diff --git a/api_test/main.c b/api_test/main.c
index 1a41e694a..790327c62 100644
--- a/api_test/main.c
+++ b/api_test/main.c
@@ -942,6 +942,13 @@ static void test_feed_across_line_ending(test_batch_runner *runner) {
 #  include <sys/time.h>
 static struct timeval _before, _after;
 static int _timing;
+static int _timing_scale = 1;
+#  define SETUP_TIMING()                        \
+  do {                                          \
+    char *scale = getenv("CMARK_TIMING_SCALE"); \
+    if (scale)                                  \
+      _timing_scale = atoi(scale);              \
+  } while (0)
 #  define START_TIMING() \
        gettimeofday(&_before, NULL)
 
@@ -952,10 +959,13 @@ static int _timing;
         } while (0)
 
 #  define TIMING _timing
+#  define TIMING_SCALE _timing_scale
 #else
+#  define SETUP_TIMING()
 #  define START_TIMING()
 #  define END_TIMING()
 #  define TIMING 0
+#  define TIMING_SCALE 1
 #endif
 
 static void test_pathological_regressions(test_batch_runner *runner) {
@@ -973,7 +983,8 @@ static void test_pathological_regressions(test_batch_runner *runner) {
     free(html);
     free(input);
 
-    OK(runner, TIMING < 1000, "takes less than 1000ms to run");
+    OK(runner, TIMING < 1000 * TIMING_SCALE,
+       "takes less than CMARK_TIMING_SCALE * 1000ms to run");
   }
 
   {
@@ -989,7 +1000,8 @@ static void test_pathological_regressions(test_batch_runner *runner) {
     free(html);
     free(input);
 
-    OK(runner, TIMING < 1000, "takes less than 1000ms to run");
+    OK(runner, TIMING < 1000 * TIMING_SCALE,
+       "takes less than CMARK_TIMING_SCALE * 1000ms to run");
   }
 }
 
@@ -1133,6 +1145,7 @@ int main() {
   int retval;
   test_batch_runner *runner = test_batch_runner_new();
 
+  SETUP_TIMING();
   cmark_enable_safety_checks(true);
   version(runner);
   constructor(runner);
diff --git a/man/man1/cmark-gfm.1 b/man/man1/cmark-gfm.1
index 4fca62732..c25791c33 100644
--- a/man/man1/cmark-gfm.1
+++ b/man/man1/cmark-gfm.1
@@ -66,6 +66,18 @@ URLs are those that begin with `javascript:`, `vbscript:`,
 `file:`, or `data:` (except for `image/png`, `image/gif`,
 `image/jpeg`, or `image/webp` mime types).
 .TP 12n
+.B \-\-github-pre-lang
+Use GitHub-style <pre lang> for code blocks.
+.TP 12n
+.B \-\-strikethrough-double-tilde
+Only parse strikethrough (if enabled) with two tildes.
+.TP 12n
+.B \-\-table-prefer-style-attributes
+Use style attributes to align table cells instead of align attributes.
+.TP 12n
+.B \-\-full-info-string
+Include remainder of code block info string in a separate attribute.
+.TP 12n
 .B \-\-help
 Print usage information.
 .TP 12n
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 84dd2a037..6a67078f1 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -175,6 +175,10 @@ if(CMARK_SHARED OR CMARK_STATIC)
     DESTINATION include
     )
 
+  install(FILES ${HEADERS}
+    DESTINATION include/cmark-gfm
+    )
+
   install(EXPORT cmark-gfm DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake)
 endif()
 
diff --git a/test/normalize.py b/test/normalize.py
index b7fd9b245..ec4979c0b 100644
--- a/test/normalize.py
+++ b/test/normalize.py
@@ -18,7 +18,7 @@ class HTMLParseError(Exception):
 # Normalization code, adapted from
 # https://github.com/karlcow/markdown-testsuite/
 significant_attrs = ["alt", "href", "src", "title"]
-whitespace_re = re.compile('\s+')
+whitespace_re = re.compile('\\s+')
 class MyHTMLParser(HTMLParser):
     def __init__(self):
         HTMLParser.__init__(self)
@@ -176,7 +176,7 @@ def normalize_html(html):
         '\u2200&amp;&gt;&lt;&quot;'
 
