diff --git a/packages/sdk-next/src/opencode.ts b/packages/sdk-next/src/opencode.ts
index 096b46d4b7..0c31592247 100644
--- a/packages/sdk-next/src/opencode.ts
+++ b/packages/sdk-next/src/opencode.ts
@@ -4,14 +4,30 @@ import { LayerNode } from "@opencode-ai/core/effect/layer-node"
 import { PermissionSaved } from "@opencode-ai/core/permission/saved"
 import { ApplicationTools } from "@opencode-ai/core/tool/application-tools"
 import { createEmbeddedRoutes } from "@opencode-ai/server/routes"
-import { Context, Effect, Layer, Scope } from "effect"
+import { ConfigProvider, Context, Effect, Layer, Scope } from "effect"
 import { FetchHttpClient, HttpRouter, HttpServer } from "effect/unstable/http"
 
-export const create = Effect.fn("OpenCode.create")(function* () {
+export interface Options {
+  /**
+   * Replaces the ConfigProvider this host's layers read while they are built,
+   * for example the OPENCODE_DB database placement. The default provider
+   * snapshots the process environment on first use, so per-host configuration
+   * must come through this seam rather than env mutation. Compose with
+   * ConfigProvider.orElse(ConfigProvider.fromEnv()) to keep environment
+   * fallback.
+   */
+  readonly configProvider?: ConfigProvider.ConfigProvider
+}
+
+export const create = Effect.fn("OpenCode.create")(function* (options?: Options) {
   const scope = yield* Scope.Scope
   const memoMap = yield* Layer.makeMemoMap
+  const withConfig = <A, E, R>(layer: Layer.Layer<A, E, R>) =>
+    options?.configProvider === undefined
+      ? layer
+      : layer.pipe(Layer.provide(ConfigProvider.layer(options.configProvider)))
   const context = yield* Layer.buildWithMemoMap(
-    AppNodeBuilder.build(LayerNode.group([ApplicationTools.node, PermissionSaved.node])),
+    withConfig(AppNodeBuilder.build(LayerNode.group([ApplicationTools.node, PermissionSaved.node]))),
     memoMap,
     scope,
   )
@@ -20,9 +36,11 @@ export const create = Effect.fn("OpenCode.create")(function* () {
   const web = yield* Effect.acquireRelease(
     Effect.sync(() =>
       HttpRouter.toWebHandler(
-        createEmbeddedRoutes().pipe(
-          HttpRouter.provideRequest(Layer.succeed(PermissionSaved.Service, permissions)),
-          Layer.provide(HttpServer.layerServices),
+        withConfig(
+          createEmbeddedRoutes().pipe(
+            HttpRouter.provideRequest(Layer.succeed(PermissionSaved.Service, permissions)),
+            Layer.provide(HttpServer.layerServices),
+          ),
         ),
         { disableLogger: true, memoMap },
       ),
@@ -47,3 +65,5 @@ export type Interface = Effect.Success<ReturnType<typeof create>>
 export class Service extends Context.Service<Service, Interface>()("@opencode-ai/sdk-next/OpenCode") {}
 
 export const layer = Layer.effect(Service, create())
+
+export const layerWith = (options: Options) => Layer.effect(Service, create(options))
diff --git a/packages/sdk-next/test/embedded.test.ts b/packages/sdk-next/test/embedded.test.ts
index 01cbec0e66..773801fb40 100644
--- a/packages/sdk-next/test/embedded.test.ts
+++ b/packages/sdk-next/test/embedded.test.ts
@@ -1,17 +1,15 @@
-import { afterAll, expect, test } from "bun:test"
+import { expect, test } from "bun:test"
 import { mkdtemp, rm } from "node:fs/promises"
 import { tmpdir } from "node:os"
 import { join } from "node:path"
-import { Deferred, Effect, Latch, Option, Schema, Stream } from "effect"
+import { ConfigProvider, Deferred, Effect, Latch, Option, Schema, Stream } from "effect"
 import type { OpenCodeEvent } from "../src"
 
-// The database layer resolves OPENCODE_DB through Effect Config, and the
-// default ConfigProvider snapshots the process environment on first use, so
-// database placement is process-wide. Point every embedded host in this file
-// at one shared temporary database before anything builds a runtime.
-const databaseDirectory = await mkdtemp(join(tmpdir(), "opencode-embedded-db-"))
-process.env.OPENCODE_DB = join(databaseDirectory, "opencode.sqlite")
-afterAll(() => rm(databaseDirectory, { recursive: true, force: true }))
+// The default ConfigProvider snapshots the process environment on first use,
+// so per-host database placement must come through the create() config seam
+// rather than env mutation.
+const databaseConfig = (directory: string) =>
+  ConfigProvider.fromUnknown({ OPENCODE_DB: join(directory, "opencode.sqlite") })
 
 test("embedded client uses the real router and handlers", async () => {
   const directory = await mkdtemp(join(tmpdir(), "opencode-embedded-"))
@@ -21,7 +19,7 @@ test("embedded client uses the real router and handlers", async () => {
 
   try {
     const program = Effect.gen(function* () {
-      const opencode = yield* OpenCode.create()
+      const opencode = yield* OpenCode.create({ configProvider: databaseConfig(directory) })
       yield* opencode.tools.register({
         embedded_tool: Tool.make({
           description: "Embedded test tool",
@@ -103,6 +101,8 @@ test("embedded client uses the real router and handlers", async () => {
       expect(missingMessage._tag).toBe("MessageNotFoundError")
     })
     await Effect.runPromise(Effect.scoped(program))
+    // The database materializes at the path this host's ConfigProvider chose.
+    expect(await Bun.file(join(directory, "opencode.sqlite")).exists()).toBe(true)
   } finally {
     await rm(directory, { recursive: true, force: true })
   }
@@ -115,7 +115,7 @@ test("Location-owned runner events reach the ready global client", async () => {
 
   try {
     const program = Effect.gen(function* () {
-      const opencode = yield* OpenCode.create()
+      const opencode = yield* OpenCode.create({ configProvider: databaseConfig(directory) })
       const connected = yield* Latch.make(false)
       const prompted = yield* Deferred.make<OpenCodeEvent>()
       yield* opencode.events.subscribe().pipe(
@@ -151,8 +151,8 @@ test("independent embedded hosts do not share live notifications", async () => {
 
   try {
     const program = Effect.gen(function* () {
-      const first = yield* OpenCode.create()
-      const second = yield* OpenCode.create()
+      const first = yield* OpenCode.create({ configProvider: databaseConfig(directory) })
+      const second = yield* OpenCode.create({ configProvider: databaseConfig(directory) })
       const firstReady = yield* Latch.make(false)
       const secondReady = yield* Latch.make(false)
       const firstEvent = yield* Latch.make(false)
@@ -197,7 +197,7 @@ test("embedded client is available as a Layer service", async () => {
           id: sessionID,
           location: Location.Ref.make({ directory: AbsolutePath.make(directory) }),
         })
-      }).pipe(Effect.provide(OpenCode.layer), Effect.scoped),
+      }).pipe(Effect.provide(OpenCode.layerWith({ configProvider: databaseConfig(directory) })), Effect.scoped),
     )
 
     expect(created.id).toBe(sessionID)