diff --git a/.gitignore b/.gitignore
index 06b88530..ddf897aa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,7 @@ node_modules
 dist
 *.tgz
 coverage
+.vite
 .vscode
 .idea
 Thumbs.db
diff --git a/src/plugin.ts b/src/plugin.ts
index 4de67a02..428c97b0 100644
--- a/src/plugin.ts
+++ b/src/plugin.ts
@@ -44,9 +44,9 @@ export function maizzle(configInput?: Partial<MaizzleConfig>): Plugin[] {
       maizzleServer = await serve({ config: configInput })
 
       // Clean up when the host server closes
-      hostServer.httpServer?.on('close', () => {
+      hostServer.httpServer?.on('close', async () => {
         if (maizzleServer) {
-          maizzleServer.close()
+          await maizzleServer.close()
           maizzleServer = null
         }
       })
diff --git a/src/serve.ts b/src/serve.ts
index ba31779f..5cf01c84 100644
--- a/src/serve.ts
+++ b/src/serve.ts
@@ -55,7 +55,7 @@ export interface ServeOptions {
   port?: number
   /** Expose the server on the network (e.g. --host) */
   host?: boolean | string
-  /** When true, suppresses the banner/URL output (used by the Vite plugin, which prints its own) */
+  /** When true, suppresses the startup banner/URL output. */
   silent?: boolean
 }
 
@@ -189,7 +189,11 @@ function maizzleDevPlugin(
 
       const userWatchPaths = config.server?.watch ?? []
       const watchPaths = [...defaultWatchPaths, ...userWatchPaths]
-      const isWatchedFile = createWatchedFileMatcher(watchPaths, config.root ?? process.cwd())
+      // Match against cwd, not config.root: the watched paths (maizzle/tailwind
+      // configs, locales) are project-root relative, and `watcher.add` below
+      // resolves them against cwd too. Using config.root would break matching
+      // when root points at a subdirectory (e.g. the Vite-plugin setup).
+      const isWatchedFile = createWatchedFileMatcher(watchPaths, process.cwd())
 
       for (const watchPath of watchPaths) {
         server.watcher.add(watchPath)
@@ -219,6 +223,10 @@ function maizzleDevPlugin(
           await renderer.close()
           renderer = await createRenderer({ dts: true, markdown: config.markdown, root: config.root, componentDirs: normalizeComponentSources(config.components?.source, process.cwd()), vite: config.vite })
 