     """
-    html_chunk_re = re.compile("(\<!\[CDATA\[.*?\]\]\>|\<[^>]*\>|[^<]+)")
+    html_chunk_re = re.compile("(\\<!\\[CDATA\\[.*?\\]\\]\\>|\\<[^>]*\\>|[^<]+)")
     try:
         parser = MyHTMLParser()
         # We work around HTMLParser's limitations parsing CDATA
diff --git a/test/pathological_tests.py b/test/pathological_tests.py
index d0e910c5e..c2fdff64d 100644
--- a/test/pathological_tests.py
+++ b/test/pathological_tests.py
@@ -7,6 +7,7 @@
 import platform
 import itertools
 import multiprocessing
+import os
 from cmark import CMark
 
 def hash_collisions():
@@ -29,7 +30,7 @@ def badhash(ref):
 
     document = ''.join("[%s]: /url\n\n[%s]\n\n" % (key, bad_key) for key in collisions)
 
-    return document, re.compile("(<p>\[%s\]</p>\n){%d}" % (bad_key, COUNT-1))
+    return document, re.compile("(<p>\\[%s\\]</p>\n){%d}" % (bad_key, COUNT-1))
 
 allowed_failures = {"many references": True}
 
@@ -47,10 +48,10 @@ def badhash(ref):
                   re.compile("(_a ){64999}_a")),
     "many link closers with no openers":
                  (("a]" * 65000),
-                  re.compile("(a\]){65000}")),
+                  re.compile("(a\\]){65000}")),
     "many link openers with no closers":
                  (("[a" * 65000),
-                  re.compile("(\[a){65000}")),
+                  re.compile("(\\[a){65000}")),
     "mismatched openers and closers":
                  (("*a_ " * 50000),
                   re.compile("([*]a[_] ){49999}[*]a_")),
@@ -59,19 +60,19 @@ def badhash(ref):
                   re.compile("a[*][*]b(c[*] ){49999}c[*]")),
     "link openers and emph closers":
                  (("[ a_" * 50000),
-                  re.compile("(\[ a_){50000}")),
+                  re.compile("(\\[ a_){50000}")),
     "pattern [ (]( repeated":
                  (("[ (](" * 80000),
-                  re.compile("(\[ \(\]\(){80000}")),
+                  re.compile("(\\[ \\(\\]\\(){80000}")),
     "pattern ![[]() repeated":
                  ("![[]()" * 160000,
-                  re.compile("(!\[<a href=\"\"></a>){160000}")),
+                  re.compile("(!\\[<a href=\"\"></a>){160000}")),
     "hard link/emph case":
                  ("**x [a*b**c*](d)",
                   re.compile("\\*\\*x <a href=\"d\">a<em>b\\*\\*c</em></a>")),
     "nested brackets":
                  (("[" * 50000) + "a" + ("]" * 50000),
-                  re.compile("\[{50000}a\]{50000}")),
+                  re.compile("\\[{50000}a\\]{50000}")),
     "nested block quotes":
                  ((("> " * 50000) + "a"),
                   re.compile("(<blockquote>\n){50000}")),
@@ -86,13 +87,13 @@ def badhash(ref):
                   re.compile("^<p>[e`]*</p>\n$")),
     "unclosed links A":
                  ("[a](<b" * 30000,
-                  re.compile("(\[a\]\(&lt;b){30000}")),
+                  re.compile("(\\[a\\]\\(&lt;b){30000}")),
     "unclosed links B":
                  ("[a](b" * 30000,
-                  re.compile("(\[a\]\(b){30000}")),
+                  re.compile("(\\[a\\]\\(b){30000}")),
     "unclosed <!--":
                  ("</" + "<!--" * 300000,
-                  re.compile("\&lt;\/(\&lt;!--){300000}")),
+                  re.compile("\\&lt;\\/(\\&lt;!--){300000}")),
     "tables":
                  ("aaa\rbbb\n-\v\n" * 30000,
                   re.compile("^<p>aaa</p>\n<table>\n<thead>\n<tr>\n<th>bbb</th>\n</tr>\n</thead>\n<tbody>\n(<tr>\n<td>aaa</td>\n</tr>\n<tr>\n<td>bbb</td>\n</tr>\n<tr>\n<td>-\x0b</td>\n</tr>\n){29999}</tbody>\n</table>\n$")),
@@ -106,7 +107,8 @@ def badhash(ref):
 passed = 0
 errored = 0
 ignored = 0
-TIMEOUT = 5
+timing_scale = float(os.getenv("CMARK_TIMING_SCALE", "1"))
+TIMEOUT = 5 * timing_scale
 
 def run_test(inp, regex):
     parser = argparse.ArgumentParser(description='Run cmark tests.')
@@ -144,12 +146,12 @@ def run_test(inp, regex):
             p.terminate()
             p.join()
             print('[TIMED OUT]')
-            if allowed_failures[description]:
+            if description in allowed_failures:
                 ignored += 1
             else:
                 errored += 1
         elif p.exitcode != 0:
-            if allowed_failures[description]:
+            if description in allowed_failures:
                 ignored += 1
             else:
                 errored += 1