diff --git a/CHANGELOG.md b/CHANGELOG.md
index 58622333..9572654a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,10 +1,11 @@
 CHANGELOG
 ---------
 
-dev
+v0.2.1 (23/5/18)
 ----------
-
+ - move theano backend out of master branch
  - more efficient training with --token_batch_size
+ - data iterator for multilingual training (#67)
 
 v0.2 (17/12/2017)
 ----------
diff --git a/README.md b/README.md
index 6d4e133b..56c2d59e 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,8 @@ Attention-based encoder-decoder model for neural machine translation
 This package is based on the dl4mt-tutorial by Kyunghyun Cho et al. ( https://github.com/nyu-dl/dl4mt-tutorial ).
 It was used to produce top-scoring systems at the WMT 16 shared translation task.
 
+This version of Nematus is based on Theano. The main development work is done on the Tensorflow version in the master branch.
+
 The changes to Nematus include:
 
  - new architecture variants for better performance: