createEmbeddedRoutes accepts runtime-profile service replacements, and the
embedded SDK exposes them through EmbedOptions: overrides applied after the
standard set, plus an opt-in boot-time resume of Sessions whose execution
claim was never released, for runtimes that die without teardown.
@opencode-ai/sdk-next/workerd composes the workerd profile
(ServerWorkerd.serverOptions + replacements) with the embedded SDK, so a
Durable Object host gets the same typed client and event streams as any other
sdk-next consumer, over Durable Object SQLite, with no network hop.
Health reports pid 0 where the runtime has no OS process identity, and the
drizzle session delegates to the client's native withTransaction when the
client rejects BEGIN/SAVEPOINT (Durable Object SQLite). Node platform modules
are deep-imported so the barrel's eager undici and node:sqlite side imports
never load.
ServerWorkerd.create builds the fetch handler for a Durable Object's fetch(),
with every intentionally-local service replaced: the database runs on the
injected DO SQLite, plugin discovery is precompiled-only, MCP is remote-only,
Snapshot and Vcs degrade to empty results, and Shell/FileSystem/Pty fail with
a clear defect until a remote sandbox backs them.
Threading it through needs one seam: createRoutes and ServerFetch.make take
runtime-profile replacements applied after the standard set, so later entries
win. script/workerd-probe.ts pins that the graph bundles under the workerd
condition without bun builtins.
Kit Langton