Summary: JoinMarket matters because it treats CoinJoin coordination as a market, not a waiting room. Makers keep UTXOs online and sell immediate participation; takers pay to assemble a join when they want it. Fidelity bonds make that market harder to sybil by forcing makers to park real bitcoin behind a durable public identity. That is the reason to keep the note: the control surface is maker inventory, taker selection, messaging access, and bond-weighted reputation, not privacy wallet branding. It is a baseline mechanism note, not a current flagship wallet.
What it does:
Implements Bitcoin CoinJoin creation through a maker-taker market where takers initiate joins and makers advertise offers for different amount ranges and fees
Lets makers run always-on yield-generator bots that quote prices, ranges, and fee policies in exchange for participating in CoinJoins and earning revenue
Lets takers choose counterparties from the market and create CoinJoins at the time and size they want rather than waiting for a coordinator to batch users into fixed rounds
Uses fidelity bonds to make maker identities expensive to sybil, with makers locking bitcoin under timelock scripts and takers preferring higher-valued bonds with high probability
Supports multiple privacy-management features around the CoinJoin workflow, including mixdepth separation, tumbler automation, coin control, and PayJoin support
Separates the participant-messaging daemon layer from wallet/application logic so client software can use JoinMarket’s coordination protocol without inheriting the full wallet stack
Publishes orderbook data and maker availability through the project’s messaging and orderbook tooling rather than through a single branded web coordinator
Key claims:
The README is explicit that JoinMarket exists because CoinJoin is not only a software problem but an economic one: the right coins have to be available in the right amounts at the right time, so the project creates a market to allocate that privacy liquidity.
The maker-taker split is the main reusable mechanism. Makers stay online and sell immediate participation, while takers pay for on-demand CoinJoin creation. That is a different control surface from wallet-run waiting rooms, centrally scheduled mixes, or fixed-size pool coordinators.
The yield-generator docs make clear that market supply is operationally real, not abstract. Makers need a local full node, always-on connectivity, meaningful balances, and competitive pricing, and taker software remembers counterparties that offered poor performance.
Fidelity bonds are the key second-layer mechanism. The docs describe them as deliberately sacrificing bitcoin value, usually by CLTV timelock, so takers can weight selection toward costly maker identities. This exposes sybil resistance as capital commitment plus selection policy, not just CAPTCHA or coordinator screening.
The fidelity-bond docs also reveal an important asymmetry: long-term holders can create strong maker identities relatively cheaply in time-value terms, so JoinMarket’s sybil defense is partly a market for patient capital rather than purely a fee market.
Payjoin is the useful upstream contrast: it attacks payment-time linkage during ordinary transaction construction instead of building a standing market for mixing liquidity.
The architecture notes are useful because they show JoinMarket is not just a wallet. The project explicitly separates inter-participant messaging from wallet actions via a daemon/client split, reducing backend trust and making alternate client implementations easier.
The repository’s archived status matters. JoinMarket still clears the corpus bar because it gives a historically important, mechanism-clean baseline for privacy-liquidity markets, fidelity-bond sybil resistance, and maker inventory economics even if the reference implementation is no longer an actively evolving flagship.
Whitepaper: No single canonical JoinMarket whitepaper surfaced in this pass. The strongest primary materials were the archived official repository README and docs for usage, yield generators, fidelity bonds, orderbook exposure, and architecture; see ../whitepapers/joinmarket-primary-sources-2026-05-15.md.