fix(coding-agent): avoid Windows self-update native locks

closes #4157

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed Windows npm self-updates to move loaded native dependency packages out of the active install before reinstalling pi ([#4157](https://github.com/earendil-works/pi/issues/4157)).
+
 ## [0.75.1] - 2026-05-18
 
 ### Fixed

packages/coding-agent/src/main.ts

@@ -15,7 +15,7 @@ import { processFileArguments } from "./cli/file-processor.js";
 import { buildInitialMessage } from "./cli/initial-message.js";
 import { listModels } from "./cli/list-models.js";
 import { selectSession } from "./cli/session-picker.js";
-import { ENV_SESSION_DIR, expandTildePath, getAgentDir, VERSION } from "./config.js";
+import { ENV_SESSION_DIR, expandTildePath, getAgentDir, getPackageDir, VERSION } from "./config.js";
 import { type CreateAgentSessionRuntimeFactory, createAgentSessionRuntime } from "./core/agent-session-runtime.js";
 import {
 	type AgentSessionRuntimeDiagnostic,
@@ -46,6 +46,7 @@ import { ExtensionSelectorComponent } from "./modes/interactive/components/exten
 import { initTheme, stopThemeWatcher } from "./modes/interactive/theme/theme.js";
 import { handleConfigCommand, handlePackageCommand } from "./package-manager-cli.js";
 import { isLocalPath } from "./utils/paths.js";
+import { cleanupWindowsSelfUpdateQuarantine } from "./utils/windows-self-update.js";
 
 /**
  * Read all content from piped stdin.
@@ -428,6 +429,10 @@ export async function main(args: string[], options?: MainOptions) {
 		process.env.PI_SKIP_VERSION_CHECK = "1";
 	}
 
+	if (process.platform === "win32") {
+		cleanupWindowsSelfUpdateQuarantine(getPackageDir());
+	}
+
 	if (await handlePackageCommand(args)) {
 		return;
 	}

packages/coding-agent/src/package-manager-cli.ts

@@ -3,7 +3,9 @@ import { spawn } from "child_process";
 import { selectConfig } from "./cli/config-selector.js";
 import {
 	APP_NAME,
+	detectInstallMethod,
 	getAgentDir,
+	getPackageDir,
 	getSelfUpdateCommand,
 	getSelfUpdateUnavailableInstruction,
 	PACKAGE_NAME,
@@ -14,6 +16,10 @@ import { DefaultPackageManager } from "./core/package-manager.js";
 import { SettingsManager } from "./core/settings-manager.js";
 import { resolveSpawnCommand } from "./utils/child-process.js";
 import { getLatestPiRelease, isNewerPackageVersion } from "./utils/version-check.js";
+import {
+	cleanupWindowsSelfUpdateQuarantine,
+	quarantineWindowsNativeDependencies,
+} from "./utils/windows-self-update.js";
 
 export type PackageCommand = "install" | "remove" | "update" | "list";
 
@@ -336,6 +342,16 @@ async function runSelfUpdate(command: SelfUpdateCommand): Promise<void> {
 	}
 }
 
+function prepareWindowsNpmSelfUpdate(): void {
+	if (process.platform !== "win32") {
+		return;
+	}
+
+	const packageDir = getPackageDir();
+	cleanupWindowsSelfUpdateQuarantine(packageDir);
+	quarantineWindowsNativeDependencies(packageDir);
+}
+
 export async function handleConfigCommand(args: string[]): Promise<boolean> {
 	if (args[0] !== "config") {
 		return false;
@@ -489,6 +505,13 @@ export async function handlePackageCommand(args: string[]): Promise<boolean> {
 					if (!selfUpdatePlan.shouldRun) {
 						return true;
 					}
+					const installMethod = detectInstallMethod();
+					if (process.platform === "win32" && installMethod !== "npm") {
+						console.error(chalk.red(`${APP_NAME} self-update on Windows is only supported for npm installs.`));
+						console.error(chalk.dim(`Detected install method: ${installMethod}. Update ${APP_NAME} manually.`));
+						process.exitCode = 1;
+						return true;
+					}
 					const selfUpdateCommand = getSelfUpdateCommand(
 						PACKAGE_NAME,
 						selfUpdateNpmCommand,
@@ -500,6 +523,7 @@ export async function handlePackageCommand(args: string[]): Promise<boolean> {
 						return true;
 					}
 					try {
+						prepareWindowsNpmSelfUpdate();
 						await runSelfUpdate(selfUpdateCommand);
 					} catch (error: unknown) {
 						const message = error instanceof Error ? error.message : "Unknown package command error";

