I have a busted close-bracket key on my keyboard. Previously, I had used Karabiner to map L-control+open_bracket to close_bracket using a custom rule I wrote in the xml-format used by karabiner.

However, now that I've updated to Sierra, Karabiner is out, and Karabiner elements is in. Karabiner elements uses a JSON format. I tried to create a new rule and stick it in the JSON file:

    "rules": [
             {"manipulators": [
                    {"description": "bracket rule",
                            "from": {"key_code": "open_bracket", 
                                     "modifiers": ["left_control"]
                                    },
                              "to": [{"key_code": "close_bracket",
                                      "modifiers":[]
                                    }] 
                    }         ]
             }]

However, this rule doesn't seem to work the way I'd like it to (it just maps open_bracket to close_bracket). 

Does anyone have an insight into what I'm doing wrong here?

THANKS!