diff --git a/lib/postprocessing.py b/lib/postprocessing.py
new file mode 100644
index 0000000..d0b85e6
--- /dev/null
+++ b/lib/postprocessing.py
@@ -0,0 +1,87 @@
+import re
+import fmt.comments
+
+def postprocess(answer, keyword, options, request_options=None):
+    answer = _answer_add_comments(answer, request_options=request_options)
+    answer = _answer_filter_by_keyword(answer, keyword, options, request_options=request_options)
+    return answer
+
+def _answer_add_comments(answer, request_options=None):
+
+    if answer['format'] != 'text+code':
+        return answer
+
+    topic = answer['topic']
+    filetype = 'bash'
+    if '/' in topic:
+        filetype = topic.split('/', 1)[0]
+        if filetype.startswith('q:'):
+            filetype = filetype[2:]
+
+    answer['answer'] = fmt.comments.beautify(
+        answer['answer'].encode('utf-8'), filetype, request_options)
+    answer['format'] = 'code'
+    return answer
+
+def _answer_filter_by_keyword(answer, keyword, options, request_options=None):
+    answer['answer'] = _filter_by_keyword(answer['answer'], keyword, options)
+    return answer
+
+def _filter_by_keyword(answer, keyword, options):
+
+    def _join_paragraphs(paragraphs):
+        answer = "\n".join(paragraphs)
+        return answer
+
+    def _split_paragraphs(text):
+        answer = []
+        paragraph = ""
+        for line in text.splitlines():
+            if line == "":
+                answer.append(paragraph)
+                paragraph = ""
+            else:
+                paragraph += line+"\n"
+        answer.append(paragraph)
+        return answer
+
+    def _paragraph_contains(paragraph, keyword, insensitive=False, word_boundaries=True):
+        """
+        Check if `paragraph` contains `keyword`.
+        Several keywords can be joined together using ~
+        For example: ~ssh~passphrase
+        """
+        answer = True
+
+        if '~' in keyword:
+            keywords = keyword.split('~')
+        else:
+            keywords = [keyword]
+
+        for kwrd in keywords:
+            regex = re.escape(kwrd)
+            if not word_boundaries:
+                regex = r"\b%s\b" % kwrd
+
+            if insensitive:
+                answer = answer and bool(re.search(regex, paragraph, re.IGNORECASE))
+            else:
+                answer = answer and bool(re.search(regex, paragraph))
+
+        return answer
+
+
+    if not keyword:
+        return answer
+
+    search_options = {
+        'insensitive': 'i' in options,
+        'word_boundaries': 'b' in options
+    }
+
+    paragraphs = [p for p in _split_paragraphs(answer)
+                  if _paragraph_contains(p, keyword, **search_options)]
+    if not paragraphs:
+        return ""
+
+    return _join_paragraphs(paragraphs)