diff --git a/scripts/interface/Interface.js b/scripts/interface/Interface.js
index 069d811..be87d4c 100644
--- a/scripts/interface/Interface.js
+++ b/scripts/interface/Interface.js
@@ -28,6 +28,18 @@ define([
 		events.forEach((event) => element.addEventListener(event, fn));
 	}
 
+	function simplifyPreview(code) {
+		code = code.replace(/\{Agent([0-9]*)\}/g, (match, num) => {
+			if(num === undefined) {
+				return 'A';
+			} else {
+				return String.fromCharCode('A'.charCodeAt(0) + Number(num) - 1);
+			}
+		});
+		code = code.replace(/[{}]/g, '');
+		return code;
+	}
+
 	return class Interface {
 		constructor({
 			parser,
@@ -36,6 +48,7 @@ define([
 			exporter,
 			defaultCode = '',
 			localStorage = '',
+			library = null,
 		}) {
 			this.parser = parser;
 			this.generator = generator;
@@ -43,6 +56,7 @@ define([
 			this.exporter = exporter;
 			this.defaultCode = defaultCode;
 			this.localStorage = localStorage;
+			this.library = library;
 			this.minScale = 1.5;
 
 			this.debounced = null;
@@ -133,8 +147,8 @@ define([
 			code.on('endCompletion', () => {
 				lastKey = 0;
 			});
-			code.on('change', (cm) => {
-				if(cm.state.completionActive) {
+			code.on('change', (cm, change) => {
+				if(cm.state.completionActive || change.origin === 'library') {
 					return;
 				}
 				if(lastKey === 13 || lastKey === 8) {
@@ -193,12 +207,43 @@ define([
 			});
 		}
 
-		build(container) {
-			const codePane = makeNode('div', {'class': 'pane-code'});
-			const viewPane = makeNode('div', {'class': 'pane-view'});
-			this.errorPane = makeNode('div', {'class': 'pane-error'});
+		buildLibrary(container) {
+			this.library.forEach((lib) => {
+				const hold = makeNode('div', {
+					'class': 'library-item',
+				});
+				const holdInner = makeNode('div', {
+					'title': lib.title || lib.code,
+				});
+				hold.appendChild(holdInner);
+				hold.addEventListener(
+					'click',
+					this.addCodeBlock.bind(this, lib.code)
+				);
+				container.appendChild(hold);
+				try {
+					const preview = simplifyPreview(lib.preview || lib.code);
+					const parsed = this.parser.parse(preview);
+					const generated = this.generator.generate(parsed);
+					const rendering = this.renderer.clone();
+					holdInner.appendChild(rendering.svg());
+					rendering.render(generated);
+				} catch(e) {
+					hold.setAttribute('class', 'library-item broken');
+					holdInner.appendChild(makeText(lib.code));
+				}
+			});
+		}
+
+		buildErrorReport() {
+			this.errorMsg = makeNode('div', {'class': 'msg-error'});
 			this.errorText = makeText();
-			this.errorPane.appendChild(this.errorText);
+			this.errorMsg.appendChild(this.errorText);
+			return this.errorMsg;
+		}
+
+		buildViewPane() {
+			const viewPane = makeNode('div', {'class': 'pane-view'});
 			const viewPaneScroller = makeNode('div', {
 				'class': 'pane-view-scroller',
 			});
@@ -210,10 +255,31 @@ define([
 			viewPaneScroller.appendChild(this.viewPaneInner);
 			viewPane.appendChild(this.buildOptionsLinks());
 			viewPane.appendChild(this.buildOptionsDownloads());
+			viewPane.appendChild(this.buildErrorReport());
 
+			return viewPane;
+		}
+
+		build(container) {
+			const codePane = makeNode('div', {'class': 'pane-code'});
 			container.appendChild(codePane);
-			container.appendChild(this.errorPane);
-			container.appendChild(viewPane);
+
+			if(this.library !== null) {
+				const libPane = makeNode('div', {'class': 'pane-library'});
+				const libPaneScroller = makeNode('div', {
+					'class': 'pane-library-scroller',
+				});
+				const libPaneInner = makeNode('div', {
+					'class': 'pane-library-inner',
+				});
+				libPaneScroller.appendChild(libPaneInner);
+				libPane.appendChild(libPaneScroller);
+				container.appendChild(libPane);
+				codePane.setAttribute('class', 'pane-code reduced');
+				this.buildLibrary(libPaneInner);
+			}
+
+			container.appendChild(this.buildViewPane());
 
 			this.code = this.buildEditor(codePane);
 			this.viewPaneInner.appendChild(this.renderer.svg());
@@ -222,6 +288,20 @@ define([
 			this.update();
 		}
 
