diff --git a/pynini.egg-info/PKG-INFO b/pynini.egg-info/PKG-INFO
index 314faa0..40e09f1 100644
--- a/pynini.egg-info/PKG-INFO
+++ b/pynini.egg-info/PKG-INFO
@@ -6,6 +6,7 @@ Home-page: http://pynini.opengrm.org/
 Author: Kyle Gorman
 Author-email: kbg@google.com
 License: UNKNOWN
+Description-Content-Type: UNKNOWN
 Description: UNKNOWN
 Keywords: natural language processing,speech recognition,machine learning
 Platform: UNKNOWN
diff --git a/pynini.egg-info/SOURCES.txt b/pynini.egg-info/SOURCES.txt
index 37f146e..f2f6727 100644
--- a/pynini.egg-info/SOURCES.txt
+++ b/pynini.egg-info/SOURCES.txt
@@ -7,6 +7,7 @@ NEWS
 README.rst
 pynini.pdf
 pynini_test.py
+setup.cfg
 setup.py
 pynini.egg-info/PKG-INFO
 pynini.egg-info/SOURCES.txt
diff --git a/setup.py b/setup.py
index 056816d..de38cb9 100644
--- a/setup.py
+++ b/setup.py
@@ -19,20 +19,46 @@
 from setuptools import Extension
 from setuptools import setup
 
+import os
+import platform
+
+PROJ_DIR = os.path.dirname(os.path.realpath(__file__))
+
+if platform.system() == 'Linux':
+    OS='linux'
+elif platform.system() == 'Darwin':
+    OS='osx'
+    from distutils import sysconfig
+    config_vars = sysconfig.get_config_vars()
+    config_vars['LDSHARED'] = config_vars['LDSHARED'].replace('-bundle', '-dynamiclib')
 
 COMPILE_ARGS = ["-std=c++11",
                 "-Wno-unused-function",
                 "-Wno-unused-local-typedef",
                 "-funsigned-char"]
 
+INCLUDE_DIRS = [os.path.join(PROJ_DIR, p).format(OS) for p in [
+    "mason_packages/{}-x86_64/openfst/1.6.7/include",
+    "mason_packages/{}-x86_64/re2/2017-08-01/include",
+]]
+
+LIBRARY_DIRS = [os.path.join(PROJ_DIR, p).format(OS) for p in [
+    "mason_packages/{}-x86_64/openfst/1.6.7/lib",
+    "mason_packages/{}-x86_64/re2/2017-08-01/lib",
+]]
+
 pywrapfst = Extension(name="pywrapfst", language="c++",
                       extra_compile_args=COMPILE_ARGS,
+                      library_dirs=LIBRARY_DIRS,
+                      include_dirs=INCLUDE_DIRS,
                       libraries=["fstfarscript", "fstfar", "fstscript",
                                  "fst", "m", "dl"],
                       sources=["src/pywrapfst.cc"])
 
 pynini = Extension(name="pynini", language="c++",
                    extra_compile_args=COMPILE_ARGS,
+                   library_dirs=LIBRARY_DIRS,
+                   include_dirs=INCLUDE_DIRS,
                    libraries=["re2",
                               "fstfarscript",
                               "fstpdtscript",