diff --git a/.travis.yml b/.travis.yml
index 691fa5f30..318cfff21 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -44,11 +44,31 @@ matrix:
         - PYTHON_BUILD=true
         - BREW_BUNDLE=true
 
-    - name: "klayout python3.6.5_1 osx10.13"
+    - name: "klayout python3.6.6 osx10.13"
       os: osx
       osx_image: xcode9.4  # macOS 10.13
       env:
-        - MATRIX_EVAL="brew update; brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/f2a764ef944b1080be64bd88dca9a1d80130c558/Formula/python.rb; brew switch python 3.6.5_1; shopt -s expand_aliases; alias python='python3'; alias pip='pip3';"
+        - MATRIX_EVAL="brew update; brew install sashkab/python/python36; brew link --force --overwrite python36; shopt -s expand_aliases; alias python='/usr/local/opt/python36/bin/python3.6'; alias pip='/usr/local/opt/python36/bin/pip3.6';"
+        - ARCHFLAGS="-std=c++11"
+        - PIP_UPDATE="1"
+        - PYTHON_BUILD=true
+        - BREW_BUNDLE=false
+
+    - name: "klayout python3.5.6 osx10.13"
+      os: osx
+      osx_image: xcode9.4  # macOS 10.13
+      env:
+        - MATRIX_EVAL="brew update; brew install sashkab/python/python35; brew link --force --overwrite python35; shopt -s expand_aliases; alias python='/usr/local/opt/python35/bin/python3.5'; alias pip='/usr/local/opt/python35/bin/pip3.5';"
+        - ARCHFLAGS="-std=c++11"
+        - PIP_UPDATE="1"
+        - PYTHON_BUILD=true
+        - BREW_BUNDLE=false
+
+    - name: "klayout python3.4.9 osx10.13"
+      os: osx
+      osx_image: xcode9.4  # macOS 10.13
+      env:
+        - MATRIX_EVAL="brew update; brew install sashkab/python/python34; brew link --force --overwrite python34; shopt -s expand_aliases; alias python='/usr/local/opt/python34/bin/python3.4'; alias pip='/usr/local/opt/python34/bin/pip3.4';"
         - ARCHFLAGS="-std=c++11"
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
@@ -68,12 +88,26 @@ matrix:
       os: osx
       osx_image: xcode8  # macOS 10.11
       env:
-        - MATRIX_EVAL="brew update; brew config; brew upgrade python;"
+        - MATRIX_EVAL="brew update; brew config; brew upgrade python; brew postinstall python; ls -l /usr/local/opt/python/libexec/bin/; shopt -s expand_aliases; alias python='/usr/local/opt/python/libexec/bin/python'; alias pip='/usr/local/opt/python/libexec/bin/pip';"
         - ARCHFLAGS="-std=c++11"
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
     
+    - name: "klayout python3.7 package"
+      os: linux
+      dist: trusty # Ubuntu 14.04
+      sudo: false
+      language: python
+      python: '3.7-dev'
+      env:
+        - MATRIX_EVAL=""
+        - PIP_UPDATE="1"
+        - PYTHON_BUILD=true
+        - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
+
     - name: "klayout python3.6 package"
       os: linux
       dist: trusty # Ubuntu 14.04
@@ -85,6 +119,8 @@ matrix:
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
     
     - name: "klayout python2.7 package"
       os: linux
@@ -97,6 +133,8 @@ matrix:
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
     
     - name: "klayout python2.6 package"
       os: linux
@@ -109,6 +147,8 @@ matrix:
         - PIP_UPDATE="0"  # setuptools installed from last pip has syntax error on py 2.6
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
     
     - name: "klayout python3.3 package"
       os: linux
@@ -121,6 +161,8 @@ matrix:
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
     
     - name: "klayout python3.4 package"
       os: linux
@@ -133,6 +175,8 @@ matrix:
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
     
     - name: "klayout python3.5 package"
       os: linux
@@ -145,6 +189,8 @@ matrix:
         - PIP_UPDATE="1"
         - PYTHON_BUILD=true
         - BREW_BUNDLE=false
+        - CC=clang
+        - CXX=clang++
 
