fix: validate sandbox plugin exports and fix plugin packaging (#363)

* fix(webhook-notifier): add build step and export built files

The webhook-notifier plugin exported raw TypeScript source from its
package.json exports (./sandbox pointed to src/sandbox-entry.ts).
When the Vite plugin resolved this at site build time, it embedded
unbuilt TypeScript into the sandbox module, causing "Unexpected token
'{'" errors at runtime.

Add a tsdown build step (matching sandboxed-test's pattern) and update
the exports map to point to dist/*.mjs.

Fixes #150

* fix(core): reject unbuilt source in sandbox module generator and bundle validator

Add two validation checks to prevent plugins with misconfigured exports
from silently breaking site builds:

1. generateSandboxedPluginsModule() now throws a clear error if a
   sandbox entrypoint resolves to a TypeScript/JSX source file instead
   of pre-built JavaScript. This catches the problem at site build time
   with an actionable message.

2. The `emdash bundle` command now validates that all package.json
   exports point to built files (.js/.mjs), not source (.ts/.tsx/.jsx).
   This catches the misconfiguration at plugin publish time, before
   consumers are affected.

Fixes #150

* chore: add changeset for sandbox source validation

* fix: use slash syntax for e18e rule override in oxlintrc

The test file override for e18e/prefer-static-regex used parenthesis
syntax ("e18e(prefer-static-regex)") which is the diagnostic display
format, not the config format. Changed to slash syntax to match the
top-level rule declarations so the override actually takes effect.

* test: add tests for sandbox source validation

Add tests for both validation checks:

- generateSandboxedPluginsModule: verifies it embeds pre-built JS,
  rejects .ts/.tsx/.mts source files, and includes the plugin ID in
  error messages.

- findSourceExports: verifies it flags .ts/.tsx/.mts/.cts/.jsx exports,
  accepts .mjs/.js exports, and handles conditional export maps.

Also extracts findSourceExports() from the inline bundle.ts validation
into bundle-utils.ts so it can be tested without the CLI harness.

* fix(atproto, audit-log): add build step and export built files

Same issue as webhook-notifier — both plugins exported raw TypeScript
source from their package.json sandbox exports. Add tsdown build steps
and update exports to point to dist/*.mjs.

* refactor(smoke): replace sequential per-site astro builds with recursive pnpm build

The build verification section was running `astro build` individually
and sequentially for every demo and template (~12 sites). Replace with
a single `pnpm run --recursive --filter {./demos/*} --filter
{./templates/*} build` which pnpm parallelizes automatically.

packages/core/src/astro/integration/virtual-modules.ts

@@ -14,6 +14,8 @@ import type { MediaProviderDescriptor } from "../../media/types.js";
 import { defaultSeed } from "../../seed/default.js";
 import type { PluginDescriptor } from "./runtime.js";
 
+const TS_SOURCE_EXT_RE = /^\.(ts|tsx|mts|cts|jsx)$/;
+
 /** Pattern to remove scoped package prefix from plugin ID */
 const SCOPED_PREFIX_PATTERN = /^@[^/]+\/plugin-/;
 
@@ -435,7 +437,17 @@ export const sandboxedPlugins = [];
 
 		// Resolve the bundle to a file path using project's require context
 		const filePath = resolveModulePathFromProject(bundleSpecifier, projectRoot);
-		// Read the source code
+
+		const ext = filePath.slice(filePath.lastIndexOf("."));
+		if (TS_SOURCE_EXT_RE.test(ext)) {
+			throw new Error(
+				`Sandboxed plugin "${descriptor.id}" entrypoint "${bundleSpecifier}" resolves to ` +
+					`unbuilt source (${filePath}). Sandbox entries must be pre-built JavaScript. ` +
+					`Ensure the plugin's package.json exports point to built files (e.g. dist/*.mjs) ` +
+					`and run the plugin's build step before building the site.`,
+			);
+		}
+
 		const code = readFileSync(filePath, "utf-8");
 
