diff --git a/CHANGELOG.md b/CHANGELOG.rst
similarity index 65%
rename from CHANGELOG.md
rename to CHANGELOG.rst
index 6cfc446..62101ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.rst
@@ -1,14 +1,18 @@
-# v0.3.0
+v0.3.1
+=============
 * Current version
+* Add systematic module, with routine to simulate detector crosstalk.
+* Fix bugs in the detector/SQUID labeling (instrument module).
 
-
-# v0.2.0
+v0.2.0
+=============
 * Add Fortran scripts and Makefile for the compilation.
 * Add detector pointing and TOD modules.
 * Doc contains end-to-end example (without systematic effect).
 * Fix many bugs related to absolute imports (py 2 vs 3) and failed tests in doctest.
 
-# v0.1.0
+v0.1.0
+=============
 * First version of the repo (public)
 * Add instrument and scanning strategy modules.
 * Release public version.
diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
new file mode 100644
index 0000000..ab042c0
--- /dev/null
+++ b/CONTRIBUTING.rst
@@ -0,0 +1,19 @@
+================
+Contributing to S4CMB
+================
+
+Issues
+=============
+Feel free to submit issues and enhancement requests.
+
+Contributing
+=============
+In general, we appreciate the "fork-and-pull" Git workflow.
+
+* Fork the repo on GitHub
+* Clone the project to your own machine and set up a new branch
+* Commit changes to your branch
+* Push your work back up to your fork
+* Submit a Pull request so that we can review your changes
+
+NOTE: Be sure to merge the latest from "upstream" before making a pull request!
diff --git a/README.rst b/README.rst
index 4c964de..95bd48d 100644
--- a/README.rst
+++ b/README.rst
@@ -49,7 +49,7 @@ Just add in your bashrc:
 ::
 
     s4cmbPATH=/path/to/the/package
-    export PYTHONPATH=$PYTHONPATH:$s4cmbPATH:$s4cmbPATH/instrument
+    export PYTHONPATH=$PYTHONPATH:$s4cmbPATH
 
 Examples
 =============
diff --git a/setup.py b/setup.py
index 608d394..3b5f8c7 100644
--- a/setup.py
+++ b/setup.py
@@ -40,7 +40,7 @@ def configuration(parent_package='', top_path=None):
 
     setup(
         name='s4cmb',
-        version='0.3.0',
+        version='0.3.1',
         url='https://github.com/JulienPeloton/s4cmb',
         download_url='',
         license='GPL-3.0',