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Henrik Selje Bygnes

Personal notebook

Henrik Selje Bygnes

Hacking as a way to understand systems, people, and myself.

Everything can be broken. Most things can be fixed. I write to find the difference.

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Caffeine Was My Gateway Drug

·13 mins
Caffeine did not cause anything. It taught me that the brain I woke up with wasn’t the brain I had to keep, and that lesson generalised. A personal account with the pharmacology attached, including why three tablespoons of grounds per cup felt almost identical to low dose amphetamine.

Steroids and SARMs: Making a Bad Decision Properly

·52 mins
The message I keep getting, answered once and properly: hormones, conversion pathways, compounds, bloodwork, injection technique, PCT, the cardiovascular data, and how to find out what is actually in the vial.

Your Fødselsnummer Is Not a Password

·10 mins
The Norwegian national ID number is treated as a secret and structurally cannot be one. A walk through the mod-11 arithmetic, a count of what a birthday actually leaves, and why 2032 is an admission.

AI Killed My Favourite Hobby

·5 mins
I took second place in Cyberlandslaget 2025 and then quit CTFs. Not because I stopped loving the puzzles, but because AI changed what the leaderboard measures. On losing a hobby to the tool I use every day.

Amphetamine: Cleaning Up After Someone Else's Chemistry

·36 mins
A harm reduction guide to street amphetamine: reading contamination by eye, the acetone wash, the purity paradox that puts people in ambulances, reagent and lab testing, routes, interactions, and what to actually measure.

The Man Who Got Addicted to Heroin in Real Time

·11 mins
BloodshotEyes came to a Norwegian forum asking how to inject heroin. Over the next four years, strangers watched his experiment become dependence, relapse, treatment, and despair.