diff --git a/examples/snowpack/astro/layouts/content-with-cover.astro b/examples/snowpack/astro/layouts/content-with-cover.astro
index ac84f6354..46006bdfb 100644
--- a/examples/snowpack/astro/layouts/content-with-cover.astro
+++ b/examples/snowpack/astro/layouts/content-with-cover.astro
@@ -7,6 +7,7 @@ import BaseLayout from '../components/BaseLayout.astro';
 export let content: any;
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/examples/snowpack/astro/layouts/content.astro b/examples/snowpack/astro/layouts/content.astro
index 8a7504264..c8f9ca907 100644
--- a/examples/snowpack/astro/layouts/content.astro
+++ b/examples/snowpack/astro/layouts/content.astro
@@ -7,6 +7,7 @@ import BaseLayout from '../components/BaseLayout.astro';
 export let content: any;
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/examples/snowpack/astro/layouts/post.astro b/examples/snowpack/astro/layouts/post.astro
index 8f0a3c52b..05f28bf24 100644
--- a/examples/snowpack/astro/layouts/post.astro
+++ b/examples/snowpack/astro/layouts/post.astro
@@ -6,6 +6,7 @@ import { format as formatDate, parseISO } from 'date-fns';
 export let content: any;
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/examples/snowpack/astro/pages/404.astro b/examples/snowpack/astro/pages/404.astro
index 4677ed50d..053c931f4 100644
--- a/examples/snowpack/astro/pages/404.astro
+++ b/examples/snowpack/astro/pages/404.astro
@@ -6,6 +6,7 @@ let title = 'Not Found';
 let description = 'Snowpack is a lightning-fast frontend build tool, designed for the modern web.';
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/examples/snowpack/astro/pages/guides.astro b/examples/snowpack/astro/pages/guides.astro
index 608283243..e02856ede 100644
--- a/examples/snowpack/astro/pages/guides.astro
+++ b/examples/snowpack/astro/pages/guides.astro
@@ -40,6 +40,7 @@ let communityGuides;
   });
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/examples/snowpack/astro/pages/index.astro b/examples/snowpack/astro/pages/index.astro
index 31dba0f51..aa5ee59b6 100644
--- a/examples/snowpack/astro/pages/index.astro
+++ b/examples/snowpack/astro/pages/index.astro
@@ -8,8 +8,8 @@ let title = 'Snowpack';
 let description = 'Snowpack is a lightning-fast frontend build tool, designed for the modern web.';
 ---
 
+<!doctype html>
 <html>
-
 <head>
   <style lang="scss">
     @use '../../public/css/var' as *;
@@ -149,5 +149,4 @@ let description = 'Snowpack is a lightning-fast frontend build tool, designed fo
   <!-- Place this tag in your head or just before your close body tag. -->
   <script async="async" defer="defer" src="https://buttons.github.io/buttons.js"></script>
 </body>
-
 </html>
diff --git a/examples/snowpack/astro/pages/news.astro b/examples/snowpack/astro/pages/news.astro
index bd1c7b309..bae3e5ad7 100644
--- a/examples/snowpack/astro/pages/news.astro
+++ b/examples/snowpack/astro/pages/news.astro
@@ -16,6 +16,7 @@ const title = 'Community & News';
 const description = 'Snowpack community news and companies that use Snowpack.';
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/examples/snowpack/astro/pages/plugins.astro b/examples/snowpack/astro/pages/plugins.astro
index faae4a26d..bffe9b4b9 100644
--- a/examples/snowpack/astro/pages/plugins.astro
+++ b/examples/snowpack/astro/pages/plugins.astro
@@ -7,6 +7,7 @@ let title = 'The Snowpack Plugin Catalog';
 let description = 'Snowpack plugins allow for configuration-minimal tooling integration.';
 ---
 
+<!doctype html>
 <html>
 
 <head>
diff --git a/src/@types/optimizer.ts b/src/@types/optimizer.ts
index b9e228f3e..22027d2e2 100644
--- a/src/@types/optimizer.ts
+++ b/src/@types/optimizer.ts
@@ -1,6 +1,6 @@
 import type { TemplateNode } from '../parser/interfaces';
 