+		addCodeBlock(block) {
+			const cur = this.code.getCursor('head');
+			const pos = {line: cur.line + ((cur.ch > 0) ? 1 : 0), ch: 0};
+			const lines = block.split('\n').length;
+			this.code.replaceRange(
+				block + '\n',
+				pos,
+				null,
+				'library'
+			);
+			this.code.setCursor({line: pos.line + lines, ch: 0});
+			this.code.focus();
+		}
+
 		updateMinSize(width, height) {
 			const style = this.viewPaneInner.style;
 			style.minWidth = Math.ceil(width * this.minScale) + 'px';
@@ -265,12 +345,12 @@ define([
 			} else {
 				this.errorText.nodeValue = error;
 			}
-			this.errorPane.setAttribute('class', 'pane-error error');
+			this.errorMsg.setAttribute('class', 'msg-error error');
 		}
 
 		markOK() {
-			this.errorText.nodeValue = 'All OK';
-			this.errorPane.setAttribute('class', 'pane-error ok');
+			this.errorText.nodeValue = '';
+			this.errorMsg.setAttribute('class', 'msg-error');
 		}
 
 		update(immediate = true) {
diff --git a/scripts/main.js b/scripts/main.js
index ff3af1d..cc4661d 100644
--- a/scripts/main.js
+++ b/scripts/main.js
@@ -40,6 +40,156 @@
 			'\n' +
 			'terminators box\n'
 		);
+		const library = [
+			{
+				title: 'Simple arrow',
+				code: '{Agent1} -> {Agent2}: {Message}',
+			},
+			{
+				title: 'Arrow with dotted line',
+				code: '{Agent1} --> {Agent2}: {Message}',
+			},
+			{
+				title: 'Open arrow',
+				code: '{Agent1} ->> {Agent2}: {Message}',
+			},
+			{
+				title: 'Self-connection',
+				code: '{Agent1} -> {Agent1}: {Message}',
+			},
+			{
+				title: 'Request/response pair',
+				code: (
+					'{Agent1} -> +{Agent2}: {Request}\n' +
+					'{Agent1} <-- -{Agent2}: {Response}'
+				),
+			},
+			{
+				title: 'Inline agent creation / destruction',
+				code: (
+					'{Agent1} -> *{Agent2}: {Request}\n' +
+					'{Agent1} <-- !{Agent2}: {Response}'
+				),
+			},
+			{
+				title: 'Agent creation / destruction',
+				code: (
+					'{Agent1} -> {Agent2}: {Request}\n' +
+					'{Agent1} <-- {Agent2}: {Response}\n' +
+					'end {Agent2}'
+				),
+				preview: (
+					'begin A\n' +
+					'::\n' +
+					'A -> B: Request\n' +
+					'A <-- B: Response\n' +
+					'end B'
+				),
+			},
+			{
+				title: 'Conditional blocks',
+				code: (
+					'if {Condition1}\n' +
+					'  {Agent1} -> {Agent2}\n' +
+					'else if {Condition2}\n' +
+					'  {Agent1} -> {Agent2}\n' +
+					'else\n' +
+					'  {Agent1} -> {Agent2}\n' +
+					'end'
+				),
+				preview: (
+					'begin A, B\n' +
+					'if Condition1\n' +
+					'  A -> B\n' +
+					'else if Condition2\n' +
+					'  A -> B\n' +
+					'else\n' +
+					'  A -> B\n' +
+					'end'
+				),
+			},
+			{
+				title: 'Repeated blocks',
+				code: (
+					'repeat {Condition}\n' +
+					'  {Agent1} -> {Agent2}\n' +
+					'end'
+				),
+				preview: (
+					'begin A, B\n' +
+					'repeat Condition\n' +
+					'  A -> B\n' +
+					'end'
+				),
+			},
+			{
+				title: 'Note over agent',
+				code: 'note over {Agent1}: {Message}',
+			},
+			{
+				title: 'Note over multiple agents',
+				code: 'note over {Agent1}, {Agent2}: {Message}',
+			},
+			{
+				title: 'Note left of agent',
+				code: 'note left of {Agent1}: {Message}',
+			},
+			{
+				title: 'Note right of agent',
+				code: 'note right of {Agent1}: {Message}',
+			},
+			{
+				title: 'Note between agents',
+				code: 'note between {Agent1}, {Agent2}: {Message}',
+			},
+			{
+				title: 'State over agent',
+				code: 'state over {Agent1}: {State}',
+			},
+			{
+				title: 'Arrows to/from the sides',
+				code: '[ -> {Agent1}: {Message1}\n{Agent1} -> ]: {Message2}',
+			},
+			{
+				title: 'Text beside the diagram',
+				code: 'text right: {Message}',
+				preview: (
+					'A -> B\n' +
+					'simultaneously:\n' +
+					'text right: "Message\\non the\\nside"'
+				),
+			},
+			{
+				title: 'Title',
+				code: 'title {Title}',
+				preview: 'title Title\nA -> B',
+			},
+			{
+				title: 'Chunky theme',
+				code: 'theme chunky',
+				preview: 'theme chunky\nA -> B',
+			},
+			{
+				title: 'Cross terminators',
+				code: 'terminators cross',
+				preview: 'A -> B\nterminators cross',
+			},
+			{
+				title: 'Fade terminators',
+				code: 'terminators fade',
+				preview: 'A -> B\nterminators fade',
+			},
+			{
+				title: 'Bar terminators',
+				code: 'terminators bar',
+				preview: 'A -> B\nterminators bar',
+			},
+			{
+				title: 'Box terminators',
+				code: 'terminators box',
+				preview: 'A -> B\nterminators box',
+			},
+		];
 		const ui = new Interface({
 			defaultCode,
 			parser: new Parser(),
@@ -49,6 +199,7 @@
 				new ChunkyTheme(),
 			]}),
 			exporter: new Exporter(),
+			library,
 			localStorage: 'src',
 		});
 		ui.build(document.body);
diff --git a/scripts/sequence/Renderer.js b/scripts/sequence/Renderer.js
index bc2b1df..d624e74 100644
--- a/scripts/sequence/Renderer.js
+++ b/scripts/sequence/Renderer.js
@@ -135,6 +135,15 @@ define([
 			});
 		}
 
