diff --git a/lib/lexer_block/fences.js b/lib/lexer_block/fences.js
index 8bd246a..4cba9ab 100644
--- a/lib/lexer_block/fences.js
+++ b/lib/lexer_block/fences.js
@@ -3,11 +3,13 @@
 'use strict';
 
 
-var skipEmptyLines = require('../helpers').skipEmptyLines;
+var skipEmptyLines  = require('../helpers').skipEmptyLines;
+var skipSpaces      = require('../helpers').skipSpaces;
+var skipChars       = require('../helpers').skipChars;
 
 
 module.exports =function fences(state, startLine, endLine, silent) {
-  var marker, len, params, nextLine,
+  var marker, len, params, nextLine, mem,
       pos = state.bMarks[startLine] + state.tShift[startLine],
       max = state.eMarks[startLine];
 
@@ -20,43 +22,41 @@ module.exports =function fences(state, startLine, endLine, silent) {
   }
 
   // scan marker length
-  len = 1;
-  while (state.src.charCodeAt(++pos) === marker) {
-    len++;
-  }
+  mem = pos;
+  pos = skipChars(state, pos, marker);
+
+  len = pos - mem;
 
   if (len < 3) { return false; }
 
   params = state.src.slice(pos, max).trim();
 
-  if (!/\S/.test(params)) { return false; }
-
   // search end of block
   nextLine = startLine;
 
   do {
     nextLine++;
 
-    if (nextLine > endLine) { return false; }
+    if (nextLine >= endLine) {
+      // unclosed block should be autoclosed by end of document.
+      if (state.blkLevel === 0) {
+        break;
+      }
+      return false;
+    }
 
-    pos = state.bMarks[nextLine] + state.tShift[nextLine];
+    pos = mem = state.bMarks[nextLine] + state.tShift[nextLine];
     max = state.eMarks[nextLine];
 
-    if (pos + 3 > max) { continue; }
+    if (state.src.charCodeAt(pos) !== marker) { continue; }
 
-    // check markers
-    if (state.src.charCodeAt(pos) !== marker &&
-        state.src.charCodeAt(pos + 1) !== marker &&
-        state.src.charCodeAt(pos + 2) !== marker) {
-      continue;
-    }
+    pos = skipChars(state, pos, marker);
 
-    pos += 3;
+    // closing code fence must be at least as long as the opening one
+    if (pos - mem < len) { continue; }
 
     // make sure tail has spaces only
-    //pos = pos < max ? skipSpaces(state, pos) : pos;
-
-    // stmd allow any combonation of markers and spaces in tail
+    pos = skipSpaces(state, pos);
 
     if (pos < max) { continue; }
 
@@ -69,7 +69,7 @@ module.exports =function fences(state, startLine, endLine, silent) {
 
   state.tokens.push({
     type: 'fence',
-    params: params.split(/\s+/g),
+    params: params ? params.split(/\s+/g) : [],
     startLine: startLine + 1,
     endLine: nextLine
   });
diff --git a/lib/renderer.js b/lib/renderer.js
index 4cf477f..a1ab94d 100644
--- a/lib/renderer.js
+++ b/lib/renderer.js
@@ -1,13 +1,16 @@
 'use strict';
 
 
-function escapeHTML(str) {
-  return str.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
+function escapeHtml(str) {
+  return str.replace(/&/g, '&amp;')
+            .replace(/</g, '&lt;')
+            .replace(/>/g, '&gt;')
+            .replace(/"/g, '&quot;');
 }
 
 var MD_UNESCAPE_RE = /\\([!"#$%&\'()*+,.\/:;<=>?@[\\\]^_`{|}~-])/g;
 
-function unescapeMD(str) {
+function unescapeMd(str) {
   return str.replace(MD_UNESCAPE_RE, '$1');
 }
 
@@ -40,19 +43,20 @@ rules.bullet_list_close = function (state, token) {
 rules.code = function (state, token) {
   var content = joinLines(state, token.startLine, token.endLine).replace(/^ {4}/gm, '');
 