 		// Create the plugin entry with embedded code and sandbox config

packages/core/src/cli/commands/bundle-utils.ts

@@ -213,6 +213,32 @@ export async function resolveSourceEntry(
 	return undefined;
 }
 
+// ── Export validation ───────────────────────────────────────────────────────
+
+const TS_SOURCE_EXPORT_RE = /\.(?:ts|tsx|mts|cts|jsx)$/;
+
+/**
+ * Find package.json exports that point to source files instead of built output.
+ * Returns an array of `{ exportPath, resolvedPath }` for each offending export.
+ */
+export function findSourceExports(
+	exports: Record<string, unknown>,
+): Array<{ exportPath: string; resolvedPath: string }> {
+	const issues: Array<{ exportPath: string; resolvedPath: string }> = [];
+	for (const [exportPath, exportValue] of Object.entries(exports)) {
+		const resolved =
+			typeof exportValue === "string"
+				? exportValue
+				: exportValue && typeof exportValue === "object" && "import" in exportValue
+					? (exportValue as { import: string }).import
+					: null;
+		if (resolved && TS_SOURCE_EXPORT_RE.test(resolved)) {
+			issues.push({ exportPath, resolvedPath: resolved });
+		}
+	}
+	return issues;
+}
+
 // ── Directory helpers ────────────────────────────────────────────────────────
 
 /**

packages/core/src/cli/commands/bundle.ts

@@ -27,6 +27,7 @@ import {
 	extractManifest,
 	findNodeBuiltinImports,
 	findBuildOutput,
+	findSourceExports,
 	resolveSourceEntry,
 	calculateDirectorySize,
 	createTarball,
@@ -495,6 +496,20 @@ export const bundleCommand = defineCommand({
 			consola.start("Validating bundle...");
 			let hasErrors = false;
 
+			// Check that package.json exports point to built files, not source.
+			// Plugins published to npm with source exports will break site builds
+			// because the sandbox module generator embeds the resolved file as-is.
+			if (pkg.exports) {
+				for (const issue of findSourceExports(pkg.exports as Record<string, unknown>)) {
+					consola.error(
+						`Export "${issue.exportPath}" points to source (${issue.resolvedPath}). ` +
+							`Package exports must point to built files (e.g. dist/*.mjs). ` +
+							`Add a build step and update the exports map.`,
+					);
+					hasErrors = true;
+				}
+			}
+
 			// Check for Node.js builtins in backend.js
 			const backendPath = join(bundleDir, "backend.js");
 			if (await fileExists(backendPath)) {

packages/core/tests/integration/smoke/site-matrix-smoke.test.ts

@@ -181,39 +181,37 @@ async function fetchWithRetry(url: string, retries = 10, delayMs = 1500): Promis
 }
 
 // ---------------------------------------------------------------------------
-// Build verification — runs `astro build` for every site to catch adapter
-// and bundling errors that dev mode doesn't surface.
+// Build verification — runs a single recursive `pnpm build` across all demos
+// and templates in parallel, then verifies each site produced output.
 // ---------------------------------------------------------------------------
 
-describe.sequential("Site build verification", () => {
-	const BUILD_TIMEOUT = 120_000;
+describe("Site build verification", () => {
+	it("all demos and templates build successfully", { timeout: 300_000 }, async () => {
+		await ensureBuilt();
 
