CodeNomad/dev-docs/technical-implementation.md

Technical Implementation

OpenCode Dependency

Server and UI use the same reviewed experimental @opencode-ai/client release. Import the generated Promise client from @opencode-ai/client. Runtime startup probes the selected CLI and discovery/ensure require the exact server dependency version. Every upgrade must review OpenCode release notes, current documentation, installed declarations, and proxy/API parity.

Do not add @opencode-ai/sdk, old { data, error } SDK wrappers, createOpencodeClient(), or a packages/opencode-plugin package. Verify method signatures in node_modules/@opencode-ai/client/dist/promise/.

Server Integration

OpenCodeSharedService is the sole service adapter. Production uses Service.discover and Service.headers, then a custom launcher with lease and process-identity proof. Proven host shutdown delegates to native Service.stop; WSL uses native authenticated health stop to avoid the client's Windows PID fallback.

Startup and shutdown are serialized by filesystem leases. Each CodeNomad process proves its own PID/start identity and launch signature; service proof contains the registration contents, endpoint credentials, daemon PID/start identity, and host/WSL namespace. On exit, an owner transfers that proof to an elected live peer and releases its lease; a replacement can also inherit matching proof from a stale peer under the lifecycle lock. The final process stops only after all peers are proven stale/absent and the registration, endpoint, process identity, and launch signature still match; uncertainty retains the lease and leaks safely rather than signaling a PID.

The V2 service database is fixed at ~/.local/share/opencode2/opencode.db; V1 and V2 schemas must never share a database. The complete environment is part of the launch signature and takes effect on service start/restart, not on an already-running daemon.

Workspace creation passes a native location:

await client.location.get({ location: { directory } })

WorkspaceManager records the returned directory/workspace ID. After the final logical owner is removed, eviction is queued and is sent only during proven final shared-service shutdown, after cross-process peer and daemon identity checks.

UI Integration

packages/ui/src/lib/sdk-manager.ts constructs clients with OpenCode.make() at /workspaces/:id/instance/. Use getRootClient(instanceId) from packages/ui/src/stores/opencode-client.ts; pass native directory/location inputs when required.

Session actions use native APIs directly:

await client.session.prompt({ sessionID, text, files })
await client.session.shell({ sessionID, command })
await client.session.instructions.entry.put({ sessionID, key, value })

Shell mode and conversation instructions are upstream features and remain separate from native V2 PTYs. None requires a CodeNomad plugin.

Native PTYs are location-scoped and listed in the Status panel. packages/ui/src/stores/pty-store.ts refreshes the list on native PTY events and reconnect, exposes native metadata, and supports title updates and removal. The proxy verifies PTY cwd ownership before ID-scoped operations. Current installed declarations have no PTY output/read/stream API and no separate stop endpoint: output is not displayed, and removing a running PTY is the only native stop action.

Routing And Security

• CodeNomad operations: packages/ui/src/lib/api-client.ts -> /api/*.
• OpenCode operations: generated client -> /workspaces/:id/instance/api/*.
• Browser events: GET /api/events; heartbeat response: POST /api/client-connections/pong.
• The proxy exposes only an explicit method/path allowlist, checks client-provided directories and prompt files, defaults safe requests to the workspace location, and verifies session ownership before forwarding. New OpenCode routes are unavailable until reviewed and allowlisted.

Never trust a browser-supplied worktree path. Resolve workspace/worktree ownership server-side.

CodeNomad-Owned Mutations

Git status/diff and mutations remain CodeNomad APIs. Stage, unstage and commit execute validated Git commands in packages/server/src/workspaces/git-mutations.ts; the UI calls /api/workspaces/:id/worktrees/:slug/git-*.

Yolo also remains CodeNomad-owned. AutoAcceptManager persists policy state, observes native permission events, replies with client.permission.reply, and publishes yolo.stateChanged/yolo.autoAccepted over /api/events.

Events

InstanceEventBridge consumes the one shared client.event.subscribe() iterable. It maps location-scoped events to workspace IDs and publishes instance.event through the CodeNomad EventBus. This stream is volatile: reconnection does not replay a guaranteed history, so UI stores refetch sessions and pending requests and other consumers must re-read authoritative file/config state.

Use current protocol names. Session events include session.created, session.renamed, session.moved, session.status, session.idle, session.execution.*, session.compaction.*, session.text.*, session.reasoning.*, and session.tool.*; PTY refresh events include pty.created, pty.updated, pty.exited, and pty.deleted; file and config invalidations are filesystem.changed and config.updated.

Current Structure

packages/server/src/
  server/routes/            CodeNomad /api routes
  workspaces/manager.ts     workspace/location ownership
  workspaces/opencode-service.ts
  workspaces/instance-events.ts
  workspaces/git-status.ts
  workspaces/git-mutations.ts
  permissions/              Yolo and permission policy

packages/ui/src/
  lib/api-client.ts         CodeNomad API and /api/events
  lib/sdk-manager.ts        native OpenCode Promise clients
  stores/opencode-client.ts root client authority
  stores/session-api.ts     session queries/lifecycle
  stores/session-actions.ts prompt, Shell, instructions
  stores/pty-store.ts       location-scoped native PTY state/actions

Deleted packages/opencode-plugin, server plugin/background-process, and per-workspace runtime files are not architectural extension points and must not be restored.

Validation

• Run root typecheck or the relevant server/UI workspace typecheck.
• Run focused tests for service lifecycle, instance proxy, event bridge, Git mutations, or Yolo when changing those boundaries.
• Update server API types and UI consumers together.