Last-minute Halloween costumes for tech nerds

It happens to the best of us — you’ve completely dropped the ball on figuring out a Halloween costume. Naturally, you’ve decided to solve this problem by turning to… TechCrunch? Yeah, sure, why not. I’ve got some ideas.

Here are some last-minute techy Halloween costumes. Effort levels vary.

Recursive self-improvement

AI leaders like Dario Amodei and Sam Altman have expressed their fears that AI is developing too quickly, but if AI models become capable of “recursive self-improvement,” they’ll be able to advance on their own without human intervention, rendering any efforts to “pace the frontier” futile.

I’m not sure how to visually represent the idea of an AI building itself, but you could really lean into the “self-improvement” part and forget the “recursive” aspect — it’s a last-minute Halloween costume. You don’t need to try that hard.

Dress as the version of yourself you imagine becoming every year when you make New Year’s resolutions. Carry around a self-help or productivity book like “Atomic Habits” or anything by Malcolm Gladwell, a yoga mat, and a huge bottle of water. Leave in the middle of the party to “go to therapy” when you actually just want to go home. Brag to people about how good your Oura Ring’s sleep score is.

You are the embodiment of someone trying to better themselves. You are recursive self-improvement.

A deceptively cute AI agent

Meta and OpenAI both recently launched AI assistants with creepily cute avatars. It’s almost Elizabeth Holmes-esque — they look innocent, so you underestimate their potential to cause disaster. (While we’re talking about her, you’re only allowed to do the black turtleneck Holmes costume if you’re a natural blonde, or if you have a blonde wig.)

What you’re going to do is make yourself look big and fluffy. Maybe you have a poofy puffer jacket, or maybe you can find some colorful feather boas to wrap yourself in. Add a distinctive hat, glasses, or other accessory to make yourself look more like a ChatGPT Dot. If you have a colorful shirt and matching bottoms, that also works.

Throughout the night, ask people if you can obtain read/write access to their Gmail.

A guy who is actively recording you with Meta glasses

Whether you call them “pervert glasses” or not, we should all be able to agree that it would be really spooky if someone just started recording you without your consent — perfectly in keeping with the Halloween spirit.

Just grab a pair of glasses — or buy a cheap pair somewhere convenient — and attach a big red or white circle to one lens, mimicking the red recording light. If you want to make the costume extra creepy (or, if you can’t make a big circle sticker), you can just wear normal glasses and say that you’re ‘guy recording with the light covered up.’ Please, just don’t actually record people without their consent while you wear this costume.

Mark Zuckerberg wearing a vaguely unsettling T-shirt

While we’re at it, Mark Zuckerberg’s fashion has been pretty recognizable lately. He’s been wearing a lot of slightly oversized, boxy black T-shirts.

It may be hard to replicate the black-text-on-black-shirt style he gravitates toward, but you could attach a piece of paper to yourself that says “Building is my love language.”

If you feel confident in your Latin pronunciation, you could go for something actually scary, like the time he wore a shirt that said “Aut Zuck aut nihil,” which means “Either Zuck or nothing.” It’s a little ominous.

An AI usage limit notification

For some people, there’s nothing scarier than running out of Claude tokens.

Grab a piece of cardboard, print out screenshots of notifications telling you that you’ve reached your usage limit, and go spook some vibe-coders. I’ve illustrated this idea using an edited stock photo. You don’t have to dress like you work at Hot Topic — that’s just the model in the image.

A PHP vulnerability

The scary PHP-opocalypse is fresh in our memory — it was only last week that AI unearthed critical PHP flaws that could’ve been catastrophic for the internet. The fear that web developers felt is still palpable, making it a good Halloween costume: You are a PHP vulnerability.

Here’s what you’re going to do. Buy a T-shirt and a sharpie, and write PHP on it. Keep it simple.

What about the vulnerability part? You’re going to have to commit to the bit. All night, you’re going to talk to your friends about your feelings. Actually bare your emotions. Talk about how your recent loss of a loved one made you remember how fragile life can be. If making yourself vulnerable kills the vibe, just pretend it was part of the Halloween costume and that you’re really cool and fun and never feel sad ever.

Bryan Johnson

The costume explains itself.

Bryan Johnson, a second time

Couples costume alert!

Maybe you have more than one Halloween party to go to this weekend, but you want your various costumes to stick to a specific theme. Once you’ve got your sleepy time getup sorted, it’s time to prep your second costume portraying the controversial biohacker: GLP-Bryan.

Johnson wrote on X earlier this year: “I frequently lay on top of Kate with all of my bodyweight. The deep pressure calms her nervous system, quiets racing thoughts, and releases oxytocin which lowers cortisol. We call it GLP-Bryan.”

Naturally, people were confused, so he shared an image to demonstrate.

Yes, this will be hard to reproduce as a Halloween costume, but if you’ve run out of time to buy anything, this one will do. Just wear a T-shirt and jeans, which you probably already own. It will be weird to lie on top of your partner in the middle of a party. Really weird. But that’s what you get for waiting until now to figure out a costume.

lmk if you want a video demo https://t.co/9g95g9y7D3 pic.twitter.com/FiYjSs86nm

— Bryan Johnson (@bryan_johnson) September 24, 2026

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