While there are far too many new features in the 0.6 release to list, the following are the most interesting and impactful:
- Lightweight nodes: Previous releases required a full
bitcoindnode
running alongside c-lightning, to provide access to the Bitcoin network. This
release still requires thebitcoin-cliutility to be present, but it can
now talk to remote nodes as well, including some lightweight nodes such as
spruned. This makes it possible to run a c-lightning node on
Raspberry Pis as well as other low-powered devices. - The gossip protocol has been updated to use a more lightweight bandwidth
mechanism that asks for specific information, rather than exchanging full
network views as the previous release did. This is particularly important for
low-powered and mobile devices that would otherwise spend a lot of bandwidth
and energy downloading and verifying information they already have. - API stability: The c-lightning JSON-RPC interface and supporting
libraries have been redesigned in order to minimize changes in future
releases. This API stability should make it easy for other projects to build
on top of c-lightning because we will support this version of the API for the
foreseeable future, maintaining backward compatibility, should we introduce
any changes. - Wallet and sync: c-lightning now includes a full-fledged wallet that
manages both on-chain and off-chain funds. There is no more raw transaction
handling! All funds are automatically tracked and returned to the internal
wallet as soon as possible, with no user interaction required. In addition
the blockchain tracking now maintains an internal view of the blockchain,
ending long blockchain rescans. - TOR support: c-lightning now supports connecting to nodes over the TOR
network, auto-registering as a hidden service, and accepting incoming
connections over TOR. - The payment logic has undergone a major overhaul to support automatic
retries for routing failures, randomization of route selection, and better
feedback about the current state of a payment. - And as always: performance, performance, performance.