diff --git a/platformio.ini b/platformio.ini
index fd850316..4179d2f7 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -118,7 +118,9 @@ build_flags =
 
 [env:esp32]
 extends = common_embedded
-platform = espressif32
+# Pinned: 8.0.0 (2026-10-19) pulls a GCC whose stricter -Wformat-truncation analysis
+# breaks -Werror builds (see the espressif32 8.x migration tracking issue).
+platform = espressif32@7.1.3
 board = esp32dev
 upload_speed = 460800 
 monitor_filters = esp32_exception_decoder