     # KLayout builds for mac
     # Python 3
@@ -211,7 +257,6 @@ matrix:
 
 before_install:
   - env
-  - rvm install ruby --latest
   - gem install dropbox-deployment
   - eval "${MATRIX_EVAL}"
   - if [ "$BREW_BUNDLE" = true ]; then
@@ -232,6 +277,7 @@ script:
         python setup.py build;
         python setup.py bdist_wheel;
         python setup.py install;
+        python -m unittest testdata/pymod/import_db.py  testdata/pymod/import_rdb.py testdata/pymod/import_tl.py;
         mkdir -p deploy/dist-pymod;
         cp -a dist/* deploy/dist-pymod/;
         python -c 'import klayout.db as db; print(dir(db))';
diff --git a/Changelog b/Changelog
index ef0c3ce59..138367007 100644
--- a/Changelog
+++ b/Changelog
@@ -17,6 +17,9 @@
        Performance issue with many layers with width >1
 * Bugfix: https://github.com/klayoutmatthias/klayout/issues/176
        Painting issue with texts
+* Bugfix: https://github.com/klayoutmatthias/klayout/issues/185
+       Hash values available as __hash__ standard method now
+       for Python
 * Bugfix: some potential memory corruption issues fixed
        During the efforts for making the code base compatible
        with MSVC, some potential candidates for memory corruption
diff --git a/MANIFEST.in b/MANIFEST.in
new file mode 100644
index 000000000..8088e14c0
--- /dev/null
+++ b/MANIFEST.in
@@ -0,0 +1,11 @@
+recursive-include src/tl/tl *.cc *.h
+recursive-include src/db/db *.cc *.h
+recursive-include src/gsi/gsi *.cc *.h
+recursive-include src/rdb/rdb *.cc *.h
+recursive-include src/pya/pya *.cc *.h
+recursive-include src/pymod *.cc *.h
+include src/plugins/*/db_plugin/*.cc
+include src/plugins/*/*/db_plugin/*.cc
+include src/plugins/*/db_plugin/*.h
+include src/plugins/*/*/db_plugin/*.h
+recursive-include src/plugins/common *.h
diff --git a/setup.py b/setup.py
index f7b4d2c44..78cc876c2 100644
--- a/setup.py
+++ b/setup.py
@@ -60,10 +60,10 @@ import os
 import platform
 import distutils.sysconfig as sysconfig
 from distutils.errors import CompileError
+import distutils.command.build_ext
 import multiprocessing
 N_cores = multiprocessing.cpu_count()
 
-
 # monkey-patch for parallel compilation
 # from https://stackoverflow.com/questions/11013851/speeding-up-build-process-with-distutils
 def parallelCCompile(self, sources, output_dir=None, macros=None, include_dirs=None, debug=0, extra_preargs=None, extra_postargs=None, depends=None):
@@ -103,6 +103,24 @@ if sys.version_info[0] * 10 + sys.version_info[1] > 26:
     import distutils.ccompiler
     distutils.ccompiler.CCompiler.compile = parallelCCompile
 
+
+from distutils.command.build_ext import build_ext
+_old_get_ext_filename = build_ext.get_ext_filename
+
+
+def patched_get_ext_filename(self, ext_name):
+    r"""Convert the name of an extension (eg. "foo.bar") into the name
+    of the file from which it will be loaded (eg. "foo/bar.so", or
+    "foo\bar.pyd").
+    """
+    filename = _old_get_ext_filename(self, ext_name)
+    # Making sure this matches qmake's default extension .dylib, instead of .so
+    if platform.system() == "Darwin" and '_dbpi' in ext_name:
+        filename = filename.replace('.so', '.dylib')
+    return filename
+
+
+distutils.command.build_ext.build_ext.get_ext_filename = patched_get_ext_filename
 # ----------------------------------------------------------------------------------------
 
 
@@ -121,6 +139,7 @@ class Config(object):
         self.build_platlib = build_cmd.build_platlib
 
         self.ext_suffix = sysconfig.get_config_var("EXT_SUFFIX")
+
         if self.ext_suffix is None:
             self.ext_suffix = ".so"
 
@@ -131,7 +150,10 @@ class Config(object):
         Returns the library name for a given module
         The library name is usually decorated (i.e. "tl" -> "tl.cpython-35m-x86_64-linux-gnu.so").
         """
-        return mod + self.ext_suffix
+        ext_suffix = self.ext_suffix
+        if platform.system() == "Darwin" and '_dbpi' in mod:
+            ext_suffix = ext_suffix.replace('.so', '.dylib')
+        return mod + ext_suffix
 
     def path_of(self, mod):
         """
@@ -149,7 +171,7 @@ class Config(object):
             return []
         else:
             return ["-Wno-strict-aliasing",  # Avoids many "type-punned pointer" warnings
-                    "-std=c++0x",  # because we use unordered_map/unordered_set
+                    "-std=c++11",  # because we use unordered_map/unordered_set
                     ]
 
     def link_args(self, mod):
@@ -191,7 +213,7 @@ class Config(object):
         """
         Gets the version string
         """
-        return "0.26.0.dev1"
+        return "0.26.0.dev4"
 
 
 config = Config()
@@ -201,13 +223,15 @@ config = Config()
 
 _tl_path = os.path.join("src", "tl", "tl")
 
-_tl_sources = glob.glob(os.path.join(_tl_path, "*.cc"))
+_tl_sources = set(glob.glob(os.path.join(_tl_path, "*.cc")))
 
