diff --git a/packages/opencode/src/effect/service-use.ts b/packages/core/src/effect/service-use.ts
similarity index 85%
rename from packages/opencode/src/effect/service-use.ts
rename to packages/core/src/effect/service-use.ts
index a93cdecbb15..89d9acf98ea 100644
--- a/packages/opencode/src/effect/service-use.ts
+++ b/packages/core/src/effect/service-use.ts
@@ -15,6 +15,7 @@ type ServiceUse<Identifier, Shape> = {
 }
 
 export const serviceUse = <Identifier, Shape>(tag: Context.Service<Identifier, Shape>) => {
+  const cache = new Map<string, (...args: unknown[]) => Effect.Effect<unknown, unknown, unknown>>()
   // This is the only dynamic boundary: TypeScript knows the accessor shape,
   // but Proxy property names are runtime values.
   const access = new Proxy(
@@ -22,7 +23,9 @@ export const serviceUse = <Identifier, Shape>(tag: Context.Service<Identifier, S
     {
       get: (_, key) => {
         if (typeof key !== "string") return undefined
-        return (...args: unknown[]) =>
+        const cached = cache.get(key)
+        if (cached) return cached
+        const accessor = (...args: unknown[]) =>
           tag.use((service) => {
             // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- Proxy keys are checked at runtime.
             const method = service[key as keyof Shape]
@@ -30,6 +33,8 @@ export const serviceUse = <Identifier, Shape>(tag: Context.Service<Identifier, S
             // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- ServiceUse exposes only Effect-returning methods.
             return (method as (...args: unknown[]) => Effect.Effect<unknown, unknown, unknown>)(...args)
           })
+        cache.set(key, accessor)
+        return accessor
       },
     },
   )
diff --git a/packages/core/src/filesystem.ts b/packages/core/src/filesystem.ts
index 06170beed9d..d4bfe6dba43 100644
--- a/packages/core/src/filesystem.ts
+++ b/packages/core/src/filesystem.ts
@@ -3,46 +3,10 @@ import { dirname, join, relative, resolve as pathResolve } from "path"
 import { realpathSync } from "fs"
 import * as NFS from "fs/promises"
 import { lookup } from "mime-types"
-import { Effect, FileSystem, Layer, Schema, Context } from "effect"
+import { Context, Effect, FileSystem, Layer, Schema } from "effect"
 import type { PlatformError } from "effect/PlatformError"
 import { Glob } from "./util/glob"
-
-type EffectMethod = (...args: ReadonlyArray<never>) => Effect.Effect<unknown, unknown, unknown>
-
-type ServiceUse<Identifier, Shape> = {
-  readonly [Key in keyof Shape as Shape[Key] extends EffectMethod ? Key : never]: Shape[Key] extends (
-    ...args: infer Args
-  ) => infer Return
-    ? Args extends ReadonlyArray<unknown>
-      ? Return extends Effect.Effect<infer A, infer E, infer R>
-        ? (...args: Args) => Effect.Effect<A, E, R | Identifier>
-        : never
-      : never
-    : never
-}
-
-const serviceUse = <Identifier, Shape>(tag: Context.Service<Identifier, Shape>) => {
-  // This is the only dynamic boundary: TypeScript knows the accessor shape,
-  // but Proxy property names are runtime values.
-  const access = new Proxy(
-    {},
-    {
-      get: (_, key) => {
-        if (typeof key !== "string") return undefined
-        return (...args: unknown[]) =>
-          tag.use((service) => {
-            // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- Proxy keys are checked at runtime.
-            const method = service[key as keyof Shape]
-            if (typeof method !== "function") return Effect.die(new Error(`Service method not found: ${key}`))
-            // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- ServiceUse exposes only Effect-returning methods.
-            return (method as (...args: unknown[]) => Effect.Effect<unknown, unknown, unknown>)(...args)
-          })
-      },
-    },
-  )
-  // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- Proxy implements the mapped accessor surface lazily.
-  return access as ServiceUse<Identifier, Shape>
-}
+import { serviceUse } from "./effect/service-use"
 
