diff --git a/CHANGES.rst b/CHANGES.rst
index 8650312c..fb3fa705 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -8,6 +8,29 @@
 wxPython Changelog
 ==================
 
+4.0.1 Lemonade
+--------------
+* 2-Feb-2018
+
+PyPI:   https://pypi.python.org/pypi/wxPython/4.0.1
+Extras: https://extras.wxPython.org/wxPython4/extras/
+Pip:    ``pip install wxPython==4.0.1``
+
+This release is a quick hot-fix of some issues discovered in 4.0.0 just after
+the release, plus a bit of  low-hanging fruit that was easy to squeeze in too.
+Changes in this release include the following:
+
+* A fix for a segfault that happens upon startup on newer linux releases. (#648)
+
+* Set LD_RUN_PATH for the wxWidgets part of the build so the wx libs that are
+  loaded by other wx libs can be found successfully. (#723)
+
+* Use wxApp::GetInstance to check if there is an existing wxApp object. (#720)
+
+
+
+
+
 4.0.0 "The Phoenix Takes Flight!"
 ---------------------------------
 * 31-Jan-2018
diff --git a/build.py b/build.py
index fa1efb09..41ed39ac 100755
--- a/build.py
+++ b/build.py
@@ -1280,6 +1280,12 @@ def cmd_build_wx(options, args):
     if options.extra_make:
         build_options.append('--extra_make="%s"' % options.extra_make)
 
+    if not isWindows and not isDarwin and not options.no_magic and not options.use_syswx:
+        # Using $ORIGIN in the rpath will cause the dynamic linker to look
+        # for shared libraries in a folder relative to the loading binary's
+        # location. Here we'll use just $ORIGIN so it should look in the same
+        # folder as the wxPython extension modules.
+        os.environ['LD_RUN_PATH'] = '$ORIGIN'
 
     try:
         # Import and run the wxWidgets build script
diff --git a/buildtools/version.py b/buildtools/version.py
index e0795e9a..e5f554f3 100644
--- a/buildtools/version.py
+++ b/buildtools/version.py
@@ -26,7 +26,7 @@ VER_MAJOR        = 4
 VER_MINOR        = 0
 VER_RELEASE      = 1
 
-VER_FLAGS        = "a1"     # wxPython release flags
+VER_FLAGS        = ""     # wxPython release flags
 
 # The VER_FLAGS value is appended to the version number constructed from the
 # first 3 components and should be set according to the following patterns.
diff --git a/demo/version.py b/demo/version.py
index c0c68530..7d852726 100644
--- a/demo/version.py
+++ b/demo/version.py
@@ -1,3 +1,3 @@
 # This file was generated by wxPython's wscript.
 
-VERSION_STRING = '4.0.0'
+VERSION_STRING = '4.0.1'
diff --git a/ext/wxWidgets b/ext/wxWidgets
index 46259c14..c3441c5a 160000
--- a/ext/wxWidgets
+++ b/ext/wxWidgets
@@ -1 +1 @@
-Subproject commit 46259c14ecf8c774db203a425524d7889fbecba3
+Subproject commit c3441c5aaf4a53d4ed97ff538ba768f9a2ee76d0
diff --git a/src/wxpy_api.sip b/src/wxpy_api.sip
index c754b1c4..81b2f7ba 100644
--- a/src/wxpy_api.sip
+++ b/src/wxpy_api.sip
@@ -439,7 +439,7 @@ PyObject* i_wxVariant_out_helper(const wxVariant& value)
 PyObject* wxPyNoAppError = NULL;
 
 bool i_wxPyCheckForApp(bool raiseException) {
-    if (wxTheApp != NULL)
+    if (wxApp::GetInstance() != NULL)
         return true;
     else {
         if (raiseException)
diff --git a/vagrant/README.rst b/vagrant/README.rst
index 4583f4f0..016e2ea7 100644
--- a/vagrant/README.rst
+++ b/vagrant/README.rst
@@ -50,7 +50,7 @@ release or the snapshots server can be used. With that file in place then a
 build for a specific distro can be done with just a few vagrant commands, for
 example::
 
-    cd vagrant/ubuntu-16.04-x64
+    cd vagrant/ubuntu-16.04
     vagrant up
     vagrant ssh -c "scripts/build.sh ubuntu-16.04"
     vagrant halt