 # Exclude sources which are compatible with Qt only
-_tl_sources.remove(os.path.join(_tl_path, "tlHttpStreamQt.cc"))
-_tl_sources.remove(os.path.join(_tl_path, "tlHttpStreamNoQt.cc"))
-_tl_sources.remove(os.path.join(_tl_path, "tlFileSystemWatcher.cc"))
-_tl_sources.remove(os.path.join(_tl_path, "tlDeferredExecutionQt.cc"))
+# Caveat, in source distribution tarballs from pypi, these files will
+# not exist. So we need an error-free discard method instead of list's remove.
+_tl_sources.discard(os.path.join(_tl_path, "tlHttpStreamQt.cc"))
+_tl_sources.discard(os.path.join(_tl_path, "tlHttpStreamNoQt.cc"))
+_tl_sources.discard(os.path.join(_tl_path, "tlFileSystemWatcher.cc"))
+_tl_sources.discard(os.path.join(_tl_path, "tlDeferredExecutionQt.cc"))
 
 _tl = Extension(config.root + '._tl',
                 define_macros=config.macros() + [('MAKE_TL_LIBRARY', 1)],
@@ -215,7 +239,7 @@ _tl = Extension(config.root + '._tl',
                 libraries=['curl', 'expat'],
                 extra_link_args=config.link_args('_tl'),
                 extra_compile_args=config.compile_args('_tl'),
-                sources=_tl_sources)
+                sources=list(_tl_sources))
 
 # ------------------------------------------------------------------
 # _gsi dependency library
@@ -249,10 +273,12 @@ _pya = Extension(config.root + '._pya',
 # _db dependency library
 
 _db_path = os.path.join("src", "db", "db")
-_db_sources = glob.glob(os.path.join(_db_path, "*.cc"))
+_db_sources = set(glob.glob(os.path.join(_db_path, "*.cc")))
 
 # Not a real source:
-_db_sources.remove(os.path.join(_db_path, "fonts.cc"))
+# Caveat, in source distribution tarballs from pypi, these files will
+# not exist. So we need an error-free discard method instead of list's remove.
+_db_sources.discard(os.path.join(_db_path, "fonts.cc"))
 
 _db = Extension(config.root + '._db',
                 define_macros=config.macros() + [('MAKE_DB_LIBRARY', 1)],
@@ -261,7 +287,7 @@ _db = Extension(config.root + '._db',
                 language='c++',
                 extra_link_args=config.link_args('_db'),
                 extra_compile_args=config.compile_args('_db'),
-                sources=_db_sources)
+                sources=list(_db_sources))
 
 # ------------------------------------------------------------------
 # _rdb dependency library
diff --git a/src/pya/pya/pyaModule.cc b/src/pya/pya/pyaModule.cc
index 9670a0736..ecfb35c3c 100644
--- a/src/pya/pya/pyaModule.cc
+++ b/src/pya/pya/pyaModule.cc
@@ -2687,6 +2687,12 @@ PythonModule::make_classes (const char *mod_name)
                 add_python_doc (*c, mt, int (mid), tl::to_string (tr ("This method is also available as 'str(object)'")));
               }
 
+            } else if (name == "hash" && m_first->compatible_with_num_args (0)) {
+
+              //  The hash method is also routed via the tp_hash implementation
+              alt_names.push_back ("__hash__");
+              add_python_doc (*c, mt, int (mid), tl::to_string (tr ("This method is also available as 'hash(object)'")));
+
             } else if (name == "inspect" && m_first->compatible_with_num_args (0)) {
 
               //  The str method is also routed via the tp_str implementation
diff --git a/src/tl/unit_tests/unit_tests.pro b/src/tl/unit_tests/unit_tests.pro
index 59776da0c..89d63ec6c 100644
--- a/src/tl/unit_tests/unit_tests.pro
+++ b/src/tl/unit_tests/unit_tests.pro
@@ -30,6 +30,7 @@ SOURCES = \
   tlVariant.cc \
   tlXMLParser.cc \
   tlUri.cc \
+  tlStreamTests.cc \
   tlWebDAV.cc \
   tlHttpStream.cc \
   tlInt128Support.cc \
diff --git a/testdata/python/dbTransTest.py b/testdata/python/dbTransTest.py
index 8f7643f45..b3423b01e 100644
--- a/testdata/python/dbTransTest.py
+++ b/testdata/python/dbTransTest.py
@@ -530,6 +530,14 @@ class DBTransTests(unittest.TestCase):
     self.assertEqual(t1.hash() == t3.hash(), False)
     self.assertEqual(t1.hash() == t4a.hash(), False)
     self.assertEqual(t1.hash() == t4b.hash(), False)
+    self.assertEqual(hash(t1) == hash(t2), True)
+    self.assertEqual(hash(t1) == hash(t3), False)
+    self.assertEqual(hash(t1) == hash(t4a), False)
+    self.assertEqual(hash(t1) == hash(t4b), False)
+    self.assertEqual(t1.__hash__() == t2.__hash__(), True)
+    self.assertEqual(t1.__hash__() == t3.__hash__(), False)
+    self.assertEqual(t1.__hash__() == t4a.__hash__(), False)
+    self.assertEqual(t1.__hash__() == t4b.__hash__(), False)
 
     # Transformations can't be used as hash keys currently
     if False: