime-into-services.md

id	ticket	title	status	created	ref_decisions	tags
PLN-0051	system-os-service-ownership-and-module-layout	Move VM Runtime Into Services	done	2026-05-14	DEC-0024	runtime os services module-layout vm window-manager logging

Briefing

Implement the mechanical module relocation required by DEC-0024: move VirtualMachineRuntime from the prometeu-system crate root into the services tree at services/vm_runtime.

This plan is intentionally behavior-preserving. It prepares the service layout for later ownership plans without moving logging, filesystem, or memcard state.

Source Decisions

• DEC-0024: VirtualMachineRuntime SHALL move to services/vm_runtime; old root paths MUST NOT remain available through compatibility reexports.

Target

Make VirtualMachineRuntime a service module while keeping the public type name unchanged and preserving current VM behavior.

The canonical implementation path after this plan is:

crates/console/prometeu-system/src/services/vm_runtime/

Dependencies

• Source decision: DEC-0024.
• No prior plan is required.
• This plan should run before PLN-0052, PLN-0053, and PLN-0054.

Scope

• Move crates/console/prometeu-system/src/virtual_machine_runtime.rs to crates/console/prometeu-system/src/services/vm_runtime.rs or equivalent module root under services/vm_runtime.
• Move the existing virtual_machine_runtime/ child modules under services/vm_runtime/.
• Update crates/console/prometeu-system/src/services/mod.rs to expose vm_runtime.
• Update crates/console/prometeu-system/src/lib.rs to export VirtualMachineRuntime from services::vm_runtime.
• Update internal module paths and tests directly.

Out of Scope

• Do not move LogService ownership.
• Do not move VirtualFS or MemcardService ownership.
• Do not move WindowManager.
• Do not introduce reexports or aliases for the old root module path.
• Do not change VM runtime behavior, syscalls, telemetry, logging semantics, or cartridge execution behavior.

Execution Plan

1. Move the VM runtime module files into src/services/vm_runtime/.
2. Register pub mod vm_runtime; from src/services/mod.rs.
3. Remove the root mod virtual_machine_runtime; declaration from src/lib.rs.
4. Export VirtualMachineRuntime through the services path.
5. Update SystemOS, tests, and any internal imports to use the new module location.
6. Run formatting and the affected Rust tests.

Acceptance Criteria

• VirtualMachineRuntime implementation lives under services/vm_runtime.
• No root virtual_machine_runtime module remains in prometeu-system.
• No compatibility reexport preserves the old root module path.
• Public type name VirtualMachineRuntime remains available where the crate API intentionally exposes it.
• Runtime behavior remains unchanged.

Tests / Validation

• Run cargo test -p prometeu-system.
• If workspace constraints make that too broad, run the narrowest available prometeu-system test target and record the exact command in implementation evidence.

Risks

• Module move churn can hide accidental import compatibility. Review must check that no old root module remains.
• Test modules may need path updates because they currently live under the VM runtime module tree.

Affected Artifacts

• crates/console/prometeu-system/src/lib.rs
• crates/console/prometeu-system/src/services/mod.rs
• crates/console/prometeu-system/src/services/vm_runtime/**
• Existing VM runtime tests moved with the module