 export namespace AppFileSystem {
   export class FileSystemError extends Schema.TaggedErrorClass<FileSystemError>()("FileSystemError", {
diff --git a/packages/opencode/src/account/account.ts b/packages/opencode/src/account/account.ts
index dcff82664b1..2d855e0e952 100644
--- a/packages/opencode/src/account/account.ts
+++ b/packages/opencode/src/account/account.ts
@@ -1,5 +1,5 @@
 import { Cache, Clock, Duration, Effect, Layer, Option, Schema, SchemaGetter, Context } from "effect"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import {
   FetchHttpClient,
   HttpClient,
diff --git a/packages/opencode/src/account/repo.ts b/packages/opencode/src/account/repo.ts
index a5291e8283c..052f1cbd65a 100644
--- a/packages/opencode/src/account/repo.ts
+++ b/packages/opencode/src/account/repo.ts
@@ -1,5 +1,5 @@
 import { eq } from "drizzle-orm"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Effect, Layer, Option, Schema, Context } from "effect"
 
 import { Database } from "@/storage/db"
diff --git a/packages/opencode/src/agent/agent.ts b/packages/opencode/src/agent/agent.ts
index f7e2c134a37..064a59f59ed 100644
--- a/packages/opencode/src/agent/agent.ts
+++ b/packages/opencode/src/agent/agent.ts
@@ -1,5 +1,5 @@
 import { Config } from "@/config/config"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Provider } from "@/provider/provider"
 import { ModelID, ProviderID } from "../provider/schema"
 import { generateObject, streamObject, type ModelMessage } from "ai"
diff --git a/packages/opencode/src/bus/index.ts b/packages/opencode/src/bus/index.ts
index b5f4320bda6..73ec18d73b1 100644
--- a/packages/opencode/src/bus/index.ts
+++ b/packages/opencode/src/bus/index.ts
@@ -5,7 +5,7 @@ import { BusEvent } from "./bus-event"
 import { GlobalBus } from "./global"
 import { InstanceState } from "@/effect/instance-state"
 import { makeRuntime } from "@/effect/run-service"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Identifier } from "@/id/id"
 import type { InstanceContext } from "@/project/instance-context"
 import { InstanceRef } from "@/effect/instance-ref"
diff --git a/packages/opencode/src/config/config.ts b/packages/opencode/src/config/config.ts
index 349b7e6a074..307b02ca4d9 100644
--- a/packages/opencode/src/config/config.ts
+++ b/packages/opencode/src/config/config.ts
@@ -1,5 +1,5 @@
 import * as Log from "@opencode-ai/core/util/log"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import path from "path"
 import { pathToFileURL } from "url"
 import os from "os"
diff --git a/packages/opencode/src/control-plane/workspace.ts b/packages/opencode/src/control-plane/workspace.ts
index d1b4b12f635..9f44d22334c 100644
--- a/packages/opencode/src/control-plane/workspace.ts
+++ b/packages/opencode/src/control-plane/workspace.ts
@@ -1,5 +1,5 @@
 import { Context, Effect, FiberMap, Iterable, Layer, Schema, Stream } from "effect"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { FetchHttpClient, HttpBody, HttpClient, HttpClientError, HttpClientRequest } from "effect/unstable/http"
 import { Database } from "@/storage/db"
 import { asc } from "drizzle-orm"
diff --git a/packages/opencode/src/env/index.ts b/packages/opencode/src/env/index.ts
index efdfd0ac01a..89ccf7d0fd3 100644
--- a/packages/opencode/src/env/index.ts
+++ b/packages/opencode/src/env/index.ts
@@ -1,5 +1,5 @@
 import { Context, Effect, Layer } from "effect"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { InstanceState } from "@/effect/instance-state"
 
 type State = Record<string, string | undefined>
diff --git a/packages/opencode/src/file/index.ts b/packages/opencode/src/file/index.ts
index 0f17ed2792b..0992289fe29 100644
--- a/packages/opencode/src/file/index.ts
+++ b/packages/opencode/src/file/index.ts
@@ -1,5 +1,5 @@
 import { BusEvent } from "@/bus/bus-event"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { InstanceState } from "@/effect/instance-state"
 