packages/coding-agent/src/utils/windows-self-update.ts

@@ -0,0 +1,84 @@
+import { randomUUID } from "node:crypto";
+import { copyFileSync, existsSync, mkdirSync, renameSync, rmSync } from "node:fs";
+import { basename, dirname, join, relative, resolve, toNamespacedPath } from "node:path";
+import { getCwdRelativePath } from "./paths.js";
+
+const QUARANTINE_DIR_NAME = ".pi-native-quarantine";
+
+function normalizePath(path: string): string {
+	return toNamespacedPath(resolve(path));
+}
+
+function getQuarantineRoot(packageDir: string): string | undefined {
+	let current = resolve(packageDir);
+	while (true) {
+		if (basename(current).toLowerCase() === "node_modules") {
+			return join(current, QUARANTINE_DIR_NAME);
+		}
+		const parent = dirname(current);
+		if (parent === current) {
+			return undefined;
+		}
+		current = parent;
+	}
+}
+
+function getLoadedSharedObjectsInPackageDir(packageDir: string): string[] {
+	const sharedObjects = (process.report.getReport() as { sharedObjects?: unknown }).sharedObjects;
+	if (!Array.isArray(sharedObjects)) {
+		return [];
+	}
+
+	const root = normalizePath(packageDir).toLowerCase();
+	const seen = new Set<string>();
+	const loadedFiles: string[] = [];
+	for (const value of sharedObjects) {
+		if (typeof value !== "string") {
+			continue;
+		}
+		const filePath = normalizePath(value);
+		const comparisonPath = filePath.toLowerCase();
+		if (getCwdRelativePath(comparisonPath, root) === undefined || seen.has(comparisonPath)) {
+			continue;
+		}
+		seen.add(comparisonPath);
+		loadedFiles.push(filePath);
+	}
+	return loadedFiles;
+}
+
+export function cleanupWindowsSelfUpdateQuarantine(packageDir: string): void {
+	const quarantineRoot = getQuarantineRoot(packageDir);
+	if (!quarantineRoot) {
+		return;
+	}
+	try {
+		rmSync(quarantineRoot, { recursive: true, force: true });
+	} catch {
+		// A previous pi process may still be exiting and holding a native addon.
+	}
+}
+
+export function quarantineWindowsNativeDependencies(packageDir: string): void {
+	const resolvedPackageDir = normalizePath(packageDir);
+	const quarantineRoot = getQuarantineRoot(resolvedPackageDir);
+	if (!quarantineRoot) {
+		return;
+	}
+
+	const loadedFiles = getLoadedSharedObjectsInPackageDir(resolvedPackageDir);
+	if (loadedFiles.length === 0) {
+		return;
+	}
+
+	const quarantineRunDir = join(quarantineRoot, `${Date.now()}-${process.pid}-${randomUUID()}`);
+	for (const loadedFile of loadedFiles) {
+		if (!existsSync(loadedFile)) {
+			continue;
+		}
+		const quarantinePath = join(quarantineRunDir, relative(resolvedPackageDir, loadedFile));
+		mkdirSync(dirname(quarantinePath), { recursive: true });
+		renameSync(loadedFile, quarantinePath);
+		copyFileSync(quarantinePath, loadedFile);
+	}
+}