Feb 064 min read

Built in 2021

A list of stuff built in 2021 by friedger.btc with the great Stacks community

Clarity Contracts

Deployed the first custom contract on mainnet (badges). It was the attendance badge (POAP) for the Stacks Mainnet Launch event. 2027 NFTs were distributed in several batches of 200 to not make the network crash on the first day.

Wrote the SIP-9 specification and deployed the first SIP-9 contract (beeple). You can read about it here.

Proposed specifications for operable tokens and commission trait used in non-custodial marketplaces. The contracts Loopboom v1 and Megapont Ape Club NFTs show that marketplaces must hold assets in custody.

Deployed the Bitcoin Rocks contract as the first contract on Stacks 2.05. It groups the set of early boom NFTs into its own contract.

Wrote SIP-16 specification. It is the formalization of meta data of fungible and non-fungible tokens based on standards of other blockchains.

Developed Prepaid STX contract. This is a proposal to solve non-custodial bidding where buyers charge their prepaid stx "card" that can be operated by a marketplace.

Friedger Pool and Boomboxes, Catarman Swaps

Friedger Pool as a delegated stacking pool that distributes rewards in Stacks tokens from converted BTC rewards. The first reward cycle was reward #3. It is operated through a sets of command line scripts described in this article. Source code is available at this gitlab repo. To encourage more stacking pools a pool registry was created with the support of Stacks grant 52.

On-chain auditing and payout in wrapped BTC rewards. These were some experiments about how trust in payouts can be reduced by a) reporting BTC reward txs to a stacks smart contract (see details here and here) and then b) payout rewards with a 1:1 wrapped BTC token (see details here). Main learning: On-chain verification does not work in production before 2.1 and wrapped BTCs are worthless if they can't be swapped or traded. Also users with hardware wallets wouldn't be able to use these tokens until a wallet supports both transaction signing and hardware wallets. The work was supported by Stacks grant #121.

Helped building Boom and developed Boomboxes starting in July 2021. It is a way to simplify the life of pool admins because users lock their stx themselves. Caveat, there is no guarantee that the minimum is reached to get at least 1 reward slot. Note, that the final commitment of each cycle can execute by any user in the time window of 100 blocks before the start of the cycle.

Developed and executed Catamaran Swaps. The continued work of BTC tx verification resulted in a set of contracts and a web application to swap assets on the Stacks chain for Bitcoins. These swaps are called Catamaran swaps because both assets are above the water (on-chain) in contrast to submarine swaps. Later, the swap of arbritray NFT and FT was removed for security reasons. In addition, atomic swap contracts for swaps on Stacks only were added, including multi-NFT swaps for Crash Punks.

Developed Custom Boomboxes in late December 2021. These Boomboxes are managed by the Boombox Admin contract and removes the need for users to allow handling stacking for each new Boombox. A Custom Boombox can be created by any user with custom locking periods and defining the pool's reward address.


Ran the Advocate Stacking Pool. The pool rewards Stacks advocates for their acknowledged contributions.

Helped building NFT projects: Stacks Pandas, Megapont Apes, dCards, BTC Rocks, Pops Ice Machine. Discussed with builders of Stacks Pops, Derupt and others in many discord sessions.

Developed Games of PoX. It is an interactive real-life game that demonstrate proof of transfer.

Opened and commented on issues on various git repos and sent pull requests to stacks.js, stacks-blockchain and stack-blockchain-api.

Started to write a SIP for the Stacks authentication protocol and spent many hours to get this P1 bug related to user profiles fixed.

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