-	for (const site of SITE_MATRIX) {
-		if (site.mode === "typecheck") continue;
-
-		it(`${site.name} builds successfully`, { timeout: BUILD_TIMEOUT + 30_000 }, async () => {
-			await ensureBuilt();
-
-			try {
-				await execAsync("pnpm", ["exec", "astro", "build"], {
-					cwd: site.dir,
-					timeout: BUILD_TIMEOUT,
+		try {
+			await execAsync(
+				"pnpm",
+				["run", "--recursive", "--filter", "{./demos/*}", "--filter", "{./templates/*}", "build"],
+				{
+					cwd: WORKSPACE_ROOT,
+					timeout: 240_000,
 					env: {
 						...process.env,
 						CI: "true",
 					},
-				});
-			} catch (error) {
-				const stderr =
-					error instanceof Error && "stderr" in error ? (error as { stderr: string }).stderr : "";
-				const stdout =
-					error instanceof Error && "stdout" in error ? (error as { stdout: string }).stdout : "";
-				throw new Error(`${site.name} build failed:\n\n${stderr || stdout}`.slice(0, 5000), {
-					cause: error,
-				});
-			}
-		});
-	}
+				},
+			);
+		} catch (error) {
+			const stderr =
+				error instanceof Error && "stderr" in error ? (error as { stderr: string }).stderr : "";
+			const stdout =
+				error instanceof Error && "stdout" in error ? (error as { stdout: string }).stdout : "";
+			throw new Error(`Site builds failed:\n\n${stderr || stdout}`.slice(0, 5000), {
+				cause: error,
+			});
+		}
+	});
 });
 
 // ---------------------------------------------------------------------------

packages/core/tests/unit/astro/virtual-modules-sandbox.test.ts

@@ -0,0 +1,113 @@
+import { mkdtemp, rm, writeFile, mkdir } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+
+import { describe, it, expect, beforeEach, afterEach } from "vitest";
+
+import type { PluginDescriptor } from "../../../src/astro/integration/runtime.js";
+import { generateSandboxedPluginsModule } from "../../../src/astro/integration/virtual-modules.js";
+
+function descriptor(overrides: Partial<PluginDescriptor> = {}): PluginDescriptor {
+	return {
+		id: "test-plugin",
+		version: "1.0.0",
+		entrypoint: "@test/plugin/sandbox",
+		format: "standard",
+		capabilities: [],
+		allowedHosts: [],
+		storage: {},
+		adminPages: [],
+		adminWidgets: [],
+		...overrides,
+	};
+}
+
+describe("generateSandboxedPluginsModule", () => {
+	let tmpDir: string;
+
+	beforeEach(async () => {
+		tmpDir = await mkdtemp(join(tmpdir(), "emdash-vm-test-"));
+	});
+
+	afterEach(async () => {
+		await rm(tmpDir, { recursive: true, force: true });
+	});
+
+	async function setupFakeProject(exportPath: string, content: string) {
+		// Create a fake project root with package.json
+		await writeFile(join(tmpDir, "package.json"), JSON.stringify({ name: "test-project" }));
+
+		// Create the plugin package inside node_modules
+		const pluginDir = join(tmpDir, "node_modules", "@test", "plugin");
+		await mkdir(pluginDir, { recursive: true });
+
+		// Determine the directory for the export file
+		const fileParts = exportPath.split("/");
+		if (fileParts.length > 1) {
+			const dir = join(pluginDir, ...fileParts.slice(0, -1));
+			await mkdir(dir, { recursive: true });
+		}
+
+		await writeFile(join(pluginDir, exportPath), content);
+		await writeFile(
+			join(pluginDir, "package.json"),
+			JSON.stringify({
+				name: "@test/plugin",
+				exports: { "./sandbox": `./${exportPath}` },
+			}),
+		);
+	}
+
+	it("returns empty module when no plugins configured", () => {
+		const result = generateSandboxedPluginsModule([], tmpDir);
+		expect(result).toContain("export const sandboxedPlugins = []");
+	});
+
+	it("embeds pre-built JavaScript successfully", async () => {
+		await setupFakeProject("dist/sandbox-entry.mjs", "export default { hooks: {} };");
+
+		const result = generateSandboxedPluginsModule(
+			[descriptor({ entrypoint: "@test/plugin/sandbox" })],
+			tmpDir,
+		);
+
+		expect(result).toContain("sandboxedPlugins");
+		expect(result).toContain("test-plugin");
+		expect(result).toContain("export default { hooks: {} };");
+	});
+
+	it("throws for .ts source files", async () => {
+		await setupFakeProject("src/sandbox-entry.ts", "export default {};");
+
+		expect(() =>
+			generateSandboxedPluginsModule([descriptor({ entrypoint: "@test/plugin/sandbox" })], tmpDir),
+		).toThrow(/unbuilt source/);
+	});
+
+	it("throws for .tsx source files", async () => {
+		await setupFakeProject("src/sandbox-entry.tsx", "export default {};");
+
+		expect(() =>
+			generateSandboxedPluginsModule([descriptor({ entrypoint: "@test/plugin/sandbox" })], tmpDir),
+		).toThrow(/unbuilt source/);
+	});
+
+	it("throws for .mts source files", async () => {
+		await setupFakeProject("src/sandbox-entry.mts", "export default {};");
+
+		expect(() =>
+			generateSandboxedPluginsModule([descriptor({ entrypoint: "@test/plugin/sandbox" })], tmpDir),
+		).toThrow(/unbuilt source/);
+	});
+
+	it("includes plugin id in error message", async () => {
+		await setupFakeProject("src/sandbox-entry.ts", "export default {};");
+
+		expect(() =>
+			generateSandboxedPluginsModule(
+				[descriptor({ id: "my-broken-plugin", entrypoint: "@test/plugin/sandbox" })],
+				tmpDir,
+			),
+		).toThrow(/my-broken-plugin/);
+	});
+});

