Add note in CONTRIBUTING.md that some structs need prefix/suffixes

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9ddd792b238c57dae399b19d0d1a7abf86e12181..3cf463ba02e220b7f1e12605398c344fc3d79628 100644 (file)
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -113,6 +113,14 @@ rustup component add clippy
 cargo clippy
 ```
 
+Significant structures that users persist should always have their serialization methods (usually
+`Writeable::write` and `ReadableArgs::read`) begin with
+`write_ver_prefix!()`/`read_ver_prefix!()` calls, and end with calls to
+`write_tlv_fields!()`/`read_tlv_fields!()`.
+
+Updates to the serialized format which has implications for backwards or forwards compatibility
+must be included in release notes.
+
 Security
 --------