Nexus market mirrors, as published on this site
nexusb2l7fmqnefwphyy7m5zjhlkytlbo7qbb5lu5dlczr3azgii2gyd.onionnexusma2iqgauqqvjcgds4ckv5xbf272tkfagq4epojjhsgleqpwxiqd.onionnexusabcd6tyfhdwilyitaqiri6tisj2v2hueyjuj6qkvd6azvi5tuqd.onionPublished as supplied. This site does not probe an onion, so nothing here is a claim that a given address opens for you right now.
A QR code on a sticker is a printed square with a grid of black and white cells that decodes to one string. Readers use it because a phone camera reads it without typing. The sticker itself is a physical object that sits on a physical surface.
What it is
A QR code encodes bytes. A sticker with a QR on it is the code plus paper plus adhesive. A reader points a phone camera at the sticker, the phone decodes the cells to text and offers the text to open. What the text is depends entirely on what was fed to the encoder when the sticker was printed.
A QR does not know what the string is meant to be. It stores whatever it was given. If the encoder was fed the wrong string, every scan for the life of the sticker returns the wrong string. If the encoder was fed the right string with a trailing space, every scan returns the right string with a trailing space.
Lifeline
- On a screen
- Printed on a label
- Worn, peeled or replaced
What the code keeps
- The bytes the encoder was given, byte for byte, until the label wears enough that the decoder cannot read cells.
- The ability to correct a modest amount of damage, because the code was printed with an error correction level that lets the decoder rebuild missing cells.
- The independence from a keyboard, because the reader does not type any character and cannot introduce a typo at the scan.
- The invisibility of the string to a person who is not scanning, because a QR grid does not read as text to the human eye.
What the code loses
- The chance to catch an encoder mistake, because once the sticker is printed the code is frozen.
- The link back to what the reader thought they encoded, because the sticker only shows the grid and not the text.
- The freedom from a physical world, because a sticker can be peeled, replaced or overprinted by someone with access to the surface it is on.
- The chance to update, because a rotated address means a reprinted sticker, not a rewritten line.
What the encoder ate
A common failure at print time is that the encoder was pointed at a page rather than at a copy of the string. A page has a header, a footer and a paragraph before the address. If any of that ended up in the input, the QR now decodes to a paragraph that contains the address instead of the address alone. The decoder on the phone shows the whole paragraph. Some readers copy the whole paragraph across.
Another failure is that the encoder was given a string that ended in a punctuation mark or a newline. The mark got encoded. The scan returns a string with a trailing dot or a leading space. A browser bar that is given a trailing dot on a .onion may resolve it, may not, or may resolve to a different site.
What the reader sees
A phone camera scanning a QR usually shows a banner with the decoded text and a tap to open. The reader who taps without reading is trusting the sticker. The reader who reads the banner first can see if the string looks right. This is the one check the QR path offers, and it is only available for one second between the scan and the opening.
A banner that is truncated is a banner that hides half the string. A camera app that only shows the first thirty characters is a camera app that does not show the vanity tail. A reader can tap the banner to expand it before opening. A reader who does not tap accepts what the camera thought was interesting.