HN

Comments (36)

• 0xbadcafebee
  In DevOps (and Lean, TPS) the more advanced form of this is the Poka-Yoke (https://en.wikipedia.org/wiki/Poka-yoke). Poka-yokes don't just add safety, they also guide the human away from making a mistake.The canonical example is the automatic shift knob in a car. The shift knob is designed to 1) prevent you from accidentally shifting all the way back into reverse without pressing the shift button, and 2) prevents you from leaving park or neutral without depressing the brake pedal. This way you don't damage the drivetrain or accidentally cause the car to roll forward/backward.Poka-yoke is a form of defensive design (https://en.wikipedia.org/wiki/Defensive_design). For a beautiful example of defensive design, see the average electric kettle. If water boils over the top it won't short the device, if it boils dry it'll stop operating, the handle and body are plastic to prevent burning yourself, the handle is ergonomic to make carrying 1.5L of sloshing boiling water not cause you to spill it, the cord is detached from the kettle so you don't yank the cord and spill the boiling water, the switches are located on the bottom away from hot steam, and the lids usually lock while in operation, again to prevent damage from spillage or steam. It's the simplest and safest possible way to boil water, and it's $20.
• davidshepherd7
  That page is copied verbatim from https://unsung.aresluna.org/molly-guard-in-reverse/ (which is linked at the top). The original page also has much better formatting.
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  JoshTriplett
  There's a great piece of software called "molly-guard", which intercepts calls to "poweroff" and "reboot" and similar. It checks if it's being invoked via an SSH session, and if so, it asks you to type the name of the system you're shutting down. That way, you never accidentally shut down a remote server when you meant to shut down your own system (or a different server).
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  evanjrowley
  I'm reminded of this legendary HN comment: https://news.ycombinator.com/item?id=16530398
• wibbily
  Fun: the “Molly” in question is Ed Krol’s daughter - he’s the guy who wrote the Whole Internet User’s Guide and Catalog.https://en.wikipedia.org/wiki/Ed_Krol
• meelford
  I personally know a guy who shut down an oil factory by pressing the molly guard button, just because the button looked interesting.
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  jiehong
  Oh! Then perhaps the long press required for the iPhone’s action button to trigger is a Molly guard!Also, perhaps `rm` should be molly guarded to move things to the trash on all systems by default, and delete only if forced to by a flag.Note: I’d have expected Molly to be a cat, because they tend to be pretty good at disrupting things in my experience.
• itayd
  best molly-guard depicited in "The Good Place": https://www.youtube.com/watch?v=etJ6RmMPGko
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  donut
  Sometimes a pop-up appears that I blindly accept because I happen to be typing something with spaces. Wish that button was protected somehow.
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  fainpul
  Just please don't start adding molly-guards to your software. The concept only makes sense in the physical world, e.g. where the "important button", that you might never have to press, needs to be in reach all the time. In software, there are better solutions.
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  jiehong
  I do wish those were a thing on flat touch sensitive induction cooktops! (For all those pesky water droplets causing the cooktop to error out and turning itself off)
• buf
  Fun random fact, Eventbrite was first a security company called Molly Guard. I spent years cleaning out the 'mg-' prefixes from the code.
• hyperhello
  “Mollyguarding” sounds like a great derogation of unnecessary safety measures. Stop mollyguarding me!
• Shadowmist
  I've been looking for this!
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  yolosollo
  [dead]