1 files changed, 3 insertions, 0 deletions

diff --git a/README.md b/README.md
index 8757dc8..c304f23 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,9 @@ it will eat-your-data.
 
 ### Dependencies
 
+While (temporarily?) using Cargo's `[patch]` feature to patch sodiumoxide,
+builds require Rust 1.21 (stable circa Oct 2017).
+
 Requires libsodium-dev system-wide (for now).
 
 Notable Rust Libraries: