caps-karabiner.json

{
    "description": "Capslock: short press toggles language, hold or with modifiers acts as command+control+option+shift",
    "manipulators": [
        {
            "conditions": [
                {
                    "input_sources": [{ "language": "en" }],
                    "type": "input_source_if"
                }
            ],
            "from": {
                "key_code": "caps_lock",
                "modifiers": { "optional": ["any"] }
            },
            "to": [
                {
                    "key_code": "left_shift",
                    "modifiers": ["left_command", "left_control", "left_option"]
                }
            ],
            "to_if_alone": [{ "select_input_source": { "language": "ru" } }],
            "type": "basic"
        },
        {
            "conditions": [
                {
                    "input_sources": [{ "language": "ru" }],
                    "type": "input_source_if"
                }
            ],
            "from": {
                "key_code": "caps_lock",
                "modifiers": { "optional": ["any"] }
            },
            "to": [
                {
                    "key_code": "left_shift",
                    "modifiers": ["left_command", "left_control", "left_option"]
                }
            ],
            "to_if_alone": [{ "select_input_source": { "language": "en" } }],
            "type": "basic"
        }
    ]
}