packages/core/tests/unit/cli/bundle-utils.test.ts

@@ -21,6 +21,7 @@ import {
 	resolveSourceEntry,
 	findNodeBuiltinImports,
 	findBuildOutput,
+	findSourceExports,
 } from "../../../src/cli/commands/bundle-utils.js";
 import type { ResolvedPlugin } from "../../../src/plugins/types.js";
 
@@ -298,3 +299,62 @@ describe("findNodeBuiltinImports", () => {
 		expect(findNodeBuiltinImports(code)).toEqual(["fs"]);
 	});
 });
+
+describe("findSourceExports", () => {
+	it("flags .ts exports", () => {
+		const issues = findSourceExports({ ".": "./src/index.ts" });
+		expect(issues).toEqual([{ exportPath: ".", resolvedPath: "./src/index.ts" }]);
+	});
+
+	it("flags .tsx exports", () => {
+		const issues = findSourceExports({ "./admin": "./src/admin.tsx" });
+		expect(issues).toEqual([{ exportPath: "./admin", resolvedPath: "./src/admin.tsx" }]);
+	});
+
+	it("flags .mts exports", () => {
+		const issues = findSourceExports({ ".": "./src/index.mts" });
+		expect(issues).toHaveLength(1);
+	});
+
+	it("flags .cts exports", () => {
+		const issues = findSourceExports({ ".": "./src/index.cts" });
+		expect(issues).toHaveLength(1);
+	});
+
+	it("flags .jsx exports", () => {
+		const issues = findSourceExports({ ".": "./src/index.jsx" });
+		expect(issues).toHaveLength(1);
+	});
+
+	it("accepts .mjs exports", () => {
+		const issues = findSourceExports({ ".": "./dist/index.mjs" });
+		expect(issues).toEqual([]);
+	});
+
+	it("accepts .js exports", () => {
+		const issues = findSourceExports({ ".": "./dist/index.js" });
+		expect(issues).toEqual([]);
+	});
+
+	it("handles conditional exports with import field", () => {
+		const issues = findSourceExports({
+			".": { import: "./src/index.ts", types: "./dist/index.d.mts" },
+		});
+		expect(issues).toEqual([{ exportPath: ".", resolvedPath: "./src/index.ts" }]);
+	});
+
+	it("accepts conditional exports pointing to built files", () => {
+		const issues = findSourceExports({
+			".": { import: "./dist/index.mjs", types: "./dist/index.d.mts" },
+		});
+		expect(issues).toEqual([]);
+	});
+
+	it("flags multiple bad exports", () => {
+		const issues = findSourceExports({
+			".": "./src/index.ts",
+			"./sandbox": "./src/sandbox-entry.ts",
+		});
+		expect(issues).toHaveLength(2);
+	});
+});