The shared home for spawning managed child-process trees: fully-specified spawn specs with Node-shaped per-stream stdio dispositions (raw pipes, inherit, bounded tail-keep collection with spill files), the one credential scrub every harness spawner uses, offset-based incremental reads, tree-scoped signalling with SIGTERM→grace→SIGKILL escalation, and the cooperative dispose ladder. Command defaulting, shell semantics, deadlines, protocol framing, and presentation stay with consumers — the bash executors, the LSP host, and the ACP subagent backend. See the subprocess seam Agent Note.

Package	ctx key	Role
`subprocess` (`@deepseek-ai/dsh-subprocess`)	`ctx.subprocess`	The seam: abstract `SubprocessService.spawn(spec)`, the fully-explicit `SubprocessSpawnSpec` with per-stream stdio dispositions, `SubprocessHandle` (streams, offset-based readers, terminate/waitForExit/dispose), and the shared scrub + `DSH_*`/`CollectedOutput` vocabulary
`subprocess-local` (`@deepseek-ai/dsh-subprocess-local`)	—	The local implementation: detached process trees, per-disposition stream wiring, tail-keep truncation with bounded private spill files, the `DSH_*` merge order, tree signalling with escalation, the dispose ladder, and terminate-and-join disposal

The service owns process lifetime across consumer reloads; consumers own what a process means (a bash command, a future non-shell runner) and every default that shapes one.