diff --git a/CHANGELOG b/CHANGELOG
index 661581433..638c36121 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -17,6 +17,8 @@ Yosys 0.9 .. Yosys 0.9-dev
     - Added automatic gzip decompression for frontends
     - Added $_NMUX_ cell type
     - Added automatic gzip compression (based on filename extension) for backends
+    - Improve attribute and parameter encoding in JSON to avoid ambiguities between
+      bit vectors and strings containing [01xz]*
 
 Yosys 0.8 .. Yosys 0.8-dev
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