diff --git a/src/Stats.ts b/src/Stats.ts
index 7653d6e303..ea378bcaeb 100644
--- a/src/Stats.ts
+++ b/src/Stats.ts
@@ -108,7 +108,7 @@ export default class Stats {
 			timings,
 			warnings: this.warnings,
 			imports,
-			templateReferences: component && component.expectedProperties,
+			templateReferences: component && component.template_references,
 			hooks
 		};
 	}
diff --git a/src/compile/Component.ts b/src/compile/Component.ts
index c603ae047b..22e8a6ac1e 100644
--- a/src/compile/Component.ts
+++ b/src/compile/Component.ts
@@ -59,8 +59,7 @@ export default class Component {
 	instance_scope_map: WeakMap<Node, Scope>;
 
 	meta: Meta;
-
-	customElement: CustomElementOptions;
+	namespace: string;
 	tag: string;
 
 	properties: Map<string, Node>;
@@ -69,7 +68,6 @@ export default class Component {
 	module_script: Node;
 
 	imports: Node[] = [];
-	namespace: string;
 	hasComponents: boolean;
 	module_javascript: string;
 	javascript: string;
@@ -86,7 +84,7 @@ export default class Component {
 	code: MagicString;
 
 	indirectDependencies: Map<string, Set<string>> = new Map();
-	expectedProperties: Set<string> = new Set();
+	template_references: Set<string> = new Set();
 	refs: Set<string> = new Set();
 
 	file: string;
@@ -141,28 +139,25 @@ export default class Component {
 		this.meta = process_meta(this, this.ast.html.children);
 		this.namespace = namespaces[this.meta.namespace] || this.meta.namespace;
 
-		if (options.customElement === true) {
-			this.customElement = {
-				tag: this.meta.tag,
-				props: [] // TODO!!!
-			};
-		} else {
-			this.customElement = options.customElement;
-		}
-
-		if (this.customElement && !this.customElement.tag) {
+		if (options.customElement === true && !this.meta.tag) {
 			throw new Error(`No tag name specified`); // TODO better error
 		}
 
+		this.tag = options.customElement
+			? options.customElement === true
+				? this.meta.tag
+				: <string>options.customElement
+			: this.name;
+
 		this.fragment = new Fragment(this, ast.html);
-		if (!this.customElement) this.stylesheet.reify();
+		if (!options.customElement) this.stylesheet.reify();
 
 		this.stylesheet.warnOnUnusedSelectors(options.onwarn);
 
 		if (!this.instance_script) {
-			const props = [...this.expectedProperties];
+			const props = [...this.template_references];
 			this.declarations.push(...props);
-			addToSet(this.writable_declarations, this.expectedProperties);
+			addToSet(this.writable_declarations, this.template_references);
 
 			this.exports = props.map(name => ({
 				name,
@@ -270,7 +265,7 @@ export default class Component {
 
 		addString(finalChunk);
 
-		const css = this.customElement ?
+		const css = options.customElement ?
 			{ code: null, map: null } :
 			this.stylesheet.render(options.cssOutputFilename, true);
 
diff --git a/src/compile/nodes/InlineComponent.ts b/src/compile/nodes/InlineComponent.ts
index 32f1425059..017b28afd1 100644
--- a/src/compile/nodes/InlineComponent.ts
+++ b/src/compile/nodes/InlineComponent.ts
@@ -22,7 +22,7 @@ export default class InlineComponent extends Node {
 
 		if (info.name !== 'svelte:component' && info.name !== 'svelte:self') {
 			component.warn_if_undefined(info, scope);
-			component.expectedProperties.add(info.name);
+			component.template_references.add(info.name);
 		}
 
 		component.hasComponents = true;
diff --git a/src/compile/nodes/shared/Expression.ts b/src/compile/nodes/shared/Expression.ts
index 0bb524ff35..80bc89a678 100644
--- a/src/compile/nodes/shared/Expression.ts
+++ b/src/compile/nodes/shared/Expression.ts
@@ -137,7 +137,7 @@ export default class Expression {
 						});
 					} else {
 						dependencies.add(name);
-						component.expectedProperties.add(name);
+						component.template_references.add(name);
 					}
 
 					this.skip();
@@ -216,7 +216,7 @@ export default class Expression {
 							});
 						} else {
 							dependencies.add(name);
-							component.expectedProperties.add(name);
+							component.template_references.add(name);
 						}
 					} else if (!is_synthetic) {
 						code.prependRight(node.start, key === 'key' && parent.shorthand
diff --git a/src/compile/render-dom/index.ts b/src/compile/render-dom/index.ts
index f2c46a31ea..09564f0a84 100644
--- a/src/compile/render-dom/index.ts
+++ b/src/compile/render-dom/index.ts
@@ -27,12 +27,12 @@ export default function dom(
 		builder.addLine(`const ${renderer.fileVar} = ${JSON.stringify(component.file)};`);
 	}
 
