diff --git a/static/js/components/literate-programming.js b/static/js/components/literate-programming.js
index 28ab03f..fc5e7b6 100644
--- a/static/js/components/literate-programming.js
+++ b/static/js/components/literate-programming.js
@@ -35,77 +35,10 @@ function getLiterateProgramWorkerCommands(name, count) {
     return commands;
 }
 
+const javascriptJson = await (await fetch(`${TREEHOUSE_SITE}/static/syntax/javascript.json`)).text();
+
 class InputMode {
-    static JAVASCRIPT = compileSyntax({
-        patterns: [
-            { regex: /\/\/.*/, as: "comment" },
-            { regex: /\/\*.*?\*\//ms, as: "comment" },
-            { regex: /[A-Z_][a-zA-Z0-9_]*/, as: "keyword2" },
-            { regex: /[a-zA-Z_][a-zA-Z0-9_]*(?=\()/, as: "function" },
-            { regex: /[a-zA-Z_][a-zA-Z0-9_]*/, as: "identifier" },
-            { regex: /0[bB][01_]+n?/, as: "literal" },
-            { regex: /0[oO][0-7_]+n?/, as: "literal" },
-            { regex: /0[xX][0-9a-fA-F_]+n?/, as: "literal" },
-            { regex: /[0-9_]+n/, as: "literal" },
-            { regex: /[0-9_]+(\.[0-9_]*([eE][-+]?[0-9_]+)?)?/, as: "literal" },
-            { regex: /'(\\'|[^'])*'/, as: "string" },
-            { regex: /"(\\"|[^"])*"/, as: "string" },
-            { regex: /`(\\`|[^"])*`/, as: "string" },
-            // TODO: RegExp literals?
-            { regex: /[+=/*^%<>!~|&\.?:-]+/, as: "operator" },
-            { regex: /[,;]/, as: "punct" },
-        ],
-        keywords: new Map([
-            ["as", { into: "keyword1", onlyReplaces: "identifier" }],
-            ["async", { into: "keyword1", onlyReplaces: "identifier" }],
-            ["await", { into: "keyword1" }],
-            ["break", { into: "keyword1" }],
-            ["case", { into: "keyword1" }],
-            ["catch", { into: "keyword1" }],
-            ["class", { into: "keyword1" }],
-            ["const", { into: "keyword1" }],
-            ["continue", { into: "keyword1" }],
-            ["debugger", { into: "keyword1" }],
-            ["default", { into: "keyword1" }],
-            ["delete", { into: "keyword1" }],
-            ["do", { into: "keyword1" }],
-            ["else", { into: "keyword1" }],
-            ["export", { into: "keyword1" }],
-            ["extends", { into: "keyword1" }],
-            ["finally", { into: "keyword1" }],
-            ["for", { into: "keyword1" }],
-            ["from", { into: "keyword1", onlyReplaces: "identifier" }],
-            ["function", { into: "keyword1" }],
-            ["get", { into: "keyword1", onlyReplaces: "identifier" }],
-            ["if", { into: "keyword1" }],
-            ["import", { into: "keyword1" }],
-            ["in", { into: "keyword1" }],
-            ["instanceof", { into: "keyword1" }],
-            ["let", { into: "keyword1" }],
-            ["new", { into: "keyword1" }],
-            ["of", { into: "keyword1", onlyReplaces: "identifier" }],
-            ["return", { into: "keyword1" }],
-            ["set", { into: "keyword1", onlyReplaces: "identifier" }],
-            ["static", { into: "keyword1" }],
-            ["switch", { into: "keyword1" }],
-            ["throw", { into: "keyword1" }],
-            ["try", { into: "keyword1" }],
-            ["typeof", { into: "keyword1" }],
-            ["var", { into: "keyword1" }],
-            ["void", { into: "keyword1" }],
-            ["while", { into: "keyword1" }],
-            ["with", { into: "keyword1" }],
-            ["yield", { into: "keyword1" }],
-
-            ["super", { into: "keyword2" }],
-            ["this", { into: "keyword2" }],
-
-            ["false", { into: "literal" }],
-            ["true", { into: "literal" }],
-            ["undefined", { into: "literal" }],
-            ["null", { into: "literal" }],
-        ]),
-    })
+    static JAVASCRIPT = compileSyntax(JSON.parse(javascriptJson));
 
     constructor(frame) {
         this.frame = frame;
diff --git a/static/js/components/literate-programming/highlight.js b/static/js/components/literate-programming/highlight.js
index 59af6a1..a09b3b4 100644
--- a/static/js/components/literate-programming/highlight.js
+++ b/static/js/components/literate-programming/highlight.js
@@ -6,12 +6,15 @@
 
 export function compileSyntax(def) {
     for (let pattern of def.patterns) {
-        // Remove g (global) flag as it would interfere with the lexis process. We only want to match
-        // the first token at the cursor.
-        let flags = pattern.regex.flags.replace("g", "");
-        // Add d (indices) and y (sticky) flags so that we can tell where the matches start and end.
-        pattern.regex = new RegExp(pattern.regex, "y" + flags);
+        let flags = "dy";
+        if (pattern.flags != null) {
+            if ("dotMatchesNewline" in pattern.flags) {
+                flags += "s";
+            }
+        }
+        pattern.regex = new RegExp(pattern.regex, flags);
     }
+    def.keywords = new Map(Object.entries(def.keywords));
     return def;
 }
 
@@ -34,7 +37,18 @@ function tokenize(text, syntax) {
             let match;
             pattern.regex.lastIndex = i;
             if ((match = pattern.regex.exec(text)) != null) {
-                pushToken(tokens, pattern.is, match[0]); // TODO
+                if (typeof pattern.is == "object") {
+                    let lastMatchEnd = i;
+                    for (let i = 1; i < match.indices.length; ++i) {
+                        let [start, end] = match.indices[i];
+                        if (match.indices[i] != null) {
+                            pushToken(tokens, pattern.is.default, text.substring(lastMatchEnd, start));
+                            pushToken(tokens, pattern.is.captures[i], text.substring(start, end));
+                        }
+                    }
+                } else {
+                    pushToken(tokens, pattern.is, match[0]);
+                }
                 i = pattern.regex.lastIndex;
                 hadMatch = true;
                 break;
diff --git a/static/syntax/javascript.json b/static/syntax/javascript.json
index 06dcde9..db48e73 100644
--- a/static/syntax/javascript.json
+++ b/static/syntax/javascript.json
@@ -17,9 +17,9 @@
         { "regex": "0[xX][0-9a-fA-F_]+n?", "is": "literal" },
         { "regex": "[0-9_]+n", "is": "literal" },
         { "regex": "[0-9_]+(\\.[0-9_]*([eE][-+]?[0-9_]+)?)?", "is": "literal" },
-        { "regex": "'(\\'|[^'])*'", "is": "string" },
-        { "regex": "\"(\\\"|[^\"])*\"", "is": "string" },
-        { "regex": "`(\\`|[^`])*`", "is": "string" },
+        { "regex": "'(\\\\'|[^'])*'", "is": "string" },
+        { "regex": "\"(\\\\\"|[^\"])*\"", "is": "string" },
+        { "regex": "`(\\\\`|[^`])*`", "is": "string" },
         { "regex": "[+=/*^%<>!~|&\\.?:-]+", "is": "operator" },
         { "regex": "[,;]", "is": "punct" }
     ],