+		clone({namespace = null} = {}) {
+			return new Renderer({
+				themes: this.getThemes(),
+				namespace,
+				components: this.components,
+				SVGTextBlockClass: this.SVGTextBlockClass,
+			});
+		}
+
 		buildStaticElements() {
 			this.base = svg.makeContainer();
 
@@ -625,6 +634,10 @@ define([
 			);
 		}
 
+		getThemes() {
+			return this.getThemeNames().map((name) => this.themes.get(name));
+		}
+
 		getAgentX(name) {
 			return this.agentInfos.get(name).x;
 		}
diff --git a/styles/main.css b/styles/main.css
index 8e32757..179b6f3 100644
--- a/styles/main.css
+++ b/styles/main.css
@@ -7,12 +7,16 @@ html, body {
 	position: absolute;
 	left: 0;
 	top: 0;
-	bottom: 100px;
+	bottom: 0;
 	width: 30%;
 	box-sizing: border-box;
 	border-right: 1px solid #808080;
 }
 
+.pane-code.reduced {
+	bottom: 200px;
+}
+
 .pane-code .CodeMirror {
 	width: 100%;
 	height: 100%;
@@ -67,29 +71,88 @@ html, body {
 	height: 100%;
 }
 
-.pane-error {
+.pane-library {
 	position: absolute;
 	left: 0;
 	bottom: 0;
 	width: 30%;
+	height: 200px;
+	box-sizing: border-box;
+	background: #EEEEEE;
+	border-top: 1px solid #808080;
+	border-right: 1px solid #808080;
+	user-select: none;
+}
+
+.pane-library-scroller {
+	width: 100%;
+	height: 100%;
+	overflow: auto;
+}
+
+.pane-library-inner {
+	padding: 5px;
+}
+
+.library-item {
+	display: inline-block;
+	width: 80px;
+	height: 80px;
+}
+
+.library-item > div {
+	width: 80px;
+	height: 80px;
+	border: 2px solid #EEEEEE;
+	background: #FFFFFF;
+	box-sizing: border-box;
+	cursor: pointer;
+	overflow: hidden;
+	transition: transform 0.2s, border-color 0.2s, background 0.2s;
+}
+
+.library-item.broken > div {
+	padding: 5px;
+	font: 6px monospace;
+	white-space: pre;
+}
+
+.library-item svg {
+	width: 100%;
+	height: 100%;
+}
+
+.library-item:hover > div {
+	border-color: #FFCC00;
+	background: #FFFFDD;
+/*	position: absolute;*/
+	transform: scale(1.1);
+	z-index: 10;
+}
+
+.msg-error {
+	display: none;
+	position: absolute;
+	top: 50%;
+	left: 20%;
+	margin-top: -50px;
+	width: 60%;
 	height: 100px;
 	overflow: auto;
 	box-sizing: border-box;
 	padding: 5px 10px;
 	font-family: monospace;
-	background: #DDDDDD;
-	border-top: 1px solid #808080;
-	border-right: 1px solid #808080;
-}
-
-.pane-error.ok {
-	color: #007700;
-	background: #E8EEE8;
-}
-
-.pane-error.error {
 	color: #770000;
 	background: #EEE8E8;
+	border: 1px solid rgba(0, 0, 0, 0.5);
+	border-radius: 5px;
+	box-shadow: 0 0 30px rgba(0, 0, 0, 0.2);
+	opacity: 0.95;
+	z-index: 4;
+}
+
+.msg-error.error {
+	display: block;
 }
 
 .options {