COMIT — BTC ↔ XMR Atomic Swap

The protocol home and lineage page for the canonical Bitcoin ↔ Monero atomic-swap stack. COMIT Network published the open cryptographic protocol (HTLCs + Scriptless Scripts) and authored the original `xmr-btc-swap` Rust reference implementation; the COMIT team has since stepped back from active maintenance and the community fork — now branded EigenWallet — is the working continuation. This entry exists to document the lineage so the technology, the research, and the active product don't get conflated. If you want to actually swap BTC ↔ XMR today, go to [EigenWallet](/wallets/eigenwallet). This page is for understanding where the technology came from.

What it is. COMIT (Cryptographically-secure Off-chain Multi-asset Instant Transactions) is an open protocol designed at `comit.network` for trustless cross-blockchain swaps. The protocol's signature properties — *pure* (no extra chain, no extra token), *native* (uses each blockchain's own scripting primitives), *trustless* (no third-party arbiter), *accountless* (no signup, no deposit) — informed several concrete implementations: BTC ↔ Ethereum / ERC20 (early COMIT focus), BTC ↔ Lightning, BTC ↔ Grin, and the one that mattered most for the Monero ecosystem: BTC ↔ Monero via `comit-network/xmr-btc-swap`.

Background. COMIT was incubated around 2018-2020 as a research-grade protocol effort with associated reference implementations. xmr-btc-swap (Rust) was the BTC-XMR implementation — the first production-grade trustless swap between Bitcoin and Monero. After a CCS-funded maturity push and several production releases, the COMIT team shifted focus to other projects and stopped actively maintaining the BTC ↔ XMR repo (`github.com/comit-network/xmr-btc-swap` carries an `unmaintained` notice today, with an explicit pointer to `eigenwallet/core`).

The baton was picked up by community maintainers (binarybaron and others), who forked the codebase as UnstoppableSwap, added a Tauri GUI on top of the CLI, broadened the ASB (Atomic Swap Backend) maker tooling, and shipped continuously through 2024-2025. In 2025 the project rebranded to EigenWallet while keeping the same codebase, Matrix room, and maker community intact. Today the active end-user product is eigenwallet.org; the COMIT protocol page (`comit.network`) is the research / spec / history reference.

What you trust.

• Open protocol specs. The COMIT protocol primitives (HTLCs, Scriptless Scripts) are published, peer-reviewed, and free to implement. The trustlessness is mathematical — no party can cheat without breaking discrete-log assumptions.
• Open-source reference implementation. `comit-network/xmr-btc-swap` is GPL'd and forkable. The fork lineage (UnstoppableSwap → EigenWallet) keeps the same license.
• Battle-tested. The protocol has settled tens of thousands of BTC ↔ XMR swaps over ~3+ years across implementations. No protocol-level vulnerability has resulted in a loss for users who waited out the refund timelocks.
• Curator note: no operator on the data path. This is true at the protocol layer. At the implementation layer, you trust the binary you run and the maker you pair with — see EigenWallet's entry for the implementation-specific incident history (including the active 2026-05 maker-side advisory).

Operational specs.

• Active end-user product: [EigenWallet](/wallets/eigenwallet) — desktop GUI + ASB CLI, Linux / macOS / Windows. SEPA on-ramp for EU users.
• Original reference repo: `github.com/comit-network/xmr-btc-swap` — marked unmaintained, points at EigenWallet as the maintained successor.
• Other COMIT-protocol implementations (historical): BTC ↔ ETH/ERC20, BTC ↔ Lightning, BTC ↔ Grin. None of these are currently active end-user products under the COMIT brand; their codebases remain on the COMIT GitHub for research reference.
• Protocol home: [comit.network](https://comit.network) — Matrix room + mailing list + blog. Specs, building blocks ("Native", "Instant", "Privacy-Preserving Atomic Swaps"), and historical research output.
• Pricing. Protocol page — no fees at this layer. End-user swap pricing is set per-maker on the implementation side.

Operator philosophy. COMIT's stated framing — *"Connecting all the blockchains without adding yet another one"* — was a counter-position to the early-stage "swap chain" approach (Cosmos, Polkadot, ThorChain, every wrapped-asset bridge). COMIT's bet was that trustless cross-chain settlement should be done on each chain's own primitives, not on a third blockchain that introduces new trust assumptions. That bet aged well for the Bitcoin ↔ Monero pair, where the resulting protocol delivered a working trustless swap years before any bridged-token approach could honestly claim the same property for XMR.

Grade rationale. Listed at Grade B as a protocol/lineage page — the underlying cryptography is sound and the lineage is documented, but COMIT itself no longer ships an end-user product for the BTC ↔ XMR pair. Users looking for an A-grade end-user wallet should use [EigenWallet](/wallets/eigenwallet). If you're a researcher or an integrator building on the COMIT primitives directly, the protocol home and the original `xmr-btc-swap` codebase remain useful references.

Useful when:

• You want to understand where EigenWallet's trustless swap mechanism comes from before trusting it with funds.
• You're a protocol researcher studying production-grade atomic-swap implementations between heterogeneous chains.
• You're building a new cross-chain implementation and want a peer-reviewed primitive (HTLC + Scriptless Scripts) as a starting point rather than rolling your own.
• You're writing about the history of Bitcoin ↔ Monero atomic swaps and need authoritative source links for the COMIT → UnstoppableSwap → EigenWallet lineage.

Caveats:

• Not an end-user product. This page is documentation + lineage. For actually swapping BTC ↔ XMR today, see [EigenWallet](/wallets/eigenwallet).
• The original `xmr-btc-swap` repo is unmaintained. Don't run those binaries directly — they may have known bugs that EigenWallet has since patched, and the ASB protocol versioning has moved on.
• COMIT brand activity is low. The website is up, the Matrix room is reachable, but new protocol work + active development happens on the EigenWallet side now.
• Implementation-specific incidents apply. The protocol layer is sound; the implementation layer (EigenWallet's ASB) has an active 2026-05 vulnerability advisory — see the [EigenWallet incident banner](/wallets/eigenwallet).