-  state.result += '<pre><code>' + escapeHTML(content) + '</code></pre>\n';
+  state.result += '<pre><code>' + escapeHtml(content) + '</code></pre>\n';
 };
 
 
 rules.fence = function (state, token) {
   var content = joinLines(state, token.startLine, token.endLine);
   var langMark = '';
+  var langPrefix = state.options.codeLangPrefix || '';
 
   if (token.params.length) {
-    langMark = ' class="language-' + escapeHTML(token.params[0]) + '"';
+    langMark = ' class="' + langPrefix + escapeHtml(token.params[0]) + '"';
   }
 
-  state.result += '<pre><code' + langMark + '>' + escapeHTML(content) + '</code></pre>\n';
+  state.result += '<pre><code' + langMark + '>' + escapeHtml(content) + '</code></pre>\n';
 };
 
 
@@ -86,7 +90,7 @@ rules.paragraph_close = function (state, token) {
 
 
 rules.text = function (state, token) {
-  state.result += escapeHTML(unescapeMD(state.src.slice(token.begin, token.end)));
+  state.result += escapeHtml(unescapeMd(state.src.slice(token.begin, token.end)));
 };
 
 
diff --git a/test/fixtures/remarkable/code/fence_matching.html b/test/fixtures/remarkable/code/fence_matching.html
new file mode 100644
index 0000000..5c8833a
--- /dev/null
+++ b/test/fixtures/remarkable/code/fence_matching.html
@@ -0,0 +1,8 @@
+<pre><code class="abc">```
+</code></pre>
+<pre><code class="blah">
+`````
+
+````
+
+</code></pre>
diff --git a/test/fixtures/stmd_pending/Code/FenceMatching.markdown b/test/fixtures/remarkable/code/fence_matching.md
similarity index 100%
rename from test/fixtures/stmd_pending/Code/FenceMatching.markdown
rename to test/fixtures/remarkable/code/fence_matching.md
diff --git a/test/fixtures/remarkable/code/fenced_code_blocks.html b/test/fixtures/remarkable/code/fenced_code_blocks.html
new file mode 100644
index 0000000..5452844
--- /dev/null
+++ b/test/fixtures/remarkable/code/fenced_code_blocks.html
@@ -0,0 +1,24 @@
+<p>This is a fenced code block:</p>
+<pre><code class="haskell">pairs :: [(Int,Char)]
+pairs = [(x,y) | x &lt;- [0..10], y &lt;- ['a'..'z']]
+</code></pre>
+<p>Here is one with tildes:</p>
+<pre><code class="haskell">pairs :: [(Int,Char)]
+pairs = [(x,y) | x &lt;- [0..10], y &lt;- ['a'..'z']]
+</code></pre>
+<p>More metadata:</p>
+<pre><code class="haskell">pairs :: [(Int,Char)]
+pairs = [(x,y) | x &lt;- [0..10], y &lt;- ['a'..'z']]
+</code></pre>
+<p>More backticks:</p>
+<pre><code class="haskell">pairs :: [(Int,Char)]
+pairs = [(x,y) | x &lt;- [0..10], y &lt;- ['a'..'z']]
+
+backticks :: String
+backticks = &quot;`````&quot;
+</code></pre>
+<p>Without an end:</p>
+<pre><code>code with
+no end
+
+</code></pre>
diff --git a/test/fixtures/stmd_pending/Code/FencedCodeBlocks.markdown b/test/fixtures/remarkable/code/fenced_code_blocks.md
similarity index 100%
rename from test/fixtures/stmd_pending/Code/FencedCodeBlocks.markdown
rename to test/fixtures/remarkable/code/fenced_code_blocks.md
diff --git a/test/fixtures/remarked_pending/gfm_code.html b/test/fixtures/remarked_conflicting/code/gfm_code.html
similarity index 100%
rename from test/fixtures/remarked_pending/gfm_code.html
