We’re excited to welcome Martin Habovštiak to Bitcoin is RETRO! 25th April 2026!

Martin Habovštiak: How I made a Bitcoin transaction that is in its entirety an image file

“The BIP-110 supporters claim, among other funny things, that it matters whether the data in the Bitcoin time chain is contiguous or not and that it is impossible to put contiguous data longer than 520B into Bitcoin without using an output which has a script starting with OP_RETURN. To prove them laughably wrong, I have put over 66kB image file into the chain that is not only contiguous but also forms an entire valid transaction. Thus one can simply save the transaction as an image and open it with a standard image viewer. In addition, the transaction avoids the features that the BIP-110 supporters claim enable embedding data into the chain. A BIP-110-compliant version of the transaction was made as well.

In the talk I will explain how it’s possible to not only bypass the supposed 520B limit on contiguous data but also make an entire transaction into a valid image file.“

Bitcoin je RETRO! tickets: https://pay.cypherpunk.today/plugins/FhgdSzrmhbgrR1v64Y4EdpVxedKN3JhRnKT6mqh62QMi/ticket/public/event/199f6655-c62a-4f26-b24e-95fa2905f148/summary/tickets