Phoenixd is the server equivalent of the Phoenix wallet for developers and businesses that makes it easy to send and receive Lightning payments without compromising on self-custody. It is written in Kotlin Multiplatform and runs natively on Linux, MacOS (x86 and ARM), and Windows (WSL).

Nunchuk is a Bitcoin multisig wallet with premium features such as inheritance planning, scheduled transactions, emergency lockdown, Taproot Multisig, Decoy wallets, and more. Available on Android, iOS, and desktop.

Lark is a command line application for interacting with USB hardware wallets in Bitcoin related functions. It is a Java port of HWI.

Ark is a layer-two protocol designed to scale Bitcoin transactions .

Satochip is an open-source javacard applet implementing a cryptocurrency signing device with full BIP32/BIP39 support.

GRAIN is an open-source Nostr relay implementation written in Go, aiming to provide a highly efficient and configurable Nostr relay.

Frostr is a simple t-of-n remote signing and key rotation protocol for Nostr, powered by FROST.

Validating Lightning Signer (VLS) is a library and reference implementation for a signer module to secure Lightning nodes. It separates your Lightning private keys and security rule validation from your Lightning node into a separate signing device, enhancing security by reducing the attack surface.