 import { AppFileSystem } from "@opencode-ai/core/filesystem"
diff --git a/packages/opencode/src/file/ripgrep.ts b/packages/opencode/src/file/ripgrep.ts
index c1a636782bb..8b3d5cf174a 100644
--- a/packages/opencode/src/file/ripgrep.ts
+++ b/packages/opencode/src/file/ripgrep.ts
@@ -1,5 +1,5 @@
 import path from "path"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { AppFileSystem } from "@opencode-ai/core/filesystem"
 import { Cause, Context, Effect, Fiber, Layer, Queue, Schema, Stream } from "effect"
 import type { PlatformError } from "effect/PlatformError"
diff --git a/packages/opencode/src/format/index.ts b/packages/opencode/src/format/index.ts
index eb55b0713b8..6d0311f6fa7 100644
--- a/packages/opencode/src/format/index.ts
+++ b/packages/opencode/src/format/index.ts
@@ -1,5 +1,5 @@
 import { Effect, Layer, Context, Schema } from "effect"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { ChildProcess } from "effect/unstable/process"
 import { AppProcess } from "@opencode-ai/core/process"
 import { InstanceState } from "@/effect/instance-state"
diff --git a/packages/opencode/src/installation/index.ts b/packages/opencode/src/installation/index.ts
index d96924a2a0b..1f8dc116b18 100644
--- a/packages/opencode/src/installation/index.ts
+++ b/packages/opencode/src/installation/index.ts
@@ -1,5 +1,5 @@
 import { Effect, Layer, Schema, Context, Stream } from "effect"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { FetchHttpClient, HttpClient, HttpClientRequest, HttpClientResponse } from "effect/unstable/http"
 import { withTransientReadRetry } from "@/util/effect-http-client"
 import { errorMessage } from "@/util/error"
diff --git a/packages/opencode/src/mcp/auth.ts b/packages/opencode/src/mcp/auth.ts
index d7406e5192d..adddea0b35a 100644
--- a/packages/opencode/src/mcp/auth.ts
+++ b/packages/opencode/src/mcp/auth.ts
@@ -1,5 +1,5 @@
 import path from "path"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Global } from "@opencode-ai/core/global"
 import { Effect, Layer, Context, Option, Schema } from "effect"
 import { AppFileSystem } from "@opencode-ai/core/filesystem"
diff --git a/packages/opencode/src/mcp/index.ts b/packages/opencode/src/mcp/index.ts
index 85985876e72..efd72c0c1f7 100644
--- a/packages/opencode/src/mcp/index.ts
+++ b/packages/opencode/src/mcp/index.ts
@@ -1,5 +1,5 @@
 import { dynamicTool, type Tool, jsonSchema, type JSONSchema7 } from "ai"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Client } from "@modelcontextprotocol/sdk/client/index.js"
 import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js"
 import { SSEClientTransport } from "@modelcontextprotocol/sdk/client/sse.js"
diff --git a/packages/opencode/src/project/instance-store.ts b/packages/opencode/src/project/instance-store.ts
index 8c847fd9934..1f513fb1b49 100644
--- a/packages/opencode/src/project/instance-store.ts
+++ b/packages/opencode/src/project/instance-store.ts
@@ -1,5 +1,5 @@
 import { GlobalBus } from "@/bus/global"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { WorkspaceContext } from "@/control-plane/workspace-context"
 import { InstanceRef } from "@/effect/instance-ref"
 import { disposeInstance as runDisposers } from "@/effect/instance-registry"
diff --git a/packages/opencode/src/project/project.ts b/packages/opencode/src/project/project.ts
index a12c2cde1f8..4b4f2cdf584 100644
--- a/packages/opencode/src/project/project.ts
+++ b/packages/opencode/src/project/project.ts
@@ -20,7 +20,7 @@ import { AppProcess } from "@opencode-ai/core/process"
 import { Project as ProjectV2 } from "@opencode-ai/core/project"
 import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
 import { AbsolutePath, NonNegativeInt, optionalOmitUndefined } from "@opencode-ai/core/schema"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 
 const log = Log.create({ service: "project" })
diff --git a/packages/opencode/src/provider/auth.ts b/packages/opencode/src/provider/auth.ts
index 214ab3bd997..a304fec540b 100644
--- a/packages/opencode/src/provider/auth.ts
+++ b/packages/opencode/src/provider/auth.ts
@@ -1,5 +1,5 @@
 import type { AuthOAuthResult, Hooks } from "@opencode-ai/plugin"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Auth } from "@/auth"
 import { InstanceState } from "@/effect/instance-state"
 import { optionalOmitUndefined } from "@opencode-ai/core/schema"
diff --git a/packages/opencode/src/provider/provider.ts b/packages/opencode/src/provider/provider.ts
index 2140bea4df9..496a2f6d2d3 100644
--- a/packages/opencode/src/provider/provider.ts
+++ b/packages/opencode/src/provider/provider.ts
@@ -7,7 +7,7 @@ import * as Log from "@opencode-ai/core/util/log"
 import { Npm } from "@opencode-ai/core/npm"
 import { Hash } from "@opencode-ai/core/util/hash"
 import { Plugin } from "../plugin"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { type LanguageModelV3 } from "@ai-sdk/provider"
 import * as ModelsDev from "@opencode-ai/core/models-dev"
 import { Auth } from "../auth"
diff --git a/packages/opencode/src/session/compaction.ts b/packages/opencode/src/session/compaction.ts
index ef007fe74d3..4f87edf64a5 100644
--- a/packages/opencode/src/session/compaction.ts
+++ b/packages/opencode/src/session/compaction.ts
@@ -16,7 +16,7 @@ import { Effect, Layer, Context, Schema } from "effect"
 import * as DateTime from "effect/DateTime"
 import { InstanceState } from "@/effect/instance-state"
 import { isOverflow as overflow, usable } from "./overflow"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { EventV2Bridge } from "@/event-v2-bridge"
 import { SessionEvent } from "@opencode-ai/core/session-event"
diff --git a/packages/opencode/src/session/llm.ts b/packages/opencode/src/session/llm.ts
index ec87bfc4469..ea2efc99d00 100644
--- a/packages/opencode/src/session/llm.ts
+++ b/packages/opencode/src/session/llm.ts
@@ -1,5 +1,5 @@
 import { Provider } from "@/provider/provider"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import * as Log from "@opencode-ai/core/util/log"
 import { Context, Effect, Layer } from "effect"
 import * as Stream from "effect/Stream"
diff --git a/packages/opencode/src/session/session.ts b/packages/opencode/src/session/session.ts
index 0131d443893..f75ac910d40 100644
--- a/packages/opencode/src/session/session.ts
+++ b/packages/opencode/src/session/session.ts
@@ -1,5 +1,5 @@
 import { Slug } from "@opencode-ai/core/util/slug"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import path from "path"
 import { BackgroundJob } from "@/background/job"
 import { BusEvent } from "@/bus/bus-event"
diff --git a/packages/opencode/src/share/share-next.ts b/packages/opencode/src/share/share-next.ts
index 98d5c822550..ab2d9d151d6 100644
--- a/packages/opencode/src/share/share-next.ts
+++ b/packages/opencode/src/share/share-next.ts
@@ -1,5 +1,5 @@
 import type * as SDK from "@opencode-ai/sdk/v2"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Effect, Exit, Layer, Option, Schema, Scope, Context, Stream } from "effect"
 import { FetchHttpClient, HttpClient, HttpClientRequest, HttpClientResponse } from "effect/unstable/http"
 import { Account } from "@/account/account"
diff --git a/packages/opencode/src/sync/index.ts b/packages/opencode/src/sync/index.ts
index a8858255f22..8573636615d 100644
--- a/packages/opencode/src/sync/index.ts
+++ b/packages/opencode/src/sync/index.ts
@@ -12,7 +12,7 @@ import { EventID } from "./schema"
 import { Context, Effect, Layer, Schema as EffectSchema } from "effect"
 import type { DeepMutable } from "@opencode-ai/core/schema"
 import { EventV2 } from "@opencode-ai/core/event"
-import { serviceUse } from "@/effect/service-use"
+import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { InstanceState } from "@/effect/instance-state"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { EffectBridge } from "@/effect/bridge"
diff --git a/packages/opencode/test/config/config.test.ts b/packages/opencode/test/config/config.test.ts
index f0778a6a54b..49b7643d7bc 100644
--- a/packages/opencode/test/config/config.test.ts
+++ b/packages/opencode/test/config/config.test.ts
@@ -26,11 +26,6 @@ import {
 import { InstanceRuntime } from "@/project/instance-runtime"
 import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
 import { testEffect } from "../lib/effect"
-
-/** Infra layer that provides FileSystem, Path, ChildProcessSpawner for test fixtures */
-const infra = CrossSpawnSpawner.defaultLayer.pipe(
-  Layer.provideMerge(Layer.mergeAll(NodeFileSystem.layer, NodePath.layer)),
-)
 import path from "path"
 import fs from "fs/promises"
 import { pathToFileURL } from "url"
@@ -42,6 +37,11 @@ import { AccountTest } from "../fake/account"
 import { AuthTest } from "../fake/auth"
 import { NpmTest } from "../fake/npm"
 
+/** Infra layer that provides FileSystem, Path, ChildProcessSpawner for test fixtures */
+const infra = CrossSpawnSpawner.defaultLayer.pipe(
+  Layer.provideMerge(Layer.mergeAll(NodeFileSystem.layer, NodePath.layer)),
+)
+
 const testFlock = EffectFlock.defaultLayer
 
 const unexpectedHttp = HttpClient.make((request) =>
@@ -148,28 +148,29 @@ async function writeConfig(dir: string, config: object, name = "opencode.json")
 }
 
 const writeConfigEffect = (dir: string, config: object, name = "opencode.json") =>
-  AppFileSystem.use.writeFileString(path.join(dir, name), JSON.stringify(config))
+  AppFileSystem.use.writeWithDirs(path.join(dir, name), JSON.stringify(config))
 
-const project = {
-  dir: (relative: string) =>
-    TestInstance.use((test) => AppFileSystem.use.ensureDir(path.join(test.directory, relative))),
-  file: (relative: string, content: string) =>
-    TestInstance.use((test) => AppFileSystem.use.writeWithDirs(path.join(test.directory, relative), content)),
-}
+const withInstanceDir = <A, E, R>(dir: string, effect: Effect.Effect<A, E, R>) =>
+  effect.pipe(
+    Effect.provideService(TestInstance, { directory: dir }),
+    provideInstanceEffect(dir),
+    Effect.provide(testInstanceStoreLayer),
+    Effect.provide(CrossSpawnSpawner.defaultLayer),
+  )
 
 const withGlobalConfigDir = <A, E, R>(dir: string, effect: Effect.Effect<A, E, R>) =>
   Effect.acquireUseRelease(
     Effect.gen(function* () {
       const previous = Global.Path.config
       ;(Global.Path as { config: string }).config = dir
-      yield* clearEffect(true)
+      yield* clearEffect()
       return previous
     }),
     () => effect,
     (previous) =>
       Effect.gen(function* () {
         ;(Global.Path as { config: string }).config = previous
-        yield* clearEffect(true)
+        yield* clearEffect()
       }),
   )
 
@@ -190,17 +191,17 @@ const withConfigTree = <A, E, R>(
   Effect.gen(function* () {
     const root = yield* tmpdirScoped()
     const directory = path.join(root, "project")
-    const local = path.join(directory, ".opencode")
-    yield* AppFileSystem.use.ensureDir(local)
-    if (input.global) yield* writeConfigEffect(root, schemaConfig(input.global))
-    if (input.project) yield* writeConfigEffect(directory, schemaConfig(input.project))
-    if (input.local) yield* writeConfigEffect(local, schemaConfig(input.local))
-    return yield* effect.pipe(
-      Effect.provideService(TestInstance, { directory }),
-      provideInstanceEffect(directory),
-      Effect.provide(testInstanceStoreLayer),
-      Effect.provide(CrossSpawnSpawner.defaultLayer),
+    yield* Effect.all(
+      [
+        input.global ? writeConfigEffect(root, schemaConfig(input.global)) : undefined,
+        input.project ? writeConfigEffect(directory, schemaConfig(input.project)) : undefined,
+        input.local ? writeConfigEffect(path.join(directory, ".opencode"), schemaConfig(input.local)) : undefined,
+      ].filter(
+        (effect): effect is Effect.Effect<void, AppFileSystem.Error, AppFileSystem.Service> => effect !== undefined,
+      ),
+      { concurrency: "unbounded" },
     )
+    return yield* withInstanceDir(directory, effect)
   })
 
 const wellKnown = (input: {
@@ -705,7 +706,6 @@ it.instance("migrates mode field to agent field", () =>
 it.instance("loads config from .opencode directory", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
-    yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "agent"))
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, ".opencode", "agent", "test.md"),
       `---
@@ -728,7 +728,6 @@ Test agent prompt`,
 it.instance("agent markdown permission config preserves user key order", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
-    yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "agent"))
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, ".opencode", "agent", "ordered.md"),
       `---
@@ -748,7 +747,6 @@ Ordered permissions`,
 it.instance("loads agents from .opencode/agents (plural)", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
-    yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "agents", "nested"))
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, ".opencode", "agents", "helper.md"),
       `---
@@ -788,7 +786,6 @@ Nested agent prompt`,
 it.instance("loads commands from .opencode/command (singular)", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
-    yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "command", "nested"))
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, ".opencode", "command", "hello.md"),
       `---
@@ -822,7 +819,6 @@ Nested command template`,
 it.instance("loads commands from .opencode/commands (plural)", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
-    yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "commands", "nested"))
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, ".opencode", "commands", "hello.md"),
       `---
@@ -912,7 +908,6 @@ it.instance("resolves scoped npm plugins in config", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
     const pluginDir = path.join(test.directory, "node_modules", "@scope", "plugin")
-    yield* AppFileSystem.use.ensureDir(pluginDir)
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, "package.json"),
       JSON.stringify({ name: "config-fixture", version: "1.0.0", type: "module" }, null, 2),
@@ -960,7 +955,6 @@ it.effect("merges plugin arrays from global and local configs", () =>
 it.instance("does not error when only custom agent is a subagent", () =>
   Effect.gen(function* () {
     const test = yield* TestInstance
-    yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "agent"))
     yield* AppFileSystem.use.writeWithDirs(
       path.join(test.directory, ".opencode", "agent", "helper.md"),
       `---
@@ -1671,8 +1665,11 @@ describe("deduplicatePluginOrigins", () => {
     withConfigTree(
       { global: { plugin: ["my-plugin@1.0.0"] } },
       Effect.gen(function* () {
-        yield* project.dir(".opencode/plugin")
-        yield* project.file(".opencode/plugin/my-plugin.js", "export default {}")
+        const test = yield* TestInstance
+        yield* AppFileSystem.use.writeWithDirs(
+          path.join(test.directory, ".opencode", "plugin", "my-plugin.js"),
+          "export default {}",
+        )
 
         const plugins = (yield* Config.use.get()).plugin ?? []
         expect(plugins.some((p) => ConfigPlugin.pluginSpecifier(p) === "my-plugin@1.0.0")).toBe(true)
@@ -1704,7 +1701,6 @@ describe("OPENCODE_DISABLE_PROJECT_CONFIG", () => {
       "true",
       Effect.gen(function* () {
         const test = yield* TestInstance
-        yield* AppFileSystem.use.ensureDir(path.join(test.directory, ".opencode", "command"))
         yield* AppFileSystem.use.writeWithDirs(
           path.join(test.directory, ".opencode", "command", "test-cmd.md"),
           "# Test Command\nThis is a test command.",