Skip to content

Grin's Story


On Mon Aug 01 2016 a user named majorplayer logged into the #bitcoin-wizards IRC channel, dropped a text file hosted on a Tor server and then disappeared. The document1 was titled MIMBLEWIMBLE and authored under the pseudonym Tom Elvis Jedusor. It described a protocol which is both private and extremely lightweight.

Tom Elvis Jedusor is the French name for Tom Riddle (Lord Voldemort) from the Harry Potter book series. Mimblewimble is a tongue-tying spell.

-!- majorplayer [...] has joined #bitcoin-wizards
<majorplayer> hi, i have an idea for improving privacy in bitcoin. my friend who
knows technology says this channel would have interest
-!- majorplayer [...] has quit [Client Quit]

Its title:

Tom Elvis Jedusor
19 July, 2016

The following day, users nsh and andytoshi (Andrew Poelstra) began discussing the idea proposed in the paper. The anonymous writer left several un-answered questions in the document, along with a general lack of details, so there was much to discuss. The conversation included a memorable moment:

<nsh> gotta be some way this is sneaky, otherwise it's too good to be true...
<andytoshi> hah, yeah, i know the feeling

On Oct 10 2016, Andrew Poelstra published a follow-up paper2 about Mimblewimble, which introduced several refinements to the original proposal and describes further its technical details.


On Oct 20 2016, a pseudonymous developer using the name Ignotus Peverell, announced in the bitcoin wizards IRC channel that he began work on a minimal implementation of the protocol, which he named Grin.

Ignotus Peverell is the wizard who was gifted the Cloak of Invisibility by Death.
Grin is short for the Gringotts Wizarding Bank.

-!- igno_peverell [~user@] has joined #bitcoin-wizards
<igno_peverell> I have a minimal implementation of MimbleWimble available. It's very far from complete but has the basics, included the summing of Pedersen commitments:
<igno_peverell> Any feedback or review is greatly appreciated. Thanks!

Igno was joined on GitHub by other developers who took interest in the project, several of them bearing pseudonyms of other Harry Potter characters.

While Mimblewimble serves as the foundation to a blockchain, it constitutes a relatively small part of a complete cryptocurrency, and many choices were yet to be made. Thus, began the journey to create a full implementation. A community of contributors and users slowly started to form around grin.


Grin's genesis block was mined on January 15th, 2019. It was, and still is, young and experimental. It currently goes through rapid changes, as its first 2 years include agreed-upon hardforks in 6-months intervals.

Several months after launch, Ignotus Peverell disappeared and has yet to return.

Developers distributed around the world are contributing to build grin, some of them funded by donations to work on the project full-time. Development will always remain completely transparent and open for anybody to join.