diff --git a/CHANGELOG.md b/CHANGELOG.md
index 39676a3..0d39bfb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # rollup-plugin-typescript changelog
 
+## 0.2.1
+* Enable source maps per default
+
 ## 0.2.0
 * Use (_prerelease version of_) TypeScript 1.7.0 to generate ES5 while preserving ES2015 imports for efficient bundling.
 
diff --git a/index.js b/index.js
index 4a3af5c..229e385 100644
--- a/index.js
+++ b/index.js
@@ -1,4 +1,4 @@
-var typescript = require( 'typescript' );
+var ts = require( 'typescript' );
 var createFilter = require( 'rollup-pluginutils' ).createFilter;
 
 var assign = Object.assign || function ( target, source ) {
@@ -9,25 +9,57 @@ var assign = Object.assign || function ( target, source ) {
 	return target;
 };
 
-module.exports = function ( options ) {
+function goodErrors ( diagnostic ) {
+	// All errors except `Cannot compile modules into 'es6' when targeting 'ES5' or lower.`
+	return diagnostic.code !== 1204;
+}
+
+module.exports = function typescript ( options ) {
 	options = assign( {}, options || {} );
 
-	var filter = createFilter( options.include, options.exclude );
+	var filter = createFilter( options.include || [ '*.ts+(|x)', '**/*.ts+(|x)' ], options.exclude );
 	delete options.include;
 	delete options.exclude;
 
+	options = assign( {
+		target: ts.ScriptTarget.ES5,
+		module: ts.ModuleKind.ES6,
+		sourceMap: true
+	}, options );
+
 	return {
 		transform: function ( code, id ) {
 			if ( !filter( id ) ) return null;
 
-			var transformed = typescript.transpileModule( code, {
-				compilerOptions: assign( {
-					target: typescript.ScriptTarget.ES5,
-					module: typescript.ModuleKind.ES6,
-					sourceMap: true
-				}, options )
+			var transformed = ts.transpileModule( code, {
+				reportDiagnostics: true,
+				compilerOptions: options
+			});
+
+			var diagnostics = transformed.diagnostics.filter( goodErrors );
+			var fatalError = false;
+
+			diagnostics.forEach(function ( diagnostic ) {
+				var message = ts.flattenDiagnosticMessageText(diagnostic.messageText, '\n');
+
+				if ( diagnostic.file ) {
+					var pos = diagnostic.file.getLineAndCharacterOfPosition( diagnostic.start );
+
+					console.error( diagnostic.file.fileName +
+						'(' + (pos.line + 1) + ',' + (pos.character + 1) + '): error ES' +
+						diagnostic.code + ': ' + message );
+				} else {
+					console.error( 'Error: ' + message );
+				}
+
+				if ( diagnostic.category === ts.DiagnosticCategory.Error ) {
+					fatalError = true;
+				}
 			});
 
+			if ( fatalError ) {
+				throw new Error( 'There were TypeScript errors transpiling "' + id + '"' );
+			}
 
 			return {
 				code: transformed.outputText,
diff --git a/package.json b/package.json
index 9ff3cd0..2c8fcd2 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "rollup-plugin-typescript",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "description": "Seamless integration between Rollup and TypeScript.",
   "keywords": [
     "rollup-plugin",
diff --git a/test/sample/syntax-error/missing-type.ts b/test/sample/syntax-error/missing-type.ts
new file mode 100644
index 0000000..49d803c
--- /dev/null
+++ b/test/sample/syntax-error/missing-type.ts
@@ -0,0 +1 @@
+var a: ;
diff --git a/test/test.js b/test/test.js
index fc5dfb1..15f29a2 100644
--- a/test/test.js
+++ b/test/test.js
@@ -8,20 +8,13 @@ describe( 'rollup-plugin-typescript', function () {
 	this.timeout( 5000 );
 
 	it( 'runs code through typescript', function () {
-		var start = Date.now();
-
 		return rollup.rollup({
 			entry: 'sample/basic/main.ts',
 			plugins: [
 				typescript()
 			]
 		}).then( function ( bundle ) {
-			console.log( 'bundled in %s ms', Date.now() - start );
-
-			start = Date.now();
 			const generated = bundle.generate();
-			console.log( 'generated in %s ms', Date.now() - start );
-
 			const code = generated.code;
 
 			assert.ok( code.indexOf( 'number' ) === -1, code );
@@ -29,21 +22,14 @@ describe( 'rollup-plugin-typescript', function () {
 		});
 	});
 
-	it( 'transpiles ES6 features to ES5', function () {
-		var start = Date.now();
-
+	it( 'transpiles ES6 features to ES5 with source maps', function () {
 		return rollup.rollup({
 			entry: 'sample/import-class/main.ts',
 			plugins: [
 				typescript()
 			]
 		}).then( function ( bundle ) {
-			console.log( 'bundled in %s ms', Date.now() - start );
-
-			start = Date.now();
 			const generated = bundle.generate();
-			console.log( 'generated in %s ms', Date.now() - start );
-
 			const code = generated.code;
 
 			assert.ok( code.indexOf( 'class' ) === -1, code );
@@ -51,4 +37,15 @@ describe( 'rollup-plugin-typescript', function () {
 			assert.ok( code.indexOf( '=>' ) === -1, code );
 		});
 	});
+
+	it( 'reports diagnostics and throws if errors occur during transpilation', function () {
+		return rollup.rollup({
+			entry: 'sample/syntax-error/missing-type.ts',
+			plugins: [
+				typescript()
+			]
+		}).catch( function ( error ) {
+			assert.ok( error.message.indexOf( 'There were TypeScript errors' ) === 0, 'Should reject erroneous code.' );
+		});
+	});
 });