diff --git a/src/sandbox/opencode.sh b/src/sandbox/opencode.sh
index 8f8c66c..2545fbd 100644
--- a/src/sandbox/opencode.sh
+++ b/src/sandbox/opencode.sh
@@ -3,6 +3,17 @@
 # SPDX-License-Identifier: MPL-2.0
 
 function sandbox_setup_opencode() {
+    # If there is an opencode config then mount it into the container
+    #
+    # NOTE: older versions of opencode use config.json
+    if [ -f "$HOME/.config/opencode/config.json" ]; then
+        # Ensure parent of mounted opencode folder exists
+        # otherwise .config is root in the container
+        mkdir -p "$PERSIST_FOLDER/home/.config/opencode"
+
+        CONTAINER_RUN_ARGS+=(--volume="$HOME/.config/opencode/config.json":"$HOME/.config/opencode/config.json":ro)
+    fi
+
     # If there is an opencode config then mount it into the container
     if [ -f "$HOME/.config/opencode/opencode.json" ]; then
         # Ensure parent of mounted opencode folder exists