-export type VisitorFn = (node: TemplateNode) => void;
+export type VisitorFn = (node: TemplateNode, parent: TemplateNode, type: string, index: number) => void;
 
 export interface NodeVisitor {
   enter?: VisitorFn;
diff --git a/src/compiler/optimize/doctype.ts b/src/compiler/optimize/doctype.ts
new file mode 100644
index 000000000..a666876bf
--- /dev/null
+++ b/src/compiler/optimize/doctype.ts
@@ -0,0 +1,33 @@
+import { Optimizer } from '../../@types/optimizer';
+
+export default function (_opts: { filename: string; fileID: string }): Optimizer {
+  let hasDoctype = false;
+
+  return {
+    visitors: {
+      html: {
+        Element: {
+          enter(node, parent, _key, index) {
+            if(node.name === '!doctype') {
+              hasDoctype = true;
+            }
+            if(node.name === 'html' && !hasDoctype) {
+              const dtNode = {
+                start: 0, end: 0,
+                attributes: [{ type: 'Attribute', name: 'html', value: true, start: 0, end: 0 }],
+                children: [],
+                name: '!doctype',
+                type: 'Element'
+              };
+              parent.children!.splice(index, 0, dtNode);
+              hasDoctype = true;
+            }
+          }
+        }
+      }
+    },
+    async finalize() {
+      // Nothing happening here.
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/compiler/optimize/index.ts b/src/compiler/optimize/index.ts
index aa5ca58f3..d86ce3c24 100644
--- a/src/compiler/optimize/index.ts
+++ b/src/compiler/optimize/index.ts
@@ -1,7 +1,10 @@
 import { walk } from 'estree-walker';
 import type { Ast, TemplateNode } from '../../parser/interfaces';
 import { NodeVisitor, Optimizer, VisitorFn } from '../../@types/optimizer';
+
+// Optimizers
 import optimizeStyles from './styles.js';
+import optimizeDoctype from './doctype.js';
 
 interface VisitorCollection {
   enter: Map<string, VisitorFn[]>;
@@ -44,19 +47,19 @@ function createVisitorCollection() {
 
 function walkAstWithVisitors(tmpl: TemplateNode, collection: VisitorCollection) {
   walk(tmpl, {
-    enter(node) {
+    enter(node, parent, key, index) {
       if (collection.enter.has(node.type)) {
         const fns = collection.enter.get(node.type)!;
         for (let fn of fns) {
-          fn(node);
+          fn(node, parent, key, index);
         }
       }
     },
-    leave(node) {
+    leave(node, parent, key, index) {
       if (collection.leave.has(node.type)) {
         const fns = collection.leave.get(node.type)!;
         for (let fn of fns) {
-          fn(node);
+          fn(node, parent, key, index);
         }
       }
     },
@@ -73,7 +76,7 @@ export async function optimize(ast: Ast, opts: OptimizeOptions) {
   const cssVisitors = createVisitorCollection();
   const finalizers: Array<() => Promise<void>> = [];
 
-  const optimizers = [optimizeStyles(opts)];
+  const optimizers = [optimizeStyles(opts), optimizeDoctype(opts)];
 
   for (const optimizer of optimizers) {
     collectVisitors(optimizer, htmlVisitors, cssVisitors, finalizers);
diff --git a/src/frontend/h.ts b/src/frontend/h.ts
index cd94583f8..70965e135 100644
--- a/src/frontend/h.ts
+++ b/src/frontend/h.ts
@@ -6,6 +6,15 @@ export type HTag = string | AstroComponent;
 const voidTags = new Set(['area', 'base', 'br', 'col', 'command', 'embed', 'hr', 'img', 'input', 'keygen', 'link', 'meta', 'param', 'source', 'track', 'wbr']);
 
 function* _h(tag: string, attrs: HProps, children: Array<HChild>) {
+  if(tag === '!doctype') {
+    yield '<!doctype ';
+    if(attrs) {
+      yield Object.keys(attrs).join(' ');
+    }
+    yield '>';
+    return;
+  }
+
   yield `<${tag}`;
   if (attrs) {
     yield ' ';
diff --git a/src/runtime.ts b/src/runtime.ts
index ac6d4664a..1b7261dfc 100644
--- a/src/runtime.ts
+++ b/src/runtime.ts
@@ -2,12 +2,14 @@ import type { SnowpackDevServer, ServerRuntime as SnowpackServerRuntime, LoadRes
 import type { AstroConfig } from './@types/astro';
 import type { LogOptions } from './logger';
 import type { CompileError } from './parser/utils/error.js';
-import { info, error, parseError } from './logger.js';
+import { info } from './logger.js';
 
