In-place port of dsh-workflow-vm from the in-process node:vm execution to one worker thread per run (the workflow-workerthread engine of PR #215, adopted as THE engine): the script's vm context moves inside the worker, agent() bridges to ctx.subagents over the message port (host.ts/protocol.ts/session.ts/worker.ts are new; runtime.ts loses the abandon channel — the host's grace timer force-settles and TERMINATES instead), start() pre-parses the body host-side to keep the seam's synchronous SCRIPT_PARSE throw, and a ready→go handshake keeps a run cancelled before start from ever executing the body. start() no longer blocks the host, termination is real, and the value boundary is serialization by construction. The package keeps its name until the follow-up rename commit; scripts see the identical hook surface, and the seam-contract tests hardened ahead of this swap pass unchanged. The run and child-RPC surfaces are class-shaped rather than literal bundles: WorkerRun IMPLEMENTS the seam's WorkflowRun (id/meta are its own clone, separate from event payloads') and start() returns the instance directly — interface parity with the seam is compiler-checked; worker-side, ChildRpcBridge (implements ChildPort; callId allocation + pending book-keeping settled by onChild* entry points) and RpcChildHandle (every member an RPC keyed by its callId) carry names in stacks. ChildPort's method is startAgent — it names what it starts, matching the script-side agent() hook and the agentsStarted / workflow/agent-* vocabulary; the Child* type names deliberately stay (the worker side is cordis- and subagent-free; these are reduced JSON projections, not the seam's types). Review findings from the reference PR are folded in rather than re-introduced: - cancel() drives BOTH child-cancel channels host-side: the request signal aborts AND each registered child's explicit cancel() is called — a worker wedged in a synchronous spin cannot relay its own ChildCancel RPCs (regression: cancel-only provider + wedged worker). - All host warn paths render through the total renderThrown; a child dispose() rejecting a value whose coercion throws still acks ChildDisposed instead of wedging the script's finally (regression). - built-worker.e2e.ts is wired into builtBinSmokeGate and the AGENTS.md CI sequence — the built lib/worker.js resolution contract now runs in an automated gate. - workflow/end payload pinned on the worker-death path (with the cancelled and grace-force-settle pins riding the ported spec). - Real-Worker scripted timing budgets widened (50-300ms → 150-1000ms) for starved CI hosts. Workspace plumbing: the "./worker" subpath export sanctions the second runtime bundle (check-workspace-constraints), tsdown builds two single-entry passes, tsx becomes a devDependency for the unbuilt worker spawn.
Packages
Harness packages, all under the @deepseek-ai/dsh-* scope. Each package is a Cordis plugin (microkernel-style): it exports either a default Service subclass or a functional plugin, declares its ctx key/events through declaration merging, and exposes extension points through ctx.effect(), ctx.on(), and ctx.waterfall(). Authoring conventions: AGENTS.md (subtree) and the root AGENTS.md § Conventions.
Hierarchy
Packages are grouped by modular role at packages/<group>/<pkg>/. The group directory is a pure container (no package.json of its own); the package name stays @deepseek-ai/dsh-<pkg> regardless of group. Each group README is the canonical per-package map — package roles, ctx keys, and the product-vs-support split live there, next to the code.
| Group | Role | Release expectation |
|---|---|---|
core/ |
Product API spine: session, system-prompt, tools, agent, and the concrete loop | Product — stable surface |
llm/ |
LLM capability family: the abstract service + provider adapters | Product — stable surface |
bash/ |
Bash capability family: the executor seam, a local impl, and the model-facing tool | Product — stable surface |
fs/ |
Filesystem capability family: the abstract seam, a local impl, and the model-facing file tools | Product — stable surface |
compact/ |
Compaction capability family: the abstract seam + a basic backend (tool deferred) | Product — stable surface |
subagent/ |
Subagent capability family: the provider-registry seam and the model-facing delegation tool | Product — stable surface |
workflow/ |
Workflow capability family: the script-engine seam, the node:vm engine, and the model-facing workflow tool |
Product — stable surface |
web/ |
Web capability family: the abstract seam, search/fetch provider impls, and the model-facing web tools | Product — stable surface |
todo/ |
Todo/planning family: the model-facing todo_write tool (whole-list task tracking on the session log) |
Product — stable surface |
hooks/ |
Hook bridges + the shared Claude Code / Codex wire-protocol library | Product — stable surface |
session-persistence/ |
Persistence capability family: the seam + JSONL/SQLite backends | Product — stable surface |
ui/ |
Editor/client integration surfaces (the ACP bridge) + the app packages | Product — stable surface |
support/ |
Dev/test/example infrastructure (invariants, replay adapter, subagent mock) | Support — lower compatibility expectations |
util/ |
Low-level zero-dependency utilities shared across groups (the Branded<B> primitive) |
Support — small, stable, harness-dep-free |
The split is the point: a package's group says whether it is part of the product API or support/test/example infrastructure, so release and removal decisions do not treat every package as an equal public contract. New packages join an existing group; adding a new top-level group is a deliberate act (extend the group READMEs and this table).
Dependencies
The inter-package dependency graph is generated: docs/module-graph.md (pnpm run gen-module-graph, freshness-gated in CI).
The rule it must obey: extension plugins depend on interfaces, never on the concrete loop. dsh-agent-loop is swappable — UI/hook/tool plugins keep working against the dsh-agent vocabulary if the loop is replaced. The sanctioned exception is a composition/bundle package like dsh-agent-core, whose whole job is to assemble the concrete spine: it depends on dsh-agent-loop (and the other concrete spine plugins) on purpose. The rule constrains plugins that EXTEND the system, not the bundle that COMPOSES it — swapping the loop means shipping a different bundle, not rewiring every extension. A swappable capability splits into interface / implementation / consumer packages (the bash trio is the template — see capability seams).
Each package has its own README.md with purpose, service API, events, extension points, and deliberate non-goals (TODOs).