DSH Studio — supervising a local agent service with Tokio

[Moresyl]

I built DSH Studio, an MIT-licensed Tauri desktop shell that installs, runs, health-checks, and cleans up DeepSeek Harness on Windows, macOS, and Linux.

Tokio architecture

• tokio::process::Command launches both npm installation and the harness service without shell interpolation.
• stdout and stderr are streamed concurrently with AsyncBufReadExt and forwarded to a bounded event/log pipeline.
• oneshot channels carry readiness and stop signals; broadcast distributes typed lifecycle events to the desktop UI.
• tokio::select! races readiness, process exit, stop requests, and timeouts.
• A health loop performs bounded HTTP probes over TcpStream; repeated misses recycle the service.
• Restart backoff and shutdown remain asynchronous while platform guards reclaim the complete child tree.
• Integration tests use tokio::test and timeout to verify process-tree cleanup behavior.

The platform layer uses Windows Job Objects with kill-on-close and Unix process groups, while Tokio provides the shared asynchronous lifecycle model.

Source: https://github.com/Moresyl/dsh-studio
Supervisor: https://github.com/Moresyl/dsh-studio/blob/main/src-tauri/src/harness/supervisor.rs

Feedback on cancellation, readiness signaling, and lifecycle ownership is welcome.