diff --git a/src/classes/RefTest.js b/src/classes/RefTest.js
new file mode 100644
index 0000000..ff46335
--- /dev/null
+++ b/src/classes/RefTest.js
@@ -0,0 +1,315 @@
+import { doClick, create, $$, bind, ready } from "../dom.js";
+import { formatDuration } from "../util.js";
+import hooks from "../hooks.js";
+import * as compare from "../compare.js";
+
+export default class RefTest {
+	constructor (table) {
+		this.table = table;
+		table.reftest = this;
+		this.columns =
+			+this.table.getAttribute("data-columns") ||
+			Math.max.apply(
+				Math,
+				[...this.table.rows].map(row => row.cells.length),
+			);
+		this.manual = this.table.matches(".manual");
+		this.init();
+	}
+
+	async init () {
+		this.compare = this.manual
+			? null
+			: await RefTest.getTest(this.table.getAttribute("data-test"));
+		this.setup();
+
+		if (!this.manual) {
+			this.startup = performance.now();
+			this.test();
+		}
+	}
+
+	setup () {
+		if (this.table.rows.length === 0) {
+			console.warn("Empty reftest:", this.table);
+			return;
+		}
+
+		// Add table header if not present
+		if (!this.table.querySelector("thead") && this.columns > 1) {
+			var header = [
+				...Array(Math.max(0, this.columns - 2)).fill("Test"),
+				"Actual",
+				"Expected",
+			].slice(-this.columns);
+
+			create("thead", {
+				contents: [
+					{
+						tag: "tr",
+						contents: header.map(text => {
+							return { tag: "th", textContent: text };
+						}),
+					},
+				],
+				start: this.table,
+			});
+		}
+
+		// Observe class changes on <tr>s and update the results
+		this.resultObserver = new MutationObserver(mutation => {
+			for (let { target } of mutation) {
+				if (target.matches("tr")) {
+					RefTest.updateResults();
+				}
+			}
+		});
+
+		this.resultObserver.observe(this.table, {
+			subtree: true,
+			attributes: true,
+			attributeFilter: ["class"],
+		});
+
+		if (!this.manual) {
+			let test = x => {
+				requestAnimationFrame(() => this.test());
+			};
+
+			this.observer = new MutationObserver(test);
+			this.observe();
+
+			bind(this.table, "input change click", test);
+
+			$$("[data-click]", this.table)
+				.concat(this.table.matches("[data-click]") ? [this.table] : [])
+				.forEach(target => {
+					target
+						.getAttribute("data-click")
+						.trim()
+						.split(/\s*,\s*/)
+						.forEach(click => doClick(click, target));
+				});
+		}
+
+		ready().then(() => RefTest.updateResults());
+	}
+
+	observe () {
+		this.observerRunning = true;
+
+		this.observer.observe(this.table, {
+			subtree: true,
+			childList: true,
+			attributes: true,
+			characterData: true,
+		});
+	}
+
+	unobserve () {
+		this.observer.disconnect();
+		this.observerRunning = false;
+	}
+
+	// Run code past observer
+	sneak (callback) {
+		this.unobserve();
+		var ret = callback.call(this);
+		this.observe();
+		return ret;
+	}
+
+	test () {
+		hooks.run("reftest-test", this);
+
+		for (let tr of this.table.rows) {
+			if (!this.table.tHead || tr !== this.table.tHead.rows[0]) {
+				this.testRow(tr);
+			}
+		}
+	}
+
+	async testRow (tr) {
+		let env = { context: this, tr, cells: [...tr.cells] };
+		hooks.run("reftest-testrow", env);
+
+		if (!env.tr.compare) {
+			env.tr.compare = await RefTest.getTest(env.tr.getAttribute("data-test"), this.compare);
+		}
+
+		let resultCell = env.tr.cells[env.tr.cells.length - 1];
+
+		if (env.cells.length) {
+			if (this.columns == 3) {
+				// Test, actual, expected
+				if (env.cells.length == 1) {
+					// expected is the same as test
+					resultCell = create("td", { after: env.cells[0] });
+					env.cells.push(resultCell);
+				}
+
