diff --git a/lib/katex/katex.js b/lib/katex/katex.js
new file mode 100644
index 0000000..664eb91
--- /dev/null
+++ b/lib/katex/katex.js
@@ -0,0 +1,225 @@
+//
+/* eslint no-console:0 */
+/**
+ * This is the main entry point for KaTeX. Here, we expose functions for
+ * rendering expressions either to DOM nodes or to markup strings.
+ *
+ * We also expose the ParseError class to check if errors thrown from KaTeX are
+ * errors in the expression, or errors in javascript handling.
+ */
+
+import ParseError from "./src/ParseError";
+import Settings, {SETTINGS_SCHEMA} from "./src/Settings";
+
+import {buildTree, buildHTMLTree} from "./src/buildTree";
+import parseTree from "./src/parseTree";
+import buildCommon from "./src/buildCommon";
+import {
+    Span,
+    Anchor,
+    SymbolNode,
+    SvgNode,
+    PathNode,
+    LineNode,
+} from "./src/domTree";
+
+
+
+
+
+import {defineSymbol} from './src/symbols';
+import defineFunction from './src/defineFunction';
+import defineMacro from './src/defineMacro';
+import {setFontMetrics} from './src/fontMetrics';
+
+
+
+/**
+ * Parse and build an expression, and place that expression in the DOM node
+ * given.
+ */
+let render                                          = function(
+    expression        ,
+    baseNode      ,
+    options                 ,
+) {
+    baseNode.textContent = "";
+    const node = renderToDomTree(expression, options).toNode();
+    baseNode.appendChild(node);
+};
+
+// KaTeX's styles don't work properly in quirks mode. Print out an error, and
+// disable rendering.
+if (typeof document !== "undefined") {
+    if (document.compatMode !== "CSS1Compat") {
+        typeof console !== "undefined" && console.warn(
+            "Warning: KaTeX doesn't work in quirks mode. Make sure your " +
+                "website has a suitable doctype.");
+
+        render = function() {
+            throw new ParseError("KaTeX doesn't work in quirks mode.");
+        };
+    }
+}
+
+/**
+ * Parse and build an expression, and return the markup for that.
+ */
+const renderToString = function(
+    expression        ,
+    options                 ,
+)         {
+    const markup = renderToDomTree(expression, options).toMarkup();
+    return markup;
+};
+
+/**
+ * Parse an expression and return the parse tree.
+ */
+const generateParseTree = function(
+    expression        ,
+    options                 ,
+)                 {
+    const settings = new Settings(options);
+    return parseTree(expression, settings);
+};
+
+/**
+ * If the given error is a KaTeX ParseError and options.throwOnError is false,
+ * renders the invalid LaTeX as a span with hover title giving the KaTeX
+ * error message.  Otherwise, simply throws the error.
+ */
+const renderError = function(
+    error,
+    expression        ,
+    options          ,
+) {
+    if (options.throwOnError || !(error instanceof ParseError)) {
+        throw error;
+    }
+    const node = buildCommon.makeSpan(["katex-error"],
+        [new SymbolNode(expression)]);
+    node.setAttribute("title", error.toString());
+    node.setAttribute("style", `color:${options.errorColor}`);
+    return node;
+};
+
+/**
+ * Generates and returns the katex build tree. This is used for advanced
+ * use cases (like rendering to custom output).
+ */
+const renderToDomTree = function(
+    expression        ,
+    options                 ,
+)          {
+    const settings = new Settings(options);
+    try {
+        const tree = parseTree(expression, settings);
+        return buildTree(tree, expression, settings);
+    } catch (error) {
+        return renderError(error, expression, settings);
+    }
+};
+
+/**
+ * Generates and returns the katex build tree, with just HTML (no MathML).
+ * This is used for advanced use cases (like rendering to custom output).
+ */
+const renderToHTMLTree = function(
+    expression        ,
+    options                 ,
+)          {
+    const settings = new Settings(options);
+    try {
+        const tree = parseTree(expression, settings);
+        return buildHTMLTree(tree, expression, settings);
+    } catch (error) {
+        return renderError(error, expression, settings);
+    }
+};
+
+export default {
+    /**
+     * Current KaTeX version
+     */
+    version: __VERSION__,
+    /**
+     * Renders the given LaTeX into an HTML+MathML combination, and adds
+     * it as a child to the specified DOM node.
+     */
+    render,
+    /**
+     * Renders the given LaTeX into an HTML+MathML combination string,
+     * for sending to the client.
+     */
+    renderToString,
+    /**
+     * KaTeX error, usually during parsing.
+     */
+    ParseError,
+    /**
+     * The shema of Settings
+     */
+    SETTINGS_SCHEMA,
+    /**
+     * Parses the given LaTeX into KaTeX's internal parse tree structure,
+     * without rendering to HTML or MathML.
+     *
+     * NOTE: This method is not currently recommended for public use.
+     * The internal tree representation is unstable and is very likely
+     * to change. Use at your own risk.
+     */
+    __parse: generateParseTree,
+    /**
+     * Renders the given LaTeX into an HTML+MathML internal DOM tree
+     * representation, without flattening that representation to a string.
+     *
+     * NOTE: This method is not currently recommended for public use.
+     * The internal tree representation is unstable and is very likely
+     * to change. Use at your own risk.
+     */
+    __renderToDomTree: renderToDomTree,
+    /**
+     * Renders the given LaTeX into an HTML internal DOM tree representation,
+     * without MathML and without flattening that representation to a string.
+     *
+     * NOTE: This method is not currently recommended for public use.
+     * The internal tree representation is unstable and is very likely
+     * to change. Use at your own risk.
+     */
+    __renderToHTMLTree: renderToHTMLTree,
+    /**
+     * extends internal font metrics object with a new object
+     * each key in the new object represents a font name
+    */
+    __setFontMetrics: setFontMetrics,
+    /**
+     * adds a new symbol to builtin symbols table
+     */
+    __defineSymbol: defineSymbol,
+    /**
+     * adds a new function to builtin function list,
+     * which directly produce parse tree elements
+     * and have their own html/mathml builders
+     */
+    __defineFunction: defineFunction,
+    /**
+     * adds a new macro to builtin macro list
+     */
+    __defineMacro: defineMacro,
+    /**
+     * Expose the dom tree node types, which can be useful for type checking nodes.
+     *
+     * NOTE: This method is not currently recommended for public use.
+     * The internal tree representation is unstable and is very likely
+     * to change. Use at your own risk.
+     */
+    __domTree: {
+        Span,
+        Anchor,
+        SymbolNode,
+        SvgNode,
+        PathNode,
+        LineNode,
+    },
+};