Postmaster Riddle

Hello, everyone

I've made a 7-stage Notpron/dnbhl-style cryptographic puzzle. It involves audio manipulation, PGP, age, AES, steganography and some programming ability.

The intended audience is tech-savvy people who enjoy figuring things out and would like to learn about these concepts interactively. You don't need to be familiar with all of them beforehand because part of the challenge is discovering and learning what you need along the way.

We haven't had any solvers yet, but one person has made it as far as level 6. I don't keep logs, so if you solve it, please reach out and let me know on reddit!

I hope you enjoy it! I plan to keep it online for one year.