However, caffeinate fails when I physically close the MacBook lid (unless connected to an external display/power). Looking at your architecture, it seems Lockpaw uses IOPMAssertion from IOKit, which is the same API caffeinate uses.

Does Lockpaw have any workarounds for the lid-closed sleep behavior, or is the primary advantage here combining standard sleep assertions with visual shielding/input blocking? (Either way, solving the 'screen is on and fully accessible' problem of caffeinate is a huge win! Great app.)