fix: extension loading in Bun binary (#681)

- Remove loader exports from index.ts to break circular dependency
- Static import of index.js in loader.ts for virtualModules
- Add @mariozechner/pi-agent-core to virtualModules
- Update @mariozechner/jiti to 2.6.5 (bundles babel for Bun binary)
- Update SDK docs to use correct extension terminology

package-lock.json

@@ -13,6 +13,7 @@
 				"packages/coding-agent/examples/extensions/with-deps"
 			],
 			"dependencies": {
+				"@mariozechner/jiti": "^2.6.5",
 				"@mariozechner/pi-coding-agent": "^0.30.2",
 				"get-east-asian-width": "^1.4.0"
 			},
@@ -1781,9 +1782,9 @@
 			}
 		},
 		"node_modules/@mariozechner/jiti": {
-			"version": "2.6.2",
-			"resolved": "https://registry.npmjs.org/@mariozechner/jiti/-/jiti-2.6.2.tgz",
-			"integrity": "sha512-CcFowm/fDWcEMH/F47DQcdawpLQb0nw+WR+hZOv8mgAeACFJxE9uo3cXjUk/5Cl3j23t/oxvtxxUtlBCUIGeQg==",
+			"version": "2.6.5",
+			"resolved": "https://registry.npmjs.org/@mariozechner/jiti/-/jiti-2.6.5.tgz",
+			"integrity": "sha512-faGUlTcXka5l7rv0lP3K3vGW/ejRuOS24RR2aSFWREUQqzjgdsuWNo/IiPqL3kWRGt6Ahl2+qcDAwtdeWeuGUw==",
 			"license": "MIT",
 			"dependencies": {
 				"std-env": "^3.10.0",

package.json

@@ -40,6 +40,7 @@
 	},
 	"version": "0.0.3",
 	"dependencies": {
+		"@mariozechner/jiti": "^2.6.5",
 		"@mariozechner/pi-coding-agent": "^0.30.2",
 		"get-east-asian-width": "^1.4.0"
 	}

packages/coding-agent/CHANGELOG.md

@@ -19,6 +19,7 @@
 
 - Fix API key resolution after model switches by using provider argument ([#691](https://github.com/badlogic/pi-mono/pull/691) by [@joshp123](https://github.com/joshp123))
 - Fixed z.ai thinking/reasoning: thinking toggle now correctly enables/disables thinking for z.ai models ([#688](https://github.com/badlogic/pi-mono/issues/688))
+- Fixed extension loading in compiled Bun binary: extensions with local file imports now work correctly. Updated `@mariozechner/jiti` to v2.6.5 which bundles babel for Bun binary compatibility. ([#681](https://github.com/badlogic/pi-mono/issues/681))
 
 ## [0.45.3] - 2026-01-13
 

packages/coding-agent/docs/sdk.md

@@ -735,12 +735,12 @@ import {
   discoverAuthStorage,
   discoverModels,
   discoverSkills,
-  discoverHooks,
-  discoverCustomTools,
+  discoverExtensions,
   discoverContextFiles,
   discoverPromptTemplates,
   loadSettings,
   buildSystemPrompt,
+  createEventBus,
 } from "@mariozechner/pi-coding-agent";
 
 // Auth and Models
@@ -754,19 +754,16 @@ const builtIn = getModel("anthropic", "claude-opus-4-5"); // Built-in only
 // Skills
 const { skills, warnings } = discoverSkills(cwd, agentDir, skillsSettings);
 
-// Hooks (async - loads TypeScript)
-// Pass eventBus to share pi.events across hooks/tools
+// Extensions (async - loads TypeScript)
+// Pass eventBus to share pi.events across extensions
 const eventBus = createEventBus();
-const hooks = await discoverHooks(eventBus, cwd, agentDir);
-
-// Custom tools (async - loads TypeScript)
-const tools = await discoverCustomTools(eventBus, cwd, agentDir);
+const { extensions, errors } = await discoverExtensions(eventBus, cwd, agentDir);
 
