Cowrie Research

acinq-primary-sources-2026-04-30

5 min read

ACINQ primary-source snapshot

Last reviewed: 2026-04-30 UTC

Project status snapshot

What the official materials say

1) Corporate homepage: Lightning-focused Bitcoin company

  • URL: https://acinq.co/
  • Key takeaways:
    • The homepage metadata describes ACINQ as “a Bitcoin technology company with a focus on the Lightning Network.”
    • The structured-data block identifies ACINQ as an organization rather than a single protocol or app.
    • Even though the site itself is JS-heavy, the metadata is enough to frame ACINQ as a company centered on Lightning infrastructure.

2) Phoenix website: wallet brand and end-user distribution layer

  • URL: https://phoenix.acinq.co/
  • Key takeaways:
    • The Phoenix site metadata describes Phoenix as “The Bitcoin wallet from the future.”
    • The site uses a separate Phoenix brand and support surface, which suggests ACINQ operates a first-party consumer wallet on top of its deeper infrastructure work.
    • This matters for categorization because ACINQ is not just a library maintainer or node-software shop; it also ships user-facing wallet software.

3) Eclair README: server-side Lightning implementation with API surface

  • URL: https://raw.githubusercontent.com/ACINQ/eclair/master/README.md
  • Key takeaways:
    • Eclair is described as a Scala implementation of the Lightning Network.
    • The README says it follows the Lightning Network Specifications (BOLTs).
    • It also highlights a feature-rich HTTP JSON API for application developers.
    • The install/config docs show Eclair is meant for serious node operation alongside Bitcoin Core rather than as a lightweight demo package.
    • This is one of the strongest clues that ACINQ belongs in the library as infrastructure, not just as a wallet company.

4) lightning-kmp README: mobile-optimized Lightning engine

  • URL: https://raw.githubusercontent.com/ACINQ/lightning-kmp/master/README.md
  • Key takeaways:
    • lightning-kmp is described as a Kotlin Multiplatform implementation of the Lightning Network optimized for mobile wallets.
    • The README explicitly contrasts it with Eclair, saying Eclair is optimized for servers and routing nodes while lightning-kmp is optimized for wallet send/receive scenarios.
    • The project says it runs across platforms including iOS and Android.
    • It also states that lightning-kmp is used in Phoenix.
    • This server-versus-mobile split is the clearest architectural signal in the whole ACINQ corpus.

5) bitcoin-kmp README: reusable Bitcoin protocol primitives

  • URL: https://raw.githubusercontent.com/ACINQ/bitcoin-kmp/master/README.md
  • Key takeaways:
    • bitcoin-kmp describes itself as a Kotlin Multiplatform Bitcoin library.
    • The README lists support for Bitcoin transaction creation, signatures, scripts, BIP32, BIP39, PSBT, Taproot, and related primitives.
    • It explicitly says the library is meant to provide the pieces needed to build Bitcoin applications rather than re-implement a full Bitcoin node.
    • The README also says ACINQ uses it in lightning-kmp, showing a layered internal stack.

6) Phoenix README: self-custodial Lightning wallet

  • URL: https://raw.githubusercontent.com/ACINQ/phoenix/master/README.md
  • Key takeaways:
    • Phoenix is described as a Bitcoin wallet developed by ACINQ for sending and receiving bitcoin securely over the Lightning Network.
    • The README emphasizes that Phoenix is self-custodial and that users hold the keys and recovery phrase.
    • The app is available on both Android and iOS.
    • The codebase is split into shared business logic plus separate Android and iOS frontends, with the shared layer using lightning-kmp.
    • This confirms Phoenix is both a real production wallet and a distribution layer for ACINQ’s lower-level protocol software.

7) phoenixd README: server equivalent of Phoenix

  • URL: https://raw.githubusercontent.com/ACINQ/phoenixd/master/README.md
  • Key takeaways:
    • phoenixd is explicitly described as the server equivalent of the popular Phoenix wallet for mobile.
    • It runs natively on Linux, macOS, and Windows via WSL.
    • The README links both a homepage and API docs, signaling an operator/developer product rather than just a code sample.
    • This broadens ACINQ from wallet + node software into a wallet-to-server software continuum.

8) GitHub org: the repo layout reveals the real business shape

  • URL: https://github.com/ACINQ
  • Key takeaways:
    • The org prominently surfaces Eclair, Phoenix, lightning-kmp, bitcoin-kmp, phoenixd, and Eclair plugins.
    • Public pinned repos show ACINQ maintaining both infrastructure components and user-facing software.
    • This is a good example of a company whose repo inventory is more revealing than the homepage alone.

Whitepaper / technical-doc status

  • No canonical standalone ACINQ whitepaper or litepaper surfaced in this pass.
  • The relevant source of truth is the combination of the corporate site, the Phoenix site, and the ACINQ public repositories.
  • For categorization, the most revealing documents are the Eclair, lightning-kmp, bitcoin-kmp, Phoenix, and phoenixd READMEs because they expose the intentional split between server infrastructure, mobile wallet infrastructure, reusable Bitcoin primitives, and end-user wallet distribution.

Research notes

  • Best current category for the library: Bitcoin Lightning infrastructure / self-custodial wallet stack / mobile-and-server Lightning software platform.
  • The most important insight is that ACINQ is not just Phoenix Wallet: it maintains a layered stack spanning reusable Bitcoin primitives, a mobile-optimized Lightning engine, a server-oriented Lightning implementation, and a first-party wallet.
  • The second most important insight is that the explicit Eclair-versus-lightning-kmp split reveals a thoughtful architecture optimized for different operating environments instead of one generic Lightning codebase.
  • ACINQ is a good example of a Bitcoin company whose homepage is underspecified while the GitHub organization tells the real story.

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