+          // Re-register the new renderer so user-land render() calls don't keep
+          // reusing the closed one (see setActiveRenderer above).
+          setActiveRenderer(renderer)
+
           /**
            * Push UI-relevant config bits so the dev UI reacts to live edits
            * without a page reload. Uses the same shape as the initial
diff --git a/src/tests/serve.test.ts b/src/tests/serve.test.ts
new file mode 100644
index 00000000..cd2b4e01
--- /dev/null
+++ b/src/tests/serve.test.ts
@@ -0,0 +1,86 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
+import { mkdtempSync, mkdirSync, rmSync, writeFileSync } from 'node:fs'
+import { join, resolve } from 'node:path'
+import { tmpdir } from 'node:os'
+import type { ViteDevServer } from 'vite'
+import { serve } from '../serve.ts'
+import { getActiveRenderer } from '../render/active.ts'
+
+describe('serve dev server', () => {
+  let tempDir: string
+  let server: ViteDevServer | undefined
+  const originalCwd = process.cwd()
+
+  beforeEach(() => {
+    tempDir = mkdtempSync(join(tmpdir(), 'maizzle-serve-'))
+    process.chdir(tempDir)
+  })
+
+  afterEach(async () => {
+    await server?.close()
+    server = undefined
+    process.chdir(originalCwd)
+    rmSync(tempDir, { recursive: true, force: true })
+  })
+
+  it('refreshes the active renderer when the config file changes', async () => {
+    writeFileSync(join(tempDir, 'maizzle.config.js'), 'export default {}\n')
+
+    server = await serve({ port: 3157, silent: true })
+
+    const before = getActiveRenderer()
+    expect(before).toBeTruthy()
+
+    // Drive the watcher's config-change branch directly.
+    server.watcher.emit('change', resolve(tempDir, 'maizzle.config.js'))
+
+    await vi.waitFor(() => {
+      const after = getActiveRenderer()
+      expect(after).toBeTruthy()
+      expect(after).not.toBe(before)
+    }, { timeout: 15000, interval: 100 })
+  }, 30000)
+
+  it('detects a root-level config change when config.root is a subdirectory', async () => {
+    writeFileSync(join(tempDir, 'maizzle.config.js'), 'export default {}\n')
+    mkdirSync(join(tempDir, 'emails'), { recursive: true })
+
+    server = await serve({ config: { root: 'emails' }, port: 3157, silent: true })
+
+    const before = getActiveRenderer()
+
+    // Config file lives at cwd, not under root — the watcher must still match it.
+    server.watcher.emit('change', resolve(tempDir, 'maizzle.config.js'))
+
+    await vi.waitFor(() => {
+      expect(getActiveRenderer()).not.toBe(before)
+    }, { timeout: 15000, interval: 100 })
+  }, 30000)
+
+  it('clears the active renderer on close', async () => {
+    server = await serve({ port: 3157, silent: true })
+    expect(getActiveRenderer()).toBeTruthy()
+
+    await server.close()
+    server = undefined
+
+    expect(getActiveRenderer()).toBeNull()
+  }, 30000)
+
+  it('emits a template-updated HMR event when a template changes', async () => {
+    server = await serve({ port: 3157, silent: true })
+
+    const events: string[] = []
+    const origSend = server.ws.send.bind(server.ws)
+    server.ws.send = ((payload: any) => {
+      if (payload?.type === 'custom') events.push(payload.event)
+      return origSend(payload)
+    }) as typeof server.ws.send
+
+    server.watcher.emit('change', resolve(tempDir, 'emails/welcome.vue'))
+
+    await vi.waitFor(() => {
+      expect(events).toContain('maizzle:template-updated')
+    }, { timeout: 15000, interval: 100 })
+  }, 30000)
+})
diff --git a/src/types/config.ts b/src/types/config.ts
index 6d7fc270..f38eab78 100644
--- a/src/types/config.ts
+++ b/src/types/config.ts
@@ -717,9 +717,10 @@ export interface MaizzleConfig {
   /**
    * Vite configuration options passed to the internal Vite SSR server.
    *
-   * Use this to add custom Vite plugins or other Vite options.
-   * If a `vite.config.{ts,js}` file exists in the project root, it takes
-   * precedence and this option is used as a fallback.
+   * Use this to add custom Vite plugins or other Vite options. The internal
+   * SSR server never loads a project `vite.config.{ts,js}` (it runs with
+   * `configFile: false`), so pass anything it needs here. These options are
+   * merged underneath Maizzle's required settings, which take precedence.
    *
    * @example
    * vite: {
diff --git a/vitest.config.ts b/vitest.config.ts
index 3bb06d0d..5d39dffa 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -1,4 +1,4 @@
-import { defineConfig } from 'vitest/config'
+import { defineConfig, coverageConfigDefaults } from 'vitest/config'
 import vue from '@vitejs/plugin-vue'
 
 export default defineConfig({
@@ -6,5 +6,16 @@ export default defineConfig({
   test: {
     globals: true,
     environment: 'happy-dom',
+    coverage: {
+      exclude: [
+        ...coverageConfigDefaults.exclude,
+        // Dev-server surfaces: the SSR bootstrap and the dev-UI/middleware
+        // (rendering, linting, compatibility checks, email sending). These are
+        // exercised by the running dev server, not unit tests, so they're
+        // excluded to keep the coverage number meaningful for the library core.
+        'src/serve.ts',
+        'src/server/**',
+      ],
+    },
   },
 })