+				if (env.cells.length == 2) {
+					// missing actual
+					resultCell = create("td", { after: env.cells[0] });
+					env.cells.splice(1, 0, resultCell);
+				}
+
+				if (!env.cells[2].textContent) {
+					env.cells[2].textContent = env.cells[0].textContent;
+				}
+			}
+			else if (this.columns == 2 && !env.cells[0].innerHTML) {
+				// Empty cell, takes the test from above
+				let previous = env.tr;
+				while ((previous = previous.previousElementSibling)) {
+					if (previous.cells[0].innerHTML) {
+						env.cells[0] = previous.cells[0];
+						break;
+					}
+				}
+			}
+
+			try {
+				var ret = this.sneak(() => tr.compare(...env.cells));
+				resultCell.onclick = null;
+			}
+			catch (e) {
+				ret = e;
+				var error = true;
+				resultCell.textContent = e + "";
+				resultCell.onclick = evt => console.error(e);
+			}
+
+			var error = ret instanceof Error;
+
+			var previousClass = tr.classList.contains("pass") ? "pass" : "fail";
+			tr.classList.remove("pass", "fail");
+			let pass = ret;
+			if (error) {
+				pass = tr.hasAttribute("data-error");
+			}
+
+			var className = pass ? "pass" : "fail";
+			tr.classList.add(className);
+
+			if (
+				className == "pass" &&
+				className != previousClass &&
+				!tr.classList.contains("interactive")
+			) {
+				// Display how long it took
+				let time = performance.now() - this.startup;
+				tr.setAttribute("data-time", formatDuration(time));
+			}
+		}
+	}
+
+	static hooks = hooks;
+
+	// Retrieve the comparator function based on a data-test string
+	static async getTest (test, fallback) {
+		if (test) {
+			if (test in this.compare) {
+				return this.compare[test];
+			}
+			else {
+				if (test in globalThis) {
+					return globalThis[test];
+				}
+				else {
+					// return new Function("td", "ref", test);
+					// Try again in a bit
+					await new Promise(resolve =>
+						window.addEventListener("load", resolve, { once: true }));
+					return globalThis[test];
+				}
+			}
+		}
+
+		return fallback || RefTest.compare.contents;
+	}
+
+	// Default comparison functions
+	static compare = compare;
+
+	// Prettify code for presentation
+	// TODO just use Prism whitespace plugin
+	static presentCode (code) {
+		// Remove blank line in the beginning and end
+		code = code.replace(/^\s*\n|\n\s*$/g, "");
+
+		// Remove extra indentation
+		var indent = (code.match(/^\s*/) || [""])[0];
+		code = code.replace(RegExp("^" + indent, "gm"), "");
+
+		code = code.replace(/document.write/g, "print");
+
+		return code;
+	}
+
+	static updateResults () {
+		this.results = {
+			pass: $$("table.reftest:not(.skipped) tr.pass:not(.skipped)"),
+			fail: $$("table.reftest:not(.skipped) tr.fail:not(.skipped)"),
+			skipped: $$("table.reftest tr.skipped"),
+			current: {
+				pass: -1,
+				fail: -1,
+				skipped: -1,
+			},
+			// interactive: $$("table.reftest tr.interactive")
+		};
+
+		let detail = {
+			pass: this.results.pass.length,
+			fail: this.results.fail.length,
+			skipped: this.results.skipped.length,
+		};
+
+		document.body.style.setProperty("--pass", detail.pass);
+		document.body.style.setProperty("--fail", detail.fail);
+		document.body.style.setProperty("--skipped", detail.skipped);
+
+		document.body.classList.toggle("no-passed", detail.pass === 0);
+		document.body.classList.toggle("no-failed", detail.fail === 0);
+		document.body.classList.toggle("no-skipped", detail.skipped === 0);
+		// $(".count-interactive", RefTest.nav).textContent = RefTest.results.interactive.length;
+
+		document.dispatchEvent(new CustomEvent("testresultsupdate", { detail }));
+	}
+
+	// Navigate tests
