diff --git a/lib/node/config.js b/lib/node/config.js
index 4d397733..e25a3504 100644
--- a/lib/node/config.js
+++ b/lib/node/config.js
@@ -135,7 +135,8 @@ Config.prototype.set = function set(key, value) {
   if (value == null)
     return;
 
-  key = key.toLowerCase().replace(/-/g, '');
+  key = key.replace(/-/g, '');
+  key = key.toLowerCase();
 
   this.options[key] = value;
 };
@@ -156,7 +157,8 @@ Config.prototype.has = function has(key) {
 
   assert(typeof key === 'string', 'Key must be a string.');
 
-  key = key.toLowerCase().replace(/-/g, '');
+  key = key.replace(/-/g, '');
+  key = key.toLowerCase();
 
   if (this.hash[key] != null)
     return true;
@@ -214,7 +216,8 @@ Config.prototype.get = function get(key, fallback) {
 
   assert(typeof key === 'string', 'Key must be a string.');
 
-  key = key.toLowerCase().replace(/-/g, '');
+  key = key.replace(/-/g, '');
+  key = key.toLowerCase();
 
   if (this.hash[key] != null)
     return this.hash[key];
@@ -735,47 +738,69 @@ Config.prototype.location = function location(file) {
 Config.prototype.parseConfig = function parseConfig(text) {
   assert(typeof text === 'string', 'Config must be text.');
 
-  text = text.trim();
+  if (text.charCodeAt(0) === 0xfeff)
+    text = text.substring(1);
 
-  const parts = text.split(/\n+/);
+  text = text.replace(/\r\n/g, '\n');
+  text = text.replace(/\r/g, '\n');
+  text = text.replace(/\\\n/g, '');
 
-  for (let line of parts) {
-    line = line.trim();
+  let colons = true;
+  let seen = false;
+  let num = 0;
+
+  for (const chunk of text.split('\n')) {
+    const line = chunk.trim();
+
+    num += 1;
 
     if (line.length === 0)
       continue;
 
-    if (/^\s*#/.test(line))
+    if (line[0] === '#')
       continue;
 
-    let eq = line.indexOf('=');
-    const col = line.indexOf(':');
+    const equal = line.indexOf('=');
+    const colon = line.indexOf(':');
 
-    if (col !== -1 && (col < eq || eq === -1))
-      eq = col;
+    let index = -1;
 
-    let key, value;
-    if (eq === -1) {
-      key = line.trim();
-      value = '';
+    if (colon !== -1 && (colon < equal || equal === -1)) {
+      if (seen && !colons)
+        throw new Error(`Expected \`=\` on line ${num}: "${line}".`);
+
+      index = colon;
+      seen = true;
+      colons = true;
+    } else if (equal !== -1) {
+      if (seen && colons)
+        throw new Error(`Expected \`:\` on line ${num}: "${line}".`);
+
+      index = equal;
+      seen = true;
+      colons = false;
     } else {
-      key = line.substring(0, eq).trim();
-      value = line.substring(eq + 1).trim();
+      const symbol = colons ? ':' : '=';
+      throw new Error(`Expected \`${symbol}\` on line ${num}: "${line}".`);
     }
 
-    key = key.replace(/\-/g, '').toLowerCase();
+    let key = line.substring(0, index).trim();
+
+    key = key.replace(/\-/g, '')
+
+    if (!isLowerKey(key))
+      throw new Error(`Invalid option on line ${num}: ${key}.`);
+
+    const value = line.substring(index + 1).trim();
+
+    if (value.length === 0)
+      continue;
 
     const alias = Config.alias[key];
 
     if (alias)
       key = alias;
 
-    if (key.length === 0)
-      continue;
-
-    if (value.length === 0)
-      continue;
-
     this.data[key] = value;
   }
 };
@@ -816,19 +841,21 @@ Config.prototype.parseArg = function parseArg(argv) {
     }
 
     if (arg.indexOf('--') === 0) {
-      // e.g. --opt
-      const parts = arg.split('=');
+      const index = arg.indexOf('=');
 
-      let key = parts[0];
+      let key = null;
       let value = null;
       let empty = false;
 
-      if (parts.length > 1) {
+      if (index !== -1) {
         // e.g. --opt=val
-        value = parts.slice(1).join('=').trim();
+        key = arg.substring(2, index);
+        value = arg.substring(index + 1);
         last = null;
         empty = false;
       } else {
+        // e.g. --opt
+        key = arg.substring(2);
         value = 'true';
         last = null;
         empty = true;
@@ -836,8 +863,8 @@ Config.prototype.parseArg = function parseArg(argv) {
 
       key = key.replace(/\-/g, '');
 
-      if (key.length === 0)
-        continue;
+      if (!isLowerKey(key))
+        throw new Error(`Invalid argument: --${key}.`);
 
       if (value.length === 0)
         continue;
@@ -860,19 +887,32 @@ Config.prototype.parseArg = function parseArg(argv) {
     if (arg[0] === '-') {
       // e.g. -abc
       last = null;
+
       for (let j = 1; j < arg.length; j++) {
         let key = arg[j];
+
+        if ((key < 'a' || key > 'z')
+            && (key < 'A' || key > 'Z')
+            && (key < '0' || key > '9')
+            && key !== '?') {
+          throw new Error(`Invalid argument: -${key}.`);
+        }
+
         const alias = Config.alias[key];
+
         if (alias)
           key = alias;
+
         this.args[key] = 'true';
+
         last = key;
       }
+
       continue;
     }
 
     // e.g. foo
-    const value = arg.trim();
+    const value = arg;
 
     if (value.length === 0) {
       last = null;
@@ -908,24 +948,24 @@ Config.prototype.parseEnv = function parseEnv(env) {
   assert(env && typeof env === 'object');
 
   for (let key of Object.keys(env)) {
-    let value = env[key];
+    const value = env[key];
 
     assert(typeof value === 'string');
 
-    if (key.indexOf(prefix) !== 0)
+    if (!util.startsWith(key, prefix))
       continue;
 
     key = key.substring(prefix.length);
-    key = key.replace(/_/g, '').toLowerCase();
+    key = key.replace(/_/g, '');
 
-    if (key.length === 0)
+    if (!isUpperKey(key))
       continue;
 
-    value = value.trim();
-
     if (value.length === 0)
       continue;
 
+    key = key.toLowerCase();
+
     // Do not allow one-letter aliases.
     if (key.length > 1) {
       const alias = Config.alias[key];
@@ -989,27 +1029,30 @@ Config.prototype.parseForm = function parseForm(query, map) {
   if (query.length === 0)
     return;
 
-  if (query[0] === '?' || query[0] === '#')
+  let ch = '?';
+
+  if (map === this.hash)
+    ch = '#';
+
+  if (query[0] === ch)
     query = query.substring(1);
 
-  const parts = query.split('&');
-
-  for (const pair of parts) {
+  for (const pair of query.split('&')) {
     const index = pair.indexOf('=');
 
     let key, value;
-    if (index === -1) {
-      key = pair;
-      value = '';
-    } else {
+    if (index !== -1) {
       key = pair.substring(0, index);
       value = pair.substring(index + 1);
+    } else {
+      key = pair;
+      value = 'true';
     }
 
     key = unescape(key);
-    key = key.replace(/\-/g, '').toLowerCase();
+    key = key.replace(/\-/g, '');
 
-    if (key.length === 0)
+    if (!isLowerKey(key))
       continue;
 
     value = unescape(value);
@@ -1055,6 +1098,24 @@ function isAlpha(str) {
   return /^[a-z0-9]+$/.test(str);
 }
 
+function isKey(key) {
+  return /^[a-zA-Z0-9]+$/.test(key);
+}
+
+function isLowerKey(key) {
+  if (!isKey(key))
+    return false;
+
+  return !/[A-Z]/.test(key);
+}
+
+function isUpperKey(key) {
+  if (!isKey(key))
+    return false;
+
+  return !/[a-z]/.test(key);
+}
+
 /*
  * Expose
  */