 // Context files
 const contextFiles = discoverContextFiles(cwd, agentDir);
 
 // Prompt templates
-const commands = discoverPromptTemplates(cwd, agentDir);
+const templates = discoverPromptTemplates(cwd, agentDir);
 
 // Settings (global + project merged)
 const settings = loadSettings(cwd, agentDir);
@@ -816,8 +813,8 @@ import {
   SettingsManager,
   readTool,
   bashTool,
-  type HookFactory,
-  type CustomTool,
+  type ExtensionFactory,
+  type ToolDefinition,
 } from "@mariozechner/pi-coding-agent";
 
 // Set up auth storage (custom location)
@@ -831,16 +828,16 @@ if (process.env.MY_KEY) {
 // Model registry (no custom models.json)
 const modelRegistry = new ModelRegistry(authStorage);
 
-// Inline hook
-const auditHook: HookFactory = (api) => {
-  api.on("tool_call", async (event) => {
+// Inline extension
+const auditExtension: ExtensionFactory = (pi) => {
+  pi.on("tool_call", async (event) => {
     console.log(`[Audit] ${event.toolName}`);
     return undefined;
   });
 };
 
 // Inline tool
-const statusTool: CustomTool = {
+const statusTool: ToolDefinition = {
   name: "status",
   label: "Status",
   description: "Get system status",
@@ -872,8 +869,8 @@ const { session } = await createAgentSession({
   systemPrompt: "You are a minimal assistant. Be concise.",
   
   tools: [readTool, bashTool],
-  customTools: [{ tool: statusTool }],
-  hooks: [{ factory: auditHook }],
+  customTools: [statusTool],
+  extensions: [auditExtension],
   skills: [],
   contextFiles: [],
   promptTemplates: [],
@@ -961,7 +958,7 @@ The SDK is preferred when:
 - You want type safety
 - You're in the same Node.js process
 - You need direct access to agent state
-- You want to customize tools/hooks programmatically
+- You want to customize tools/extensions programmatically
 
 RPC mode is preferred when:
 - You're integrating from another language
@@ -984,12 +981,11 @@ discoverModels
 
 // Discovery
 discoverSkills
-discoverHooks
-discoverCustomTools
+discoverExtensions
 discoverContextFiles
 discoverPromptTemplates
 
-// Event Bus (for shared hook/tool communication)
+// Event Bus (for shared extension communication)
 createEventBus
 