+	static #navigateTests (type = "fail", offset) {
+		let elements = this.results[type];
+		let i = this.results.current[type] + offset;
+
+		if (!elements.length) {
+			return;
+		}
+
+		if (i >= elements.length) {
+			i = 0;
+		}
+		else if (i < 0) {
+			i = elements.length - 1;
+		}
+
+		if (elements.length > 1) {
+			let countElement = RefTest.nav.querySelector(".count-" + type);
+			countElement.querySelector(".nav").hidden = false;
+			countElement.querySelector(".current").textContent = i + 1;
+		}
+
+		elements[i].scrollIntoView({ behavior: "smooth" });
+
+		this.results.current[type] = i;
+	}
+
+	static next (type = "fail") {
+		this.#navigateTests(type, 1);
+	}
+
+	static previous (type = "fail") {
+		this.#navigateTests(type, -1);
+	}
+}
diff --git a/src/dom.js b/src/dom.js
new file mode 100644
index 0000000..329441d
--- /dev/null
+++ b/src/dom.js
@@ -0,0 +1,91 @@
+import { delay, getType, stringify } from "./util.js";
+export { default as create } from "https://v2.blissfuljs.com/src/dom/create.js";
+export { default as bind } from "https://v2.blissfuljs.com/src/events/bind.js";
+export { default as include } from "https://v2.blissfuljs.com/src/async/include.js";
+
+/**
+ * Parse data-click text into a meaningful structure.
+ * @example
+ * .foo .bar wait 5s after load
+ * @example
+ * .foo .bar wait 3s (no event, DOMContentLoaded assumed)
+ * @example
+ * wait 1s after load (no selector, element assumed)
+ */
+export function parseClick (click) {
+	var ret = { times: 1 };
+
+	click = click.replace(/wait ([\d.]+)s/i, ($0, $1) => {
+		ret.delay = $1 * 1000;
+		return "";
+	});
+
+	click = click.replace(/after ([\w:-]+)\s*$/i, ($0, $1) => {
+		ret.event = $1;
+		return "";
+	});
+
+	click = click.replace(/(\d+) times/i, ($0, $1) => {
+		ret.times = $1;
+		return "";
+	});
+
+	ret.selector = click.trim();
+
+	return ret;
+}
+
+export async function doClick (click, target) {
+	click = parseClick(click);
+
+	if (click.event) {
+		await new Promise(resolve => target.addEventListener(click.event, resolve, { once: true }));
+	}
+
+	if (click.delay) {
+		await delay(click.delay);
+	}
+
+	let targets = click.selector ? $$(click.selector, target) : [target];
+
+	for (let target of targets) {
+		for (let i = 0; i < click.times; i++) {
+			target.click();
+		}
+	}
+}
+
+export function $$ (selector, context = document) {
+	return [...context.querySelectorAll(selector)];
+}
+
+export function ready (doc = document) {
+	return new Promise(resolve => {
+		if (doc.readyState !== "loading") {
+			resolve();
+		}
+		else {
+			doc.addEventListener("DOMContentLoaded", resolve, { once: true });
+		}
+	});
+}
+
+export function output (obj) {
+	return stringify(obj, {
+		custom: obj => {
+			if (Array.isArray(obj)) {
+				return obj.map(output).join(", ");
+			}
+
+			if (typeof obj === "string") {
+				return obj;
+			}
+
+			// Handle nested objects
+			if (obj && typeof obj === "object") {
+				let entries = Object.entries(obj).map(([key, value]) => `${key}: ${output(value)}`);
+				return "{ " + entries.join(", ") + " }";
+			}
+		},
+	});
+}
diff --git a/src/render.js b/src/render.js
index f44be94..302a291 100644
--- a/src/render.js
+++ b/src/render.js
@@ -4,8 +4,8 @@
 
 import Test from "./classes/Test.js";
 import TestResult from "./classes/TestResult.js";
-import RefTest from "https://html.htest.dev/src/classes/RefTest.js";
-import { create, output } from "https://html.htest.dev/src/util.js";
+import RefTest from "./classes/RefTest.js";
+import { create, output } from "./dom.js";
 import { formatDuration } from "./util.js";
 import format from "./format-console.js";