HRF Bitcoin Bounty Challenge
Update: This bounty has been claimed, view the winning submission here. Special thanks to all the other open-source contributors and submissions. If you would like your submission to be highlighted please email us.
2 BTC to port the Bitcoin UI Kit from Figma to an open-source Penpot project. The Bitcoin UI Kit serves as a comprehensive set of design components for individuals involved in developing Bitcoin applications.
Currently, the Bitcoin UI Kit is only available in a Figma file format. This is a limitation because it requires the use of proprietary software. To address this issue and increase accessibility, HRF is sponsoring the replication of the Bitcoin UI Kit on Penpot, recognized as the leading open-source alternative to Figma. Penpot is not only free to use, but also allows the setup of self-hosted instances.
1 BTC to deploy a production-ready version 2 payjoin protocol which may send and receive Payjoin transactions without requiring a sender or recipient to operate a public server. The solution should not rely on a trusted third party which could expose user privacy in a non-trivial way. The protocol should be asynchronous and use modern, ideally multiplexed, web standards, without heavy dependencies like Tor, in order to promote widespread adoption. Payjoin requests should make use of BIP-21 unified bitcoin URIs. Some degree of backwards-compatibility and ease of integration with existing BIP-78 payjoin will be taken into consideration as elements of a successful solution.
A protocol specification must be published alongside working software as part of the submission for this bounty.
Update: 1 BTC of this bounty has been claimed by Martti Malmi for his work incorporating this functionality into Iris. The remaining 1 BTC is open to any popular nostr client that can create end-to-end encrypted nostr group chats with an interoperable standard via a merged NIP.
2 BTC for the creation of end to end encrypted group chats powered by any popular Nostr client that does not leak metadata to third parties. Users must be able to chat with at least two other Nostr users. Outside observers must not be able to see the content of messages, the sender/recipient of messages, or the total number of messages between recipients.
1 BTC for a mobile wallet which can send and receive Silent Payments in a private manner without requiring the user to run a full node. This will require a backend which:
The mobile wallet should be:
1 BTC for a human-readable bolt 12 offer generator feature integrated into an iOS or android bitcoin wallet. “Human-readable” means something that can be used on feature phone without QR or copy/paste ability. For example, something that looks like LN address. In order for a wallet to qualify they must meet our internal threshold for monthly active users and other indications of a large user base.
1 BTC for an easy-to-setup self-custodial mobile Lightning address generator integrated into an iOS or android bitcoin wallet. The mobile Lightning address should not require the user to set up their own web server. In order for a wallet to qualify they must meet our internal threshold for monthly active users and other indications of a large user base.
Update: This bounty has been awarded to Bitcoin Tribe for their border wallet functionality and for their React Native library to easily implement border wallet functionality into other Bitcoin wallets.
2 BTC for the integration of border wallet optionality in addition to a seed phrase for a popular iOS or android wallet. The user of the wallet should be easily able to choose to use border wallet functionality to create and memorize their seed. The wallet must allow the user to periodically test their memorized seed to ensure accuracy of memory. The seed words must be BIP-39 compliant, and support either 12 or 24 word seed phrases.
1 BTC for the implementation of a “tap or airdrop to create 2 of 3” multisig functionality between three phones for an open-source iOS or android wallet. The wallet must be self-custodial, with a method for users to recover funds using open-source software outside of the application used to create the multisig. In order for a wallet to qualify they must meet our internal threshold for monthly active users and other indications of a large user base.
1 BTC to a FROST-powered dynamic mobile multisig that allows you to modify the signer set without moving funds to a new address. The wallet must be self-custodial.
A) 0.5 BTC for a fully functional iOS Cashu app
B) 0.5 BTC for a fully functional Android Cashu app
In both iOS and Android cases the wallet must be open source, fully function, and support:
C) 0.5 BTC for an open source Cashu web widget for anonymous paywalled content.
D) 0.5 BTC for Cashu-TS backup restore.
Cashu-TS is a widely-used Cashu wallet library that provides tremendous value to the ecosystem by serving as a basis for developing mobile wallets or web apps. In order for these application to provide a basic level of security for their users, Cashu-TS needs to support a seed phrase backup scheme which allows for a user experience similar to backing up a Bitcoin wallet. The seed phrase backup and the secret derivation scheme should use BIP32 and BIP39 and adhere to the same protocol rules as the reference implementation Cashu Nutshell so that users can restore their balance across different implementations. By enabling backups in Cashu-TS, every wallet and app using it should be able to benefit from it.
0.5 BTC each to the first two (2) open-source self-custodial iOS or Android wallets that add send and receive support for BIP47 payment codes. If a wallet already has this functionality as of July 28, 2023, it is not eligible for this bounty. The purpose of this bounty is to encourage new wallets to add BIP47 support in order to expand the number of privacy options available to Bitcoin users. If a wallet has only send *or* receive functionality as of July 28, 2023, that team can claim a 0.5 BTC credit for adding the other half of the functionality. In order for a wallet to qualify they must meet our internal threshold for monthly active users and other indications of a large user base.
We are launching with an initial set of 10 bounty challenges. More bounties might be added as we go. An individual or team who fully solves any of the ten challenges will be eligible to receive a bounty of 2 BTC.
For transparency: submissions will be shared with external industry experts to help us discern whether submissions meet bounty requirements. HRF will be making decisions in a charitable way for bounty submissions that make a good faith effort to meet the requirements. We will be leaning to the spirit, not the letter, of the law. Individuals and teams are encouraged to contact email@example.com with any questions during the bounty process. HRF retains final approval on allocating prize funds.
The Bitcoin Bounty Challenge will run until December 31, 2024. Any unclaimed bounties will convert into general operating funding for the HRF’s Bitcoin Development Fund on January 1, 2025.
To claim a bounty, an individual or team must submit proof by contacting firstname.lastname@example.org. An individual or team may collect any amount of bounties. Any team is eligible: if a leading wallet maker or for-profit corporation would like to compete, we would be delighted.
The first individual or team to provably solve each challenge or mini challenge will be eligible to receive a BTC grant from HRF.
HRF is a 501(c)3 organization. Any gifts will be considered prizes under US law. Identifying paperwork will need to be filled out by any individuals or entities claiming prizes. If a nym prize-winner would like to remain anonymous, they can instead direct the bounty to another non-profit or Bitcoin initiative of their choice, with HRF’s approval.
Any individual or team participating in HRF’s Bounty Challenge must carefully read and at all times agree with the Terms and Conditions, accessible here.