diff --git a/CHANGELOG.txt b/CHANGELOG.txt
index 34d92fa480b0754be3153fa21a1c1403fec7e8e9..dc4b0a416dbd06bc58067bc353584b68b697204d 100644
--- a/CHANGELOG.txt
+++ b/CHANGELOG.txt
@@ -1,4 +1,4 @@
-Changes in Release 1.X.0
+Changes in Release 1.9.0
 --------------------------------------------------------------------------------
 
  * Improved compare-structures action (chain mapping handling and documentation).
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 74a3348880146b72ffb3f3e045ef4502110eea98..065174c38250fcf10e35959228716be55a9a2f0b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,7 +6,7 @@ cmake_minimum_required(VERSION 2.6.4 FATAL_ERROR)
 project(OpenStructure CXX C)
 set (CMAKE_EXPORT_COMPILE_COMMANDS 1)
 set (OST_VERSION_MAJOR 1)
-set (OST_VERSION_MINOR 8)
+set (OST_VERSION_MINOR 9)
 set (OST_VERSION_PATCH 0)
 set (OST_VERSION_STRING ${OST_VERSION_MAJOR}.${OST_VERSION_MINOR}.${OST_VERSION_PATCH} )
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${PROJECT_SOURCE_DIR}/cmake_support)
diff --git a/singularity/README.rst b/singularity/README.rst
index f90cf47553a96a3bf9eaab68970fcf91f2b109ff..7dbc72271e821a69dcafaa066a5e8940c4ae45b3 100644
--- a/singularity/README.rst
+++ b/singularity/README.rst
@@ -9,7 +9,7 @@ In order to build OST Singularity image:
 .. code-block:: bash
 
   cd <OST ROOT>/singularity
-  sudo singularity build ost.img Singularity.1.8.0
+  sudo singularity build ost.img Singularity.1.9.0
 
 .. note::
 
diff --git a/singularity/Singularity.1.8.0 b/singularity/Singularity.1.9.0
similarity index 99%
rename from singularity/Singularity.1.8.0
rename to singularity/Singularity.1.9.0
index cf3e3813f5a36ceb0b17e46ffcdd6d1159d27c12..f4d5a7e339380e1a663c944670315642f2dcf876 100644
--- a/singularity/Singularity.1.8.0
+++ b/singularity/Singularity.1.9.0
@@ -17,7 +17,7 @@ export CPUS_FOR_MAKE=8
 export PYTHONPATH="/usr/local/lib64/python2.7/site-packages:${PYTHONPATH}"
 # When changing OPENSTRUCTURE_VERSION make sure to change it also in the
 # environment section of singularity recipe (this file).
-export OPENSTRUCTURE_VERSION="1.8.0"
+export OPENSTRUCTURE_VERSION="1.9.0"
 export OPENSTRUCTURE_SHARE="/usr/local/share/ost"
 export MSMS_VERSION="2.6.1"
 export OPENMM_VERSION="7.1.1"
@@ -223,7 +223,7 @@ cd /home
 # ENVIRONMENT
 ##############################################################################
 export OST_ROOT="/usr/local"
-export OPENSTRUCTURE_VERSION="1.8.0"
+export OPENSTRUCTURE_VERSION="1.9.0"
 export OPENMM_LIB_PATH=/usr/local/openmm/lib/
 export PYTHONPATH="/usr/local/lib64/python2.7/site-packages:${PYTHONPATH}"
 export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/usr/local/lib64:${OPENMM_LIB_PATH}"