 // Helpers
@@ -1015,8 +1011,9 @@ createGrepTool, createFindTool, createLsTool
 // Types
 type CreateAgentSessionOptions
 type CreateAgentSessionResult
-type CustomTool
-type HookFactory
+type ExtensionFactory
+type ExtensionAPI
+type ToolDefinition
 type Skill
 type PromptTemplate
 type Settings
@@ -1024,28 +1021,4 @@ type SkillsSettings
 type Tool
 ```
 
-For hook types, import from the hooks subpath:
-
-```typescript
-import type {
-  HookAPI,
-  HookMessage,
-  HookFactory,
-  HookEventContext,
-  HookCommandContext,
-  ToolCallEvent,
-  ToolResultEvent,
-} from "@mariozechner/pi-coding-agent/hooks";
-```
-
-For message utilities:
-
-```typescript
-import { isHookMessage, createHookMessage } from "@mariozechner/pi-coding-agent";
-```
-
-For config utilities:
-
-```typescript
-import { getAgentDir } from "@mariozechner/pi-coding-agent/config";
-```
+For extension types, see [extensions.md](extensions.md) for the full API.

packages/coding-agent/examples/sdk/README.md

@@ -37,9 +37,8 @@ import {
   discoverModels,
   discoverSkills,
   discoverExtensions,
-  discoverCustomTools,
   discoverContextFiles,
-  discoverSlashCommands,
+  discoverPromptTemplates,
   loadSettings,
   buildSystemPrompt,
   ModelRegistry,
@@ -92,7 +91,7 @@ const { session } = await createAgentSession({
   extensions: [{ factory: myExtension }],
   skills: [],
   contextFiles: [],
-  slashCommands: [],
+  promptTemplates: [],
   sessionManager: SessionManager.inMemory(),
 });
 
@@ -123,7 +122,7 @@ await session.prompt("Hello");
 | `additionalExtensionPaths` | `[]` | Merge with discovery |
 | `skills` | Discovered | Skills for prompt |
 | `contextFiles` | Discovered | AGENTS.md files |
-| `slashCommands` | Discovered | File commands |
+| `promptTemplates` | Discovered | Prompt templates (slash commands) |
 | `sessionManager` | `SessionManager.create(cwd)` | Persistence |
 | `settingsManager` | From agentDir | Settings overrides |
 

packages/coding-agent/src/core/extensions/loader.ts

@@ -10,6 +10,7 @@ import * as os from "node:os";
 import * as path from "node:path";
 import { fileURLToPath } from "node:url";
 import { createJiti } from "@mariozechner/jiti";
+import * as _bundledPiAgentCore from "@mariozechner/pi-agent-core";
 import * as _bundledPiAi from "@mariozechner/pi-ai";
 import type { KeyId } from "@mariozechner/pi-tui";
 import * as _bundledPiTui from "@mariozechner/pi-tui";
@@ -18,6 +19,9 @@ import * as _bundledPiTui from "@mariozechner/pi-tui";
 // The virtualModules option then makes them available to extensions.
 import * as _bundledTypebox from "@sinclair/typebox";
 import { getAgentDir, isBunBinary } from "../../config.js";
+// NOTE: This import works because loader.ts exports are NOT re-exported from index.ts,
+// avoiding a circular dependency. Extensions can import from @mariozechner/pi-coding-agent.
+import * as _bundledPiCodingAgent from "../../index.js";
 import { createEventBus, type EventBus } from "../event-bus.js";
 import type { ExecOptions } from "../exec.js";
 import { execCommand } from "../exec.js";
@@ -33,19 +37,12 @@ import type {
 } from "./types.js";
 
 /** Modules available to extensions via virtualModules (for compiled Bun binary) */
-let _lazyPiCodingAgent: unknown;
 const VIRTUAL_MODULES: Record<string, unknown> = {
 	"@sinclair/typebox": _bundledTypebox,
+	"@mariozechner/pi-agent-core": _bundledPiAgentCore,
 	"@mariozechner/pi-tui": _bundledPiTui,
 	"@mariozechner/pi-ai": _bundledPiAi,
-	// Lazy-loaded to avoid circular dependency (loader.ts is part of pi-coding-agent)
-	get "@mariozechner/pi-coding-agent"() {
-		if (!_lazyPiCodingAgent) {
-			// Dynamic require after module initialization completes
-			_lazyPiCodingAgent = require("../../index.js");
-		}
-		return _lazyPiCodingAgent;
-	},
+	"@mariozechner/pi-coding-agent": _bundledPiCodingAgent,
 };
 
 const require = createRequire(import.meta.url);
@@ -66,6 +63,7 @@ function getAliases(): Record<string, string> {
 
 	_aliases = {
 		"@mariozechner/pi-coding-agent": packageIndex,
+		"@mariozechner/pi-agent-core": require.resolve("@mariozechner/pi-agent-core"),
 		"@mariozechner/pi-tui": require.resolve("@mariozechner/pi-tui"),
 		"@mariozechner/pi-ai": require.resolve("@mariozechner/pi-ai"),
 		"@sinclair/typebox": typeboxRoot,

packages/coding-agent/src/index.ts

@@ -88,8 +88,6 @@ export type {
 	UserBashEventResult,
 } from "./core/extensions/index.js";
 export {
-	createExtensionRuntime,
-	discoverAndLoadExtensions,
 	ExtensionRunner,
 	isBashToolResult,
 	isEditToolResult,
@@ -98,7 +96,6 @@ export {
 	isLsToolResult,
 	isReadToolResult,
 	isWriteToolResult,
-	loadExtensions,
 	wrapRegisteredTool,
 	wrapRegisteredTools,
 	wrapToolsWithExtensions,