-	const css = component.stylesheet.render(options.filename, !component.customElement);
+	const css = component.stylesheet.render(options.filename, !options.customElement);
 	const styles = component.stylesheet.hasStyles && stringify(options.dev ?
 		`${css.code}\n/*# sourceMappingURL=${css.map.toUrl()} */` :
 		css.code, { onlyEscapeAtSymbol: true });
 
-	if (styles && component.options.css !== false && !component.customElement) {
+	if (styles && component.options.css !== false && !options.customElement) {
 		builder.addBlock(deindent`
 			function @add_css() {
 				var style = @createElement("style");
@@ -64,7 +64,7 @@ export default function dom(
 	// TODO injecting CSS this way is kinda dirty. Maybe it should be an
 	// explicit opt-in, or something?
 	const should_add_css = (
-		!component.options.customElement &&
+		!options.customElement &&
 		component.stylesheet.hasStyles &&
 		options.css !== false
 	);
@@ -95,7 +95,6 @@ export default function dom(
 
 	const body = [];
 
-	const debug_name = `<${component.customElement ? component.customElement.tag : name}>`;
 	const not_equal = component.options.immutable ? `@not_equal` : `@safe_not_equal`;
 	let dev_props_check;
 
@@ -116,7 +115,7 @@ export default function dom(
 		} else if (component.options.dev) {
 			body.push(deindent`
 				set ${x.as}(value) {
-					throw new Error("${debug_name}: Cannot set read-only property '${x.as}'");
+					throw new Error("<${component.tag}>: Cannot set read-only property '${x.as}'");
 				}
 			`);
 		}
@@ -134,8 +133,8 @@ export default function dom(
 				const state = this.$$.get();
 				${expected.map(name => deindent`
 
-				if (state.${name} === undefined${component.customElement && ` && !('${name}' in this.attributes)`}) {
-					console.warn("${debug_name} was created without expected data property '${name}'");
+				if (state.${name} === undefined${options.customElement && ` && !('${name}' in this.attributes)`}) {
+					console.warn("<${component.tag}> was created without expected data property '${name}'");
 				}`)}
 			`;
 		}
@@ -195,7 +194,7 @@ export default function dom(
 		}
 	`);
 
-	if (component.customElement) {
+	if (options.customElement) {
 		builder.addBlock(deindent`
 			class ${name} extends @SvelteElement {
 				constructor(options) {
@@ -226,7 +225,7 @@ export default function dom(
 				${body.join('\n\n')}
 			}
 
-			customElements.define("${component.customElement.tag}", ${name});
+			customElements.define("${component.tag}", ${name});
 		`);
 	} else {
 		builder.addBlock(deindent`
diff --git a/src/compile/render-ssr/index.ts b/src/compile/render-ssr/index.ts
index 95f028574d..ffe2f24fb4 100644
--- a/src/compile/render-ssr/index.ts
+++ b/src/compile/render-ssr/index.ts
@@ -1,9 +1,7 @@
 import deindent from '../../utils/deindent';
 import Component from '../Component';
-import globalWhitelist from '../../utils/globalWhitelist';
 import { CompileOptions } from '../../interfaces';
 import { stringify } from '../../utils/stringify';
-import CodeBuilder from '../../utils/CodeBuilder';
 import Renderer from './Renderer';
 
 export default function ssr(
@@ -19,13 +17,10 @@ export default function ssr(
 		locate: component.locate
 	}, options));
 
-	const css = component.customElement ?
+	const css = options.customElement ?
 		{ code: null, map: null } :
 		component.stylesheet.render(options.filename, true);
 
-	const expectedProperties = Array.from(component.expectedProperties);
-	const debugName = `<${component.customElement ? component.tag : name}>`;
-
 	// TODO concatenate CSS maps
 	return (deindent`
 		function #define($$props) {