diff --git a/platformio.ini b/platformio.ini
index 9faf1dd..e32f0fd 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -26,6 +26,8 @@ lib_deps =
     jgromes/RadioLib @ 7.8.1
     esphome/wireguard @ 0.4.8
     ewpa/LibSSH-ESP32 @ 5.10.0
+    ; WireGuard brings libsodium in; 1.10021.12 defines crypto_sign_ed25519_open as LibSSH does, and the two do not link
+    esphome/libsodium @ 1.10021.11
 test_ignore = *
 ; Smaller TLS buffers (M2): the framework is rebuilt with these settings (pioarduino "hybrid
 ; compile"). Receive stays 16 KB (servers send full TLS records); send drops to 4 KB (IRC lines are