README: declare Go 1.8+ support only

prebid · Mar 4, 2018 · cad7d7d · cad7d7d
1 parent 089b8f5
commit cad7d7d
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/README.md b/README.md
@@ -7,6 +7,12 @@ Also includes [OpenRTB](https://www.iab.com/guidelines/real-time-bidding-rtb-pro
 - [5 Native Ad Response Markup Details](native/response/)
 - [7 Reference Lists/Enumerations](native/)
 
+**Requires Go 1.8+**
+
+Go 1.8+ is needed for proper `Ext json.RawMessage` marshaling: non-pointer `json.RawMessage` is marshaled as base64 string prior to Go 1.8.
+
+This library uses `json.RawMessage` since [v10.0.0](https://github.com/mxmCherry/openrtb/releases/tag/v10.0.0).
+
 # Using
 
 ```bash