-import { existsSync, promises as fsPromises } from 'fs';
-import { loadConfiguration, startServer as startSnowpackServer } from 'snowpack';
-
-const { readFile } = fsPromises;
+import { existsSync } from 'fs';
+import {
+  loadConfiguration,
+  logger as snowpackLogger,
+  startServer as startSnowpackServer
+} from 'snowpack';
 
 interface RuntimeConfig {
   astroConfig: AstroConfig;
@@ -27,6 +29,9 @@ type LoadResultError = { statusCode: 500 } & ({ type: 'parse-error'; error: Comp
 
 export type LoadResult = LoadResultSuccess | LoadResultNotFound | LoadResultError;
 
+// Disable snowpack from writing to stdout/err.
+snowpackLogger.level = 'silent';
+
 async function load(config: RuntimeConfig, rawPathname: string | undefined): Promise<LoadResult> {
   const { logging, snowpack, snowpackRuntime } = config;
   const { astroRoot } = config.astroConfig;
@@ -130,13 +135,18 @@ export async function createRuntime(astroConfig: AstroConfig, { logging }: Runti
     resolve: async (pkgName: string) => snowpack.getUrlForPackage(pkgName),
   };
 
+  const mountOptions = {
+    [astroRoot.pathname]: '/_astro',
+    [internalPath.pathname]: '/_astro_internal'
+  }
+
+  if(existsSync(astroConfig.public)) {
+    mountOptions[astroConfig.public.pathname] = '/';
+  }
+
   const snowpackConfig = await loadConfiguration({
     root: projectRoot.pathname,
-    mount: {
-      [astroRoot.pathname]: '/_astro',
-      [internalPath.pathname]: '/_astro_internal',
-      public: '/',
-    },
+    mount: mountOptions,
     plugins: [[new URL('../snowpack-plugin.cjs', import.meta.url).pathname, astroPlugOptions], '@snowpack/plugin-sass', '@snowpack/plugin-svelte', '@snowpack/plugin-vue'],
     devOptions: {
       open: 'none',
diff --git a/test/astro-basic.test.js b/test/astro-basic.test.js
index 79b71cfa7..606a94679 100644
--- a/test/astro-basic.test.js
+++ b/test/astro-basic.test.js
@@ -1,6 +1,7 @@
 import { suite } from 'uvu';
 import * as assert from 'uvu/assert';
 import { createRuntime } from '../lib/runtime.js';
+import { loadConfig } from '../lib/config.js';
 import { doc } from './test-utils.js';
 
 const Basics = suite('HMX Basics');
@@ -8,18 +9,14 @@ const Basics = suite('HMX Basics');
 let runtime;
 
 Basics.before(async () => {
-  const astroConfig = {
-    projectRoot: new URL('./fixtures/astro-basic/', import.meta.url),
-    hmxRoot: new URL('./fixtures/astro-basic/astro/', import.meta.url),
-    dist: './_site',
-  };
+  const astroConfig = await loadConfig(new URL('./fixtures/astro-basics', import.meta.url).pathname);
 
   const logging = {
     level: 'error',
     dest: process.stderr,
   };
 
-  runtime = await createRuntime(astroConfig, logging);
+  runtime = await createRuntime(astroConfig, {logging});
 });
 
 Basics.after(async () => {
diff --git a/test/astro-doctype.test.js b/test/astro-doctype.test.js
new file mode 100644
index 000000000..23188fd97
--- /dev/null
+++ b/test/astro-doctype.test.js
@@ -0,0 +1,54 @@
+import { suite } from 'uvu';
+import * as assert from 'uvu/assert';
+import { loadConfig } from '../lib/config.js';
+import { createRuntime } from '../lib/runtime.js';
+
+const DType = suite('doctype');
+
+let runtime, setupError;
+
+DType.before(async () => {
+  try {
+    const astroConfig = await loadConfig(new URL('./fixtures/astro-doctype', import.meta.url).pathname);
+
+    const logging = {
+      level: 'error',
+      dest: process.stderr,
+    };
+
+
+    runtime = await createRuntime(astroConfig, {logging});
+  } catch (err) {
+    console.error(err);
+    setupError = err;
+  }
+});
+
+DType.after(async () => {
+  (await runtime) && runtime.shutdown();
+});
+
+DType('No errors creating a runtime', () => {
+  assert.equal(setupError, undefined);
+});
+
+DType('Automatically prepends the standards mode doctype', async () => {
+  const result = await runtime.load('/prepend');
+
+  assert.equal(result.statusCode, 200);
+
+  const html = result.contents.toString('utf-8');
+  assert.ok(html.startsWith('<!doctype html>'), 'Doctype always included');
+});
+
+DType.skip('Preserves user provided doctype', async () => {
+  const result = await runtime.load('/preserve');
+
+  assert.equal(result.statusCode, 200);
+
+  const html = result.contents.toString('utf-8');
+  assert.ok(html.startsWith('<!doctype HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">'),
+    'Doctype included was preserved');
+});
+
+DType.run();
diff --git a/test/astro-markdown.test.js b/test/astro-markdown.test.js
index cbab25e36..7f5b310e3 100644
--- a/test/astro-markdown.test.js
+++ b/test/astro-markdown.test.js
@@ -17,7 +17,7 @@ Markdown.before(async () => {
   };
 
   try {
-    runtime = await createRuntime(astroConfig, logging);
+    runtime = await createRuntime(astroConfig, {logging});
   } catch (err) {
     console.error(err);
     setupError = err;
diff --git a/test/astro-styles-ssr.test.js b/test/astro-styles-ssr.test.js
index 69fa68353..27da41049 100644
--- a/test/astro-styles-ssr.test.js
+++ b/test/astro-styles-ssr.test.js
@@ -16,7 +16,7 @@ StylesSSR.before(async () => {
     dest: process.stderr,
   };
 
-  runtime = await createRuntime(astroConfig, logging);
+  runtime = await createRuntime(astroConfig, {logging});
 });
 
 StylesSSR.after(async () => {
diff --git a/test/fixtures/astro-doctype/astro.config.mjs b/test/fixtures/astro-doctype/astro.config.mjs
new file mode 100644
index 000000000..c7cbdb435
--- /dev/null
+++ b/test/fixtures/astro-doctype/astro.config.mjs
@@ -0,0 +1,5 @@
+export default {
+  projectRoot: '.',
+  astroRoot: './astro',
+  dist: './_site',
+};
diff --git a/test/fixtures/astro-doctype/astro/pages/prepend.astro b/test/fixtures/astro-doctype/astro/pages/prepend.astro
new file mode 100644
index 000000000..f8fb1bacd
--- /dev/null
+++ b/test/fixtures/astro-doctype/astro/pages/prepend.astro
@@ -0,0 +1,8 @@
+---
+let title = 'My Site';
+---
+
+<html lang="en">
+  <head><title>{title}</title></head>
+  <body><h1>Hello world</h1></body>
+</html>
\ No newline at end of file
diff --git a/test/fixtures/astro-doctype/astro/pages/preserve.astro b/test/fixtures/astro-doctype/astro/pages/preserve.astro
new file mode 100644
index 000000000..3e1ca934f
--- /dev/null
+++ b/test/fixtures/astro-doctype/astro/pages/preserve.astro
@@ -0,0 +1,9 @@
+---
+let title = 'My Site';
+---
+
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html lang="en">
+  <head><title>{title}</title></head>
+  <body><h1>Hello world</h1></body>
+</html>
\ No newline at end of file
diff --git a/test/react-component.test.js b/test/react-component.test.js
index 85892a623..48608f902 100644
--- a/test/react-component.test.js
+++ b/test/react-component.test.js
@@ -17,7 +17,7 @@ React.before(async () => {
   };
 
   try {
-    runtime = await createRuntime(astroConfig, logging);
+    runtime = await createRuntime(astroConfig, {logging});
   } catch (err) {
     console.error(err);
     setupError = err;
diff --git a/test/snowpack-integration.test.js b/test/snowpack-integration.test.js
index 097550d39..ba2c509c0 100644
--- a/test/snowpack-integration.test.js
+++ b/test/snowpack-integration.test.js
@@ -25,7 +25,7 @@ SnowpackDev.before(async () => {
   };
 
   try {
-    runtime = await createRuntime(astroConfig, logging);
+    runtime = await createRuntime(astroConfig, {logging});
   } catch (err) {
     console.error(err);
     setupError = err;