rename to test/fixtures/remarked_conflicting/code/gfm_code.html
diff --git a/test/fixtures/remarked_pending/gfm_code.md b/test/fixtures/remarked_conflicting/code/gfm_code.md
similarity index 100%
rename from test/fixtures/remarked_pending/gfm_code.md
rename to test/fixtures/remarked_conflicting/code/gfm_code.md
diff --git a/test/fixtures/stmd_pending/Code/FenceMatching.html b/test/fixtures/stmd_conflicting/Code/FenceMatching.html
similarity index 100%
rename from test/fixtures/stmd_pending/Code/FenceMatching.html
rename to test/fixtures/stmd_conflicting/Code/FenceMatching.html
diff --git a/test/fixtures/stmd_conflicting/Code/FenceMatching.markdown b/test/fixtures/stmd_conflicting/Code/FenceMatching.markdown
new file mode 100644
index 0000000..d86169a
--- /dev/null
+++ b/test/fixtures/stmd_conflicting/Code/FenceMatching.markdown
@@ -0,0 +1,10 @@
+````abc
+```
+````
+``````blah
+
+`````
+
+````
+
+```````````
diff --git a/test/fixtures/stmd_pending/Code/FencedCodeBlocks.html b/test/fixtures/stmd_conflicting/Code/FencedCodeBlocks.html
similarity index 100%
rename from test/fixtures/stmd_pending/Code/FencedCodeBlocks.html
rename to test/fixtures/stmd_conflicting/Code/FencedCodeBlocks.html
diff --git a/test/fixtures/stmd_conflicting/Code/FencedCodeBlocks.markdown b/test/fixtures/stmd_conflicting/Code/FencedCodeBlocks.markdown
new file mode 100644
index 0000000..6ccc6be
--- /dev/null
+++ b/test/fixtures/stmd_conflicting/Code/FencedCodeBlocks.markdown
@@ -0,0 +1,35 @@
+This is a fenced code block:
+```haskell
+pairs :: [(Int,Char)]
+pairs = [(x,y) | x <- [0..10], y <- ['a'..'z']]
+```
+Here is one with tildes:
+
+~~~ haskell
+pairs :: [(Int,Char)]
+pairs = [(x,y) | x <- [0..10], y <- ['a'..'z']]
+~~~
+
+More metadata:
+
+```haskell numberLines start=50
+pairs :: [(Int,Char)]
+pairs = [(x,y) | x <- [0..10], y <- ['a'..'z']]
+```
+
+More backticks:
+
+```````` haskell
+pairs :: [(Int,Char)]
+pairs = [(x,y) | x <- [0..10], y <- ['a'..'z']]
+
+backticks :: String
+backticks = "`````"
+`````````````
+
+Without an end:
+
+```
+code with
+no end
+
diff --git a/test/remarked.js b/test/remarked.js
index 3a5634c..9a21f30 100644
--- a/test/remarked.js
+++ b/test/remarked.js
@@ -12,6 +12,11 @@ var Remarked = require('../');
 describe('remarked', function () {
   var md = new Remarked();
 
+  // Set options, to give output more close to remarked
+  md.set({
+    codeLangPrefix: 'lang-'
+  });
+
   utils.addTests(path.join(__dirname, 'fixtures/remarked_ok'), md);
 });
 
diff --git a/test/utils.js b/test/utils.js
index 8ece3cb..b32a63a 100644
--- a/test/utils.js
+++ b/test/utils.js
@@ -41,11 +41,11 @@ function addTests(dir, md, skip) {
 
       if (!skip) {
         it(base, function () {
-          assert.strictEqual(right, md.render(src));
+          assert.strictEqual(md.render(src), right);
         });
       } else {
         it.skip(base, function () {
-          assert.strictEqual(right, md.render(src));
+          assert.strictEqual(md.